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diff --git a/Build/source/utils/README b/Build/source/utils/README index 5576c9d455f..979efb6f700 100644 --- a/Build/source/utils/README +++ b/Build/source/utils/README @@ -6,8 +6,8 @@ Extra utilities we (optionally) compile for TeX Live. See comments in ../texk/README. asymptote 1.75 - checked 4jun09 - http://superb-east.dl.sourceforge.net/sourceforge/asymptote/asymptote-1.73.src.tgz - configure --disable-gc # if gc make check fails + http://superb-east.dl.sourceforge.net/sourceforge/asymptote/asymptote-1.75.src.tgz + configure --enable-tetex-build --disable-gc # if gc make check fails make CFLAGS="-g -DBROKEN_COMPILER" if redefinition of solvedKnot3. dialog 1.1-20080819 - checked 20mar09 diff --git a/Build/source/utils/asymptote/doc/FAQ/asy-faq.info b/Build/source/utils/asymptote/doc/FAQ/asy-faq.info new file mode 100644 index 00000000000..5d56d06d3c5 --- /dev/null +++ b/Build/source/utils/asymptote/doc/FAQ/asy-faq.info @@ -0,0 +1,1670 @@ +Info file: asy-faq.info, -*-Text-*- +produced by bfnnconv.pl from the Bizarre Format With No Name. + +START-INFO-DIR-ENTRY +* asymptote FAQ: (asy-faq). Asymptote Frequently Asked Questions. +END-INFO-DIR-ENTRY + + +File: $prefix.info, Node: Top, Next: Question 1.1, Up: (dir) + + ASYMPTOTE FREQUENTLY ASKED QUESTIONS + 01 Jun 2009 + +This is the list of Frequently Asked Questions about Asymptote (asy). + +Index + +* Menu: +* Section 1:: About Asymptote +* Section 2:: Questions about installation and setup +* Section 3:: Questions about paths +* Section 4:: Questions about labels +* Section 5:: Questions about arrows +* Section 6:: Questions about 2D graphs +* Section 7:: Questions about programming +* Section 8:: Questions about differences between Asymptote and + MetaPost +* Section 9:: Questions about output + +Section 1, About Asymptote +* Question 1.1:: What is Asymptote? +* Question 1.2:: How do I obtain Asymptote? +* Question 1.3:: Where can I ask questions about Asymptote? +* Question 1.4:: Why was the name Asymptote chosen? +* Question 1.5:: In the internal Asymptote source code, what does the + name camp refer to? + +Section 2, Questions about installation and setup +* Question 2.1:: Is it possible to install Asymptote on Mac OS X? +* Question 2.2:: Why do I get the error Bad CPU type in executable on + installing Asymptote from the MAC OS binary? +* Question 2.3:: What do I do if I get the error: Error: pdfetex (file + pdftex.cfg): cannot open config file...texinfo.tex + appears to be broken? +* Question 2.4:: What do I do if I get the error: ! Undefined control + sequence. l.6 @copying? +* Question 2.5:: Is it possible to integrate Asymptote into LaTeX? +* Question 2.6:: Is it possible to integrate Asymptote into latex or + pdflatex? +* Question 2.7:: Do I need the tkinter package to install an Asymptote + rpm binary? +* Question 2.8:: What does the path %USERPROFILE%\.asy\config.asy mean? +* Question 2.9:: Why do I get the error "string not terminated" when I + try to set settings.dir="C:\asymptote\";? +* Question 2.10:: How do I change environment variables in Microsoft + Windows, for example, in order to change the default + PostScript viewer? +* Question 2.11:: Under Microsoft Windows XP, why do I get an error like + "Invalid Parameter - 432x432"? +* Question 2.12:: Why does Asymptote freeze upon trying to draw a label + with my MikTex installation under Microsoft Windows? + +Section 3, Questions about paths +* Question 3.1:: Why do I get a syntax error message when I specify an + integer value for the path tension? +* Question 3.2:: Shouldn't dots always be the same size? + +Section 4, Questions about labels +* Question 4.1:: How do I get Greek letters like omega to show up in my + labels? +* Question 4.2:: Can Asymptote use matrices as labels? +* Question 4.3:: How do I tell Asymptote to load a particular LaTeX + package, like mathptmx? +* Question 4.4:: How can I use international fonts in Asymptote labels? +* Question 4.5:: How can I use Fourier fonts? +* Question 4.6:: Is there any way to change the default appearance of + the decimal separator, using a comma instead of a dot? +* Question 4.7:: How can I get a rotated label with the filled box + rotated as well so that it fits the text? +* Question 4.8:: How can I rotate labels in a 3D figure? +* Question 4.9:: How can I draw some squares and circles of a fixed + size and put a label in the middle of them? +* Question 4.10:: The binary operator * can be used to scale the color + of a pen by a real number. Does this scaling factor + have to be less than 1? +* Question 4.11:: Why is the space after the comma decimal separator in + my locale so large? +* Question 4.12:: How can I prevent + texpreamble("\usepackage[pdftex]{hyperref}") from + changing the page size? + +Section 5, Questions about arrows +* Question 5.1:: How do I draw two arrows at arbitrary positions along + a path? +* Question 5.2:: How do I reverse the direction of an arrowhead? +* Question 5.3:: How do I change the size of all arrows? +* Question 5.4:: Can I create other arrowhead styles? + +Section 6, Questions about 2D graphs +* Question 6.1:: How can I draw x axis ticks on the right side, with + the tick labels on the left side (relative to the axis + path)? +* Question 6.2:: How can I reposition the x axis label to + three-quarters along the axis length? +* Question 6.3:: How can I move the x axis label down 10bp? +* Question 6.4:: Can I use different pens for the axis, the axis label, + and the tick labels? +* Question 6.5:: How can I change the font type of the axes label? +* Question 6.6:: How can I change the font type of the tick labels on + an axis? +* Question 6.7:: How can I prevent axes tick labels from rendering on + top of each other? +* Question 6.8:: How do I make the plot region of a graph, ignoring + labels and legends, have a fixed size? +* Question 6.9:: How can I plot a function f(x) within [0,1]x[0,2] + without explicitly calculating the x values for which + f(x) hits the boundary? +* Question 6.10:: Is it possible to define customized palettes? +* Question 6.11:: Is there an easy way to graph factorial functions + nicely? +* Question 6.12:: How do I indicate that a certain length should be + exactly the size I prescribe with no rescaling, within + a picture which has its own size? +* Question 6.13:: How can I make the y axis display base-2 logarithmic + values? +* Question 6.14:: How can I align the x axes of two graphs on the same + figure? +* Question 6.15:: How can I change the direction of the y-axis, such + that negatives values are on the upper y-axis? +* Question 6.16:: How can I fill a path with a function that defines the + color of each location? +* Question 6.17:: Is there a way to draw a function that is not + explicitly given, such as (y - 2)^2 = x - 1 ? +* Question 6.18:: Is it possible to reverse or stretch an axis? +* Question 6.19:: Why can't I use the UnFill option to draw graphs with + empty markers? +* Question 6.20:: How can I force several images to use the same palette + range (e.g. the entire 0-255 grayscale range)? + +Section 7, Questions about programming +* Question 7.1:: Is Asymptote an interpreter or a compiler? +* Question 7.2:: What is the difference between a frame and a picture? +* Question 7.3:: What is the difference between a path and a guide? +* Question 7.4:: What is a convenient way to declare and initialize an + array of pictures? +* Question 7.5:: Is there a way to define functions that act on arrays + in general (i.e. work for arrays of any type)? +* Question 7.6:: Is there any way to declare structures ahead of their + definition, e.g. where struct A performs some + operation on struct B, but B contains an A member? +* Question 7.7:: Where are static variables in for loops allocated? +* Question 7.8:: Is there a debugger for asy? +* Question 7.9:: Do you accept patches for Asymptote? + +Section 8, Questions about differences between Asymptote and + MetaPost +* Question 8.1:: What is the equivalent of the MetaPost c[a,b] + interpolation operator? +* Question 8.2:: How does picture scaling differ in Asymptote and + MetaPost? +* Question 8.3:: How can I avoid automatic scaling of a picture? +* Question 8.4:: What is the equivalent of MetaPost ... command? +* Question 8.5:: What is the equivalent of the MetaPost pickup command? +* Question 8.6:: What is the equivalent of the MetaPost whatever + command? +* Question 8.7:: What is the equivalent for the MetaPost command for + lray - horiz*v - verti*u = whatever*(LightSource - R), + a system of three linear equations for three unknowns: + horiz, verti, whatever? +* Question 8.8:: In MetaPost, it is possible to have a drawing remain + the same size in different pictures by defining a unit + u and explicitly multiply all the coordinates by u. Is + there a better way to do this in Asymptote? +* Question 8.9:: In MetaPost, one could produce tiling pictures by + generating a picture, and then clipping the picture to + a rectangle of fixed dimensions around the center of + the picture. How is that done in Asymptote? + +Section 9, Questions about output +* Question 9.1:: How can I disable automatic invocation of the PS + viewer after an asy file is done processing? +* Question 9.2:: How do I output jpeg images? +* Question 9.3:: Can I embed bitmaps (photos) into my drawings and + position and scale them? +* Question 9.4:: Does Asymptote support direct PDF output? +* Question 9.5:: How to I produce large pictures of high quality in + raster format (e.g. png, giff etc). +* Question 9.6:: Is it possible to produce multi-page documents with + asymptote? + + + +File: asy-faq.info, Node: Section 1, Next: Section 2, Previous: Top, Up: Top + +About Asymptote + +* Menu: +* Question 1.1:: What is Asymptote? +* Question 1.2:: How do I obtain Asymptote? +* Question 1.3:: Where can I ask questions about Asymptote? +* Question 1.4:: Why was the name Asymptote chosen? +* Question 1.5:: In the internal Asymptote source code, what does the + name camp refer to? + + + +File: asy-faq.info, Node: Question 1.1, Next: Question 1.2, Previous: Top, Up: Section 1 + +Question 1.1. What is Asymptote? + +Asymptote is a vector graphics language designed for technical graphics, +inspired by MetaPost but with IEEE floating-point numerics, native +three-dimensional graphics, Grayscale/RGB/CMYK colourspaces, and a +C++-like syntax. Unlike MetaPost, it natively supports multiple-segment +paths (and hence regions other than simply connected ones), tiling +patterns, Gouraud shading, tensor patch shading, and PostScript images. + + +File: asy-faq.info, Node: Question 1.2, Next: Question 1.3, Previous: Question 1.1, Up: Section 1 + +Question 1.2. How do I obtain Asymptote? + +Binary releases are available for Linux, MacOS X, and Microsoft Windows +platforms, in addition to full source code, from the website +http://asymptote.sourceforge.net/. Many Linux distributions (such as +RedHat and Debian) now include an Asymptote package (check your +distribution's documentation for further information about this). + + +File: asy-faq.info, Node: Question 1.3, Next: Question 1.4, Previous: Question 1.2, Up: Section 1 + +Question 1.3. Where can I ask questions about Asymptote? + +If you have a question, please try to find an answer in this FAQ, in the +extensive Asymptote documentation at +http://asymptote.sourceforge.net/doc/, or search the forum: +http://sourceforge.net/forum/forum.php?forum_id=409349. + + +File: asy-faq.info, Node: Question 1.4, Next: Question 1.5, Previous: Question 1.3, Up: Section 1 + +Question 1.4. Why was the name Asymptote chosen? + +Well, it isn't the perfect graphics package, but we do think it is getting +there asymptotically... + + +File: asy-faq.info, Node: Question 1.5, Next: Question 2.1, Previous: Question 1.4, Up: Section 1 + +Question 1.5. In the internal Asymptote source code, what does the name camp refer to? + +That was our original tentative name for this project, which stood for +"C's Answer to MetaPost" (the language that inspired Asymptote). However, +we eventually decided that the name Asymptote better emphasizes the +mathematical and graphical nature of this language. + + +File: asy-faq.info, Node: Section 2, Next: Section 3, Previous: Section 1, Up: Top + +Questions about installation and setup + +* Menu: +* Question 2.1:: Is it possible to install Asymptote on Mac OS X? +* Question 2.2:: Why do I get the error Bad CPU type in executable on + installing Asymptote from the MAC OS binary? +* Question 2.3:: What do I do if I get the error: Error: pdfetex (file + pdftex.cfg): cannot open config file...texinfo.tex + appears to be broken? +* Question 2.4:: What do I do if I get the error: ! Undefined control + sequence. l.6 @copying? +* Question 2.5:: Is it possible to integrate Asymptote into LaTeX? +* Question 2.6:: Is it possible to integrate Asymptote into latex or + pdflatex? +* Question 2.7:: Do I need the tkinter package to install an Asymptote + rpm binary? +* Question 2.8:: What does the path %USERPROFILE%\.asy\config.asy mean? +* Question 2.9:: Why do I get the error "string not terminated" when I + try to set settings.dir="C:\asymptote\";? +* Question 2.10:: How do I change environment variables in Microsoft + Windows, for example, in order to change the default + PostScript viewer? +* Question 2.11:: Under Microsoft Windows XP, why do I get an error like + "Invalid Parameter - 432x432"? +* Question 2.12:: Why does Asymptote freeze upon trying to draw a label + with my MikTex installation under Microsoft Windows? + + + +File: asy-faq.info, Node: Question 2.1, Next: Question 2.2, Previous: Question 1.5, Up: Section 2 + +Question 2.1. Is it possible to install Asymptote on Mac OS X? + +It is easy to compile Asymptote directly from the source code at +http://sourceforge.net/project/showfiles.php?group_id=120000 We recommend +first upgrading to the latest GNU readline library, unless you don't care +about interactive readline support (in which case configure will +automatically detect and disable obsolete versions of the readline +library). Marius Schamschula also maintains a binary package for various +MacOS X platforms +http://www.hmug.org/pub/MacOS_X/X/Applications/Publishing/asymptote. + + +File: asy-faq.info, Node: Question 2.2, Next: Question 2.3, Previous: Question 2.1, Up: Section 2 + +Question 2.2. Why do I get the error Bad CPU type in executable on installing Asymptote from the MAC OS binary? + +This means either that you have a binary distribution for another MAC +architecture, or (according to Marius Schamschula) that you may have a +missing library. The simplest solution is to compile Asymptote directly +from the official source: +http://sourceforge.net/project/showfiles.php?group_id=120000. + + +File: asy-faq.info, Node: Question 2.3, Next: Question 2.4, Previous: Question 2.2, Up: Section 2 + +Question 2.3. What do I do if I get the error: Error: pdfetex (file pdftex.cfg): cannot open config file...texinfo.tex appears to be broken? + +Simply put http://asymptote.sourceforge.net/asymptote.pdf in the directory +doc and repeat the command make all. Or, if you don't want to build a +local copy of the documentation, simply proceed with make install-asy. + + +File: asy-faq.info, Node: Question 2.4, Next: Question 2.5, Previous: Question 2.3, Up: Section 2 + +Question 2.4. What do I do if I get the error: ! Undefined control sequence. l.6 @copying? + +Either upgrade your texinfo package or follow one of the easy work arounds +in *Note Question 2.3:: `What do I do if I get the error: Error: pdfetex +(file pdftex.cfg): cannot open config file...texinfo.tex appears to be +broken?'. + + +File: asy-faq.info, Node: Question 2.5, Next: Question 2.6, Previous: Question 2.4, Up: Section 2 + +Question 2.5. Is it possible to integrate Asymptote into LaTeX? + +Yes, see the example latexusage.tex. Dario Teixeira has also written a +detailed guide on the topic. You can download it from +http://dario.dse.nl/projects/asylatex/. + +Philippe Ivaldi has contributed an Asymptote mode for Emacs users +http://asymptote.sourceforge.net/doc/Editing-modes.html, which includes a +lasy-mode that allows one to compile and view the output of one +\begin{asy}...\end{asy} section at a time. + + +File: asy-faq.info, Node: Question 2.6, Next: Question 2.7, Previous: Question 2.5, Up: Section 2 + +Question 2.6. Is it possible to integrate Asymptote into latex or pdflatex? + +Yes, as of version 1.14, Asymptote supports latex and pdflatex (both in +EPS/PDF and inline mode), as illustrated by the example latexusage.tex: + +pdflatex latexusage +asy latexusage +pdflatex latexusage + +File: asy-faq.info, Node: Question 2.7, Next: Question 2.8, Previous: Question 2.6, Up: Section 2 + +Question 2.7. Do I need the tkinter package to install an Asymptote rpm binary? + +No, you don't need tkinter unless you want to try out the GUI xasy. Try + +rpm -Uvh --nodeps asymptote-x.xx-1.i386.rpm +where x.xx represents the version number. + + +File: asy-faq.info, Node: Question 2.8, Next: Question 2.9, Previous: Question 2.7, Up: Section 2 + +Question 2.8. What does the path %USERPROFILE%\.asy\config.asy mean? + +That is the way that Microsoft Windows refers to the user profile +directory. There's nothing really to understand here, just put your +configuration commands in the file config.asy in a new folder +%USERPROFILE%\.asy. + + +File: asy-faq.info, Node: Question 2.9, Next: Question 2.10, Previous: Question 2.8, Up: Section 2 + +Question 2.9. Why do I get the error "string not terminated" when I try to set settings.dir="C:\asymptote\";? + +The backslash is an escape character here, so \" is interpreted as a +verbatim quotation mark, leaving the string without a terminating +quotation mark. Fortunately, this is the only escaped character in +double-quoted strings. A final backslash isn't needed here anyway, but +should you really want one somewhere, you can say: +settings.dir="C:\asymptote"+'\\';. + + +File: asy-faq.info, Node: Question 2.10, Next: Question 2.11, Previous: Question 2.9, Up: Section 2 + +Question 2.10. How do I change environment variables in Microsoft Windows, for example, in order to change the default PostScript viewer? + +While it is easier to set the corresponding Asymptote configuration +variable in your config.asy file, here is the procedure for changing +Microsoft Windows environment variables: + +Click on the [Start] button + +* RIGHT-click on 'My Computer' + +* Choose 'Properties' from the popup menu + +* Click the 'Advanced' tab + +* Click the 'Environment Variables' button. + + +File: asy-faq.info, Node: Question 2.11, Next: Question 2.12, Previous: Question 2.10, Up: Section 2 + +Question 2.11. Under Microsoft Windows XP, why do I get an error like "Invalid Parameter - 432x432"? + +This means that ImageMagick wasn't properly installed and you are using +the MSDOS convert program rather than the ImageMagick one. Or you may have +installed ImageMagick but ran Asymptote from an existing MSDOS window. In +that case, simply open a new window and try again. If that doesn't work, +check that + +convert --version +returns something like + +Version: ImageMagick 6.2.8 06/27/06 Q16 http://www.imagemagick.org + +File: asy-faq.info, Node: Question 2.12, Next: Question 3.1, Previous: Question 2.11, Up: Section 2 + +Question 2.12. Why does Asymptote freeze upon trying to draw a label with my MikTex installation under Microsoft Windows? + +Likely, this means that latex and dvips are not in your default path. Try +adding the appropriate paths in your config.asy file, for example: + +import settings; +latex="C:\Program Files\MiKTeX 2.7\miktex\bin\latex.exe"; +dvips="C:\Program Files\MiKTeX 2.7\miktex\bin\dvips.exe"; + +File: asy-faq.info, Node: Section 3, Next: Section 4, Previous: Section 2, Up: Top + +Questions about paths + +* Menu: +* Question 3.1:: Why do I get a syntax error message when I specify an + integer value for the path tension? +* Question 3.2:: Shouldn't dots always be the same size? + + + +File: asy-faq.info, Node: Question 3.1, Next: Question 3.2, Previous: Question 2.12, Up: Section 3 + +Question 3.1. Why do I get a syntax error message when I specify an integer value for the path tension? + +What is happening here is that + +draw((0,0)..tension 2..(0,50)..(100,100)); +is read as + +draw((0,0)..tension 2. .(0,50)..(100,100)); +So the first . after the two is treated as a decimal point. Just put a +space after the integer tension value: + +draw((0,0)..tension 2 ..(0,50)..(100,100)); + +File: asy-faq.info, Node: Question 3.2, Next: Question 4.1, Previous: Question 3.1, Up: Section 3 + +Question 3.2. Shouldn't dots always be the same size? + +From the documentation: + +"The dot command defined in the module plain draws a dot having a diameter +equal to an explicit pen linewidth or the default linewidth magnified by +dotfactor (6 by default)." + +Thus, when you use the default pen, the dot will have size 6*linewidth, +but when you give a pen with an explicit width specified, you will have a +dot of size linewidth. If you want the first case to behave like the +second, you may set dotfactor=1. + + +File: asy-faq.info, Node: Section 4, Next: Section 5, Previous: Section 3, Up: Top + +Questions about labels + +* Menu: +* Question 4.1:: How do I get Greek letters like omega to show up in my + labels? +* Question 4.2:: Can Asymptote use matrices as labels? +* Question 4.3:: How do I tell Asymptote to load a particular LaTeX + package, like mathptmx? +* Question 4.4:: How can I use international fonts in Asymptote labels? +* Question 4.5:: How can I use Fourier fonts? +* Question 4.6:: Is there any way to change the default appearance of + the decimal separator, using a comma instead of a dot? +* Question 4.7:: How can I get a rotated label with the filled box + rotated as well so that it fits the text? +* Question 4.8:: How can I rotate labels in a 3D figure? +* Question 4.9:: How can I draw some squares and circles of a fixed + size and put a label in the middle of them? +* Question 4.10:: The binary operator * can be used to scale the color + of a pen by a real number. Does this scaling factor + have to be less than 1? +* Question 4.11:: Why is the space after the comma decimal separator in + my locale so large? +* Question 4.12:: How can I prevent + texpreamble("\usepackage[pdftex]{hyperref}") from + changing the page size? + + + +File: asy-faq.info, Node: Question 4.1, Next: Question 4.2, Previous: Question 3.2, Up: Section 4 + +Question 4.1. How do I get Greek letters like omega to show up in my labels? + +In (La)TeX, Greek letters can be obtained in math mode by prepending a +backslash to the letter name. So for a omega symbol, use "$\omega$". +Everything between the dollar signs is considered to be a math formula. +Uppercase Greek letters can be used by capitalizing the first letter of +the name: + +label("$\omega$",(0,0)); +label("$\Omega$",(20,0)); + +File: asy-faq.info, Node: Question 4.2, Next: Question 4.3, Previous: Question 4.1, Up: Section 4 + +Question 4.2. Can Asymptote use matrices as labels? + +Yes: +usepackage("amsmath"); +label("$\begin{matrix} 1 & 2 \\\ 1 & 1 \end{matrix}$",(0,0)); + +File: asy-faq.info, Node: Question 4.3, Next: Question 4.4, Previous: Question 4.2, Up: Section 4 + +Question 4.3. How do I tell Asymptote to load a particular LaTeX package, like mathptmx? + +Put + +usepackage("mathptmx"); +at the beginning of your file. Note: to enable the Adobe Times Roman font +for text, you will also need to say: +defaultpen(TimesRoman()); + +File: asy-faq.info, Node: Question 4.4, Next: Question 4.5, Previous: Question 4.3, Up: Section 4 + +Question 4.4. How can I use international fonts in Asymptote labels? + +See http://asymptote.sourceforge.net/doc/unicode.html. + + +File: asy-faq.info, Node: Question 4.5, Next: Question 4.6, Previous: Question 4.4, Up: Section 4 + +Question 4.5. How can I use Fourier fonts? + +usepackage("fourier"); +defaultpen(font("T1","fut\textfamilyextension","m","n")); + +File: asy-faq.info, Node: Question 4.6, Next: Question 4.7, Previous: Question 4.5, Up: Section 4 + +Question 4.6. Is there any way to change the default appearance of the decimal separator, using a comma instead of a dot? + +Just set your locale appropriately: + +locale("it_IT"); +usepackage("icomma"); +label(format(0.5)); + +File: asy-faq.info, Node: Question 4.7, Next: Question 4.8, Previous: Question 4.6, Up: Section 4 + +Question 4.7. How can I get a rotated label with the filled box rotated as well so that it fits the text? + +frame f; +label(f,"This is some text",white,Fill(blue)); +add(rotate(65)*f); + +File: asy-faq.info, Node: Question 4.8, Next: Question 4.9, Previous: Question 4.7, Up: Section 4 + +Question 4.8. How can I rotate labels in a 3D figure? + +You need to first project the triple to a pair like this: + +import three; +size(100,100); + +draw(rotate(90,project(Z))*"A",O--X); + +File: asy-faq.info, Node: Question 4.9, Next: Question 4.10, Previous: Question 4.8, Up: Section 4 + +Question 4.9. How can I draw some squares and circles of a fixed size and put a label in the middle of them? + +Fixed-size objects should be drawn on a separate picture and then added to +currentpicture. Here is one way (see also +http://asymptote.sourceforge.net/gallery/subpictures.asy and +http://asymptote.sourceforge.net/gallery/mosquito.asy): + +real u=2cm; + +picture square; +draw(square,scale(u)*shift(-0.5,-0.5)*unitsquare); + +picture circle; +draw(circle,scale(0.5u)*unitcircle); + +void add(picture pic=currentpicture, Label L, picture object, pair z) { +add(pic,object,z); +label(pic,L,z); +} + +add("square",square,(0,0)); +add("circle",circle,(5cm,0)); + +File: asy-faq.info, Node: Question 4.10, Next: Question 4.11, Previous: Question 4.9, Up: Section 4 + +Question 4.10. The binary operator * can be used to scale the color of a pen by a real number. Does this scaling factor have to be less than 1? + +The scaling factor can be greater than 1. But keep in mind that the rgb +color components saturate at 1. + +Try +write(cyan); write(0.8*cyan); write(1.5*cyan); +and you will quickly see what is going on. + +To get a lighter cyan you can say white+cyan, which yields rgb(0.5,1,1). +If you want something even lighter specify the rgb colors directly, for +example, rgb(0.9,1,1). + +Alternatively, work in cmyk colour space, which is nicer in that it +handles saturation separately from hue: + +0.1*Cyan is light and 0.9*Cyan is dark. You can also say 0.1*cmyk(red). + + +File: asy-faq.info, Node: Question 4.11, Next: Question 4.12, Previous: Question 4.10, Up: Section 4 + +Question 4.11. Why is the space after the comma decimal separator in my locale so large? + +LaTeX is treating the comma as punctuation and not as a decimal separator. +The solution is to load the icomma package near the beginning of your +file: +usepackage("icomma"); + +File: asy-faq.info, Node: Question 4.12, Next: Question 5.1, Previous: Question 4.11, Up: Section 4 + +Question 4.12. How can I prevent texpreamble("\usepackage[pdftex]{hyperref}") from changing the page size? + +texpreamble("\usepackage[pdftex,setpagesize=false]{hyperref}"); + +File: asy-faq.info, Node: Section 5, Next: Section 6, Previous: Section 4, Up: Top + +Questions about arrows + +* Menu: +* Question 5.1:: How do I draw two arrows at arbitrary positions along + a path? +* Question 5.2:: How do I reverse the direction of an arrowhead? +* Question 5.3:: How do I change the size of all arrows? +* Question 5.4:: Can I create other arrowhead styles? + + + +File: asy-faq.info, Node: Question 5.1, Next: Question 5.2, Previous: Question 4.12, Up: Section 5 + +Question 5.1. How do I draw two arrows at arbitrary positions along a path? + +Assuming that at least one of the arrowheads is to be filled, you can do +this: + +size(200); +path g = (0,0)..(1,3)..(3,0); +draw(g,Arrow(Relative(0.9))); +add(arrow(g,invisible,FillDraw(black),Relative(0.5))); +add(arrow(reverse(g),invisible,FillDraw(white,black),Relative(0.9))); +If both of the arrowheads are to be drawn with filltype NoFill, one will +need to create a specialized version of the arrow routine in +plain_arrows.asy: + +void arrow(frame f, arrowhead arrowhead=DefaultHead, + path g, pen p=currentpen, real size=0, + real angle=arrowangle, filltype filltype=arrowhead.defaultfilltype, + position position=EndPoint, bool forwards=true, + margin margin=NoMargin, bool center=false); + +File: asy-faq.info, Node: Question 5.2, Next: Question 5.3, Previous: Question 5.1, Up: Section 5 + +Question 5.2. How do I reverse the direction of an arrowhead? + +Simply reverse the direction of the path. + +path g=((0,0)--(5cm,0)); +draw(reverse(g),Arrow(Relative(0.55))); + +File: asy-faq.info, Node: Question 5.3, Next: Question 5.4, Previous: Question 5.2, Up: Section 5 + +Question 5.3. How do I change the size of all arrows? + +To override the arrowsize you can give every Arrow drawing attribute a +real size argument. If you want to do this globally, you can override the +pen-dependent arrowsize function like this: + +arrowsize=new real(pen p=currentpen) {return 2mm;}; + +File: asy-faq.info, Node: Question 5.4, Next: Question 6.1, Previous: Question 5.3, Up: Section 5 + +Question 5.4. Can I create other arrowhead styles? + +Yes, you can build custom arrowheads like this (see the predefined +arrowhead styles in plain_arrows.asy for further examples): + +arrowhead DotHead; +DotHead.head=new path(path g, position position=EndPoint, pen p=currentpen, + real size=0, real angle=arrowangle) { + if(size == 0) size=DotHead.size(p); + bool relative=position.relative; + real position=position.position.x; + if(relative) position=reltime(g,position); + path r=subpath(g,position,0); + pair x=point(r,0); + real t=arctime(r,size); + pair y=point(r,t); + return circle(0.5(x+y),0.5size); +}; + +size(100); +draw((0,0)..(1,1)..(2,0),Arrow(DotHead)); +dot((2,0),red); +If you submit your alternate arrowheads to the Forum or the Patch +Tracking System, we'll consider including them in a future release. + + +File: asy-faq.info, Node: Section 6, Next: Section 7, Previous: Section 5, Up: Top + +Questions about 2D graphs + +* Menu: +* Question 6.1:: How can I draw x axis ticks on the right side, with + the tick labels on the left side (relative to the axis + path)? +* Question 6.2:: How can I reposition the x axis label to + three-quarters along the axis length? +* Question 6.3:: How can I move the x axis label down 10bp? +* Question 6.4:: Can I use different pens for the axis, the axis label, + and the tick labels? +* Question 6.5:: How can I change the font type of the axes label? +* Question 6.6:: How can I change the font type of the tick labels on + an axis? +* Question 6.7:: How can I prevent axes tick labels from rendering on + top of each other? +* Question 6.8:: How do I make the plot region of a graph, ignoring + labels and legends, have a fixed size? +* Question 6.9:: How can I plot a function f(x) within [0,1]x[0,2] + without explicitly calculating the x values for which + f(x) hits the boundary? +* Question 6.10:: Is it possible to define customized palettes? +* Question 6.11:: Is there an easy way to graph factorial functions + nicely? +* Question 6.12:: How do I indicate that a certain length should be + exactly the size I prescribe with no rescaling, within + a picture which has its own size? +* Question 6.13:: How can I make the y axis display base-2 logarithmic + values? +* Question 6.14:: How can I align the x axes of two graphs on the same + figure? +* Question 6.15:: How can I change the direction of the y-axis, such + that negatives values are on the upper y-axis? +* Question 6.16:: How can I fill a path with a function that defines the + color of each location? +* Question 6.17:: Is there a way to draw a function that is not + explicitly given, such as (y - 2)^2 = x - 1 ? +* Question 6.18:: Is it possible to reverse or stretch an axis? +* Question 6.19:: Why can't I use the UnFill option to draw graphs with + empty markers? +* Question 6.20:: How can I force several images to use the same palette + range (e.g. the entire 0-255 grayscale range)? + + + +File: asy-faq.info, Node: Question 6.1, Next: Question 6.2, Previous: Question 5.4, Up: Section 6 + +Question 6.1. How can I draw x axis ticks on the right side, with the tick labels on the left side (relative to the axis path)? + +import graph; + +size(250,200,IgnoreAspect); + +draw(graph(exp,-1,1),red); + +xaxis("$x$",RightTicks(Label(align=left))); +yaxis("$y$",RightTicks); + +File: asy-faq.info, Node: Question 6.2, Next: Question 6.3, Previous: Question 6.1, Up: Section 6 + +Question 6.2. How can I reposition the x axis label to three-quarters along the axis length? + +import graph; + +size(250,200,IgnoreAspect); + +draw(graph(exp,-1,1),red); + +xaxis(Label("$x$",0.75),LeftTicks); +yaxis("$y$",RightTicks); + +File: asy-faq.info, Node: Question 6.3, Next: Question 6.4, Previous: Question 6.2, Up: Section 6 + +Question 6.3. How can I move the x axis label down 10bp? + +import graph; +size(250,200,IgnoreAspect); + +draw(graph(exp,-1,1),red); + +xaxis(shift(0,-10)*"$x$",LeftTicks); +yaxis("$y$",RightTicks); + +File: asy-faq.info, Node: Question 6.4, Next: Question 6.5, Previous: Question 6.3, Up: Section 6 + +Question 6.4. Can I use different pens for the axis, the axis label, and the tick labels? + +Yes: + +import graph; +size(300,200,IgnoreAspect); + +xlimits(-50,50); +ylimits(0,100); + +xaxis(Label("$x$",MidPoint,red),Bottom,blue,LeftTicks(green)); +yaxis("$y$",Left,RightTicks); + +File: asy-faq.info, Node: Question 6.5, Next: Question 6.6, Previous: Question 6.4, Up: Section 6 + +Question 6.5. How can I change the font type of the axes label? + +import graph; +size(300,200,IgnoreAspect); + +xlimits(-50,50); +ylimits(0,100); + +xaxis("x",Bottom,Courier("m","n"),LeftTicks); +yaxis("$y$",Left,RightTicks); + +File: asy-faq.info, Node: Question 6.6, Next: Question 6.7, Previous: Question 6.5, Up: Section 6 + +Question 6.6. How can I change the font type of the tick labels on an axis? + +Tick labels are by default typeset in (TeX) math mode, so to use other +fonts you need to override the default tick format: + +import graph; +size(300,200,IgnoreAspect); + +xlimits(-50,50); +ylimits(0,100); + +xaxis("$x$",Bottom,LeftTicks("%.4g",Courier("m","n")+fontsize(12))); +yaxis("$y$",Left,RightTicks); + +File: asy-faq.info, Node: Question 6.7, Next: Question 6.8, Previous: Question 6.6, Up: Section 6 + +Question 6.7. How can I prevent axes tick labels from rendering on top of each other? + +Either: + +(i) give LeftTicks/RightTicks/Ticks the arguments beginlabel=false and/or +endlabel=false; + +(ii) explicitly remove specific ticks and their labels (drawing them +manually; see +http://asymptote.svn.sourceforge.net/viewvc/asymptote/trunk/asymptote/base/graph.asy +for the definition of NoZero): + +import graph; + +size(10cm); + +real f(real x) {return x^2;} + +draw(graph(f,-2,2)); + +xaxis(Ticks(NoZero)); +yaxis(Ticks(NoZero)); + +label("$0$",(0,0),SW); +(iii) explicitly remove specific tick labels and draw them manually (see +http://asymptote.svn.sourceforge.net/viewvc/asymptote/trunk/asymptote/base/graph.asy +for the definition of NoZeroFormat): + +import graph; + +size(10cm); + +real f(real x) {return x^2;} + +draw(graph(f,-2,2)); + +xaxis(Ticks(NoZeroFormat)); +yaxis(Ticks(NoZeroFormat)); + +label("$0$",(0,0),SW); +(iv) use the xasy GUI to move overlapping labels; + +(v) change the Label argument of LeftTicks, RightTicks, or Ticks to: + +Label(currentpen+overwrite(Move)) +Solution (v) will move labels that might otherwise overwrite a previous +label. Other possible overwrite arguments are Allow (allows overlapping +labels; the default), Suppress (an overlapping label will not be written +at all), SuppressQuiet, and MoveQuiet. The last two achieve the same +result as the non-quiet types, but will not notify you which labels are +overlapping. See: http://asymptote.sourceforge.net/doc/Pens.html. + +In the case of a user-specified tick array, you can change which labels +get suppressed/moved by changing the order of array entries. + + +File: asy-faq.info, Node: Question 6.8, Next: Question 6.9, Previous: Question 6.7, Up: Section 6 + +Question 6.8. How do I make the plot region of a graph, ignoring labels and legends, have a fixed size? + +Either: + +i) Specify an explicit unitsize, which overrides any call to size: +unitsize(x=1cm,y=2cm); +ii) Explicitly tell Asymptote to map the plot region to a specific size: +import graph; +real[] x={0,1,2,3}; +real[] y=x^2; +draw(graph(x,y),red); +xaxis("$x$",BottomTop,LeftTicks); +yaxis("$y$",LeftRight,RightTicks); + +size(5cm,5cm,point(SW),point(NE)); + +label("$f_\mathrm{T}$",point(N),2N); +iii) Specify the points in user coordinates that should correspond to a +given picture size: + +import graph; + +size(250,200,IgnoreAspect); + +draw(graph(exp,-1,1),red); + +xaxis("$x$",BottomTop,LeftTicks); +yaxis("$y$",LeftRight,RightTicks); + +fixedscaling((-1.5,-0.5),(1.5,3.5)); +In this example, the user coordinate (-1.5,-0.5) will end up being the +lower left corner of the figure and (1.5,3.5) will be the upper right +corner. You can use this option to ensure multiple figures have the same +scaling and same resulting figure size (just ensure the two coordinates +given to fixedscaling() leaves room for any labels). + +See also http://asymptote.sourceforge.net/doc/Frames-and-pictures.html. + + +File: asy-faq.info, Node: Question 6.9, Next: Question 6.10, Previous: Question 6.8, Up: Section 6 + +Question 6.9. How can I plot a function f(x) within [0,1]x[0,2] without explicitly calculating the x values for which f(x) hits the boundary? + +Call limits with the Crop option before drawing the graph: +import graph; + +size(250,200,IgnoreAspect); + +draw(graph(exp,-1,1),red); + +limits((0,0),(1,2),Crop); + +xaxis("$x$",BottomTop,LeftTicks); +yaxis("$y$",LeftRight,RightTicks); +See also http://asymptote.sourceforge.net/doc/graph.html. + + +File: asy-faq.info, Node: Question 6.10, Next: Question 6.11, Previous: Question 6.9, Up: Section 6 + +Question 6.10. Is it possible to define customized palettes? + +Yes, you may generate your own pen[] array. For example: + +int NColors=32768; +pen[] MyPalette=new pen[NColors]; +real step=1/(NColors-1.0); +// Start at black: rgb(0,0,0) +// End at yellow: rgb(1,1,0) +for(int i=0; i < NColors; ++i) { + real rgval=i*step; + MyPalette[i]=rgb(rgval,rgval,0.0); +} + +File: asy-faq.info, Node: Question 6.11, Next: Question 6.12, Previous: Question 6.10, Up: Section 6 + +Question 6.11. Is there an easy way to graph factorial functions nicely? + +The example below shows a continuous function and two methods for placing +markers at integer values of x: + +import graph; + +size(200,200,IgnoreAspect); + +real factorial(real t) {return gamma(t+1);} + +scale(Linear,Log); + +// Graph the factorial function. +draw(graph(factorial,0,10)); + +// Method 1: Draw nodes, but hide line +pair F(int t) {return (t,factorial(t));} +// Graph of factorial function from 0 to 10 +pair[] z=sequence(F,11); +draw(graph(z),invisible,marker(scale(0.8mm)*unitcircle,blue,Fill)); + +// Method 2: Nongraphing routines require explicit scaling: +pair dotloc(int t) {return Scale(F(t));} +pair[] dotlocs=sequence(dotloc,11); +dot(dotlocs); + +xaxis("$x$",BottomTop,LeftTicks); +yaxis("$y$",LeftRight,RightTicks); + +File: asy-faq.info, Node: Question 6.12, Next: Question 6.13, Previous: Question 6.11, Up: Section 6 + +Question 6.12. How do I indicate that a certain length should be exactly the size I prescribe with no rescaling, within a picture which has its own size? + +Here's an easy way to do this. + +size(12cm,0); + +void distance(picture pic=currentpicture, pair A, pair B, Label L="", real n=0, + pen p=currentpen) +{ + real d=3mm; + path g=A--B; + transform T=shift(-n*d*unit(B-A)*I); + pic.add(new void(frame f, transform t) { + picture opic; + path G=T*t*g; + draw(opic,Label(L,Center,UnFill(1)),G,p,Arrows(NoFill),Bars,PenMargins); + add(f,opic.fit()); + }); + pic.addBox(min(g),max(g),T*min(p),T*max(p)); +} + +pair A=(0,0), B=(3,3); + +dot(A); +dot(B); + +distance(A,B,"$\ell$",1); + +File: asy-faq.info, Node: Question 6.13, Next: Question 6.14, Previous: Question 6.12, Up: Section 6 + +Question 6.13. How can I make the y axis display base-2 logarithmic values? + +See the example http://asymptote.sourceforge.net/gallery/2D +graphs/log2graph.asy. + + +File: asy-faq.info, Node: Question 6.14, Next: Question 6.15, Previous: Question 6.13, Up: Section 6 + +Question 6.14. How can I align the x axes of two graphs on the same figure? + +An easy way to do this, if the axes to be aligned have the same scaling +and size, is illustrated in the example +http://asymptote.sourceforge.net/gallery/2D graphs/alignedaxis.asy. + +Here is a more general solution to the problem of aligning two arbitrary +axes. One fits the second picture to a frame based on the horizontal +scaling for the first picture: + +import graph; + +real width=15cm; +real aspect=0.3; + +picture pic1,pic2; + +size(pic1,width,aspect*width,IgnoreAspect); +size(pic2,width,aspect*width,IgnoreAspect); + +scale(pic1,false); +scale(pic2,false); + +real xmin1=6; +real xmax1=9; +real xmin2=8; +real xmax2=16; + +real a1=1; +real a2=0.001; + +real f1(real x) {return a1*sin(x/2*pi);} +real f2(real x) {return a2*sin(x/4*pi);} + +draw(pic1,graph(pic1,f1,xmin1,xmax1)); +draw(pic2,graph(pic2,f2,xmin2,xmax2)); + +xaxis(pic1,Bottom,LeftTicks()); +yaxis(pic1,"$f_1(x)$",Left,RightTicks); + +xaxis(pic2,"$x$",Bottom,LeftTicks(Step=4)); +yaxis(pic2,"$f_2(x)$",Left,RightTicks); + +yequals(pic1,0,Dotted); +yequals(pic2,0,Dotted); + +pair min1=point(pic1,SW); +pair max1=point(pic1,NE); + +pair min2=point(pic2,SW); +pair max2=point(pic2,NE); + +real scale=(max1.x-min1.x)/(max2.x-min2.x); +real shift=min1.x/scale-min2.x; + +transform t1=pic1.calculateTransform(); +transform t2=pic2.calculateTransform(); +transform T=xscale(scale*t1.xx)*yscale(t2.yy); + +add(pic1.fit()); +real height=truepoint(N,user=false).y-truepoint(S,user=false).y; +add(shift(0,-height)*(shift(shift)*pic2).fit(T)); + +File: asy-faq.info, Node: Question 6.15, Next: Question 6.16, Previous: Question 6.14, Up: Section 6 + +Question 6.15. How can I change the direction of the y-axis, such that negatives values are on the upper y-axis? + +Here is a simple example (see also the example +http://asymptote.sourceforge.net/gallery/2D graphs/diatom.asy or the +discussion of Linear(-1) in the documentation): + +import graph; +size(250,200,IgnoreAspect); + +scale(Linear,Linear(-1)); + +draw(graph(log,0.1,10),red); + +xaxis("$x$",LeftTicks); +yaxis("$y$",RightTicks); + +File: asy-faq.info, Node: Question 6.16, Next: Question 6.17, Previous: Question 6.15, Up: Section 6 + +Question 6.16. How can I fill a path with a function that defines the color of each location? + +Use functionshade with a PDF tex engine, as illustrated by the example +{functionshading.asy}. + +If you want to produce PostScript output, an approximate solution for now +would be to superimpose a fine grid and specify colors to latticeshade +that depend on position as a single pen[][] lattice. Alternatively, it may +be more efficient to use tensorshade}. + + +File: asy-faq.info, Node: Question 6.17, Next: Question 6.18, Previous: Question 6.16, Up: Section 6 + +Question 6.17. Is there a way to draw a function that is not explicitly given, such as (y - 2)^2 = x - 1 ? + +Yes, use the parametric form + +y=t +x=(t-2)^2+1 +See the example http://asymptote.sourceforge.net/gallery/2D +graphs/parametricgraph.asy. + + +File: asy-faq.info, Node: Question 6.18, Next: Question 6.19, Previous: Question 6.17, Up: Section 6 + +Question 6.18. Is it possible to reverse or stretch an axis? + +The real scaling argument to Linear is used to stretch (or reverse) the +axis. To see the effect of axis stretching, be sure not to specify +IgnoreAspect in the picture size command. + +A secondary axis has the same length as the primary axis, so stretching +cannot have any effect. But one can still reverse the axis, with +Linear(-1). + + +File: asy-faq.info, Node: Question 6.19, Next: Question 6.20, Previous: Question 6.18, Up: Section 6 + +Question 6.19. Why can't I use the UnFill option to draw graphs with empty markers? + +UnFill won't work here because it only affects the local frame the markers +are initially drawn on, before being added to currentpicture. Here is a +way of achieving the desired effect (assuming a white background): + +import graph; +size(10cm,0); +pair[] z={(0,0),(0.5,0.5),(1,1)}; +path g=graph(z); + +draw(shift(0,.5)*g,marker(scale(5)*unitcircle,FillDraw(white))); + +xaxis(BottomTop,LeftTicks); +yaxis(LeftRight,RightTicks); + +File: asy-faq.info, Node: Question 6.20, Next: Question 7.1, Previous: Question 6.19, Up: Section 6 + +Question 6.20. How can I force several images to use the same palette range (e.g. the entire 0-255 grayscale range)? + +The palette color space corresponds to a range of values specified by the +argument range, which can be Full, Automatic or an explicit range +Range(pair min, pair max). Here Full} specifies a range varying from the +minimum to maximum values of the function over the sampling interval, +while Automatic selects "nice" limits. + + +File: asy-faq.info, Node: Section 7, Next: Section 8, Previous: Section 6, Up: Top + +Questions about programming + +* Menu: +* Question 7.1:: Is Asymptote an interpreter or a compiler? +* Question 7.2:: What is the difference between a frame and a picture? +* Question 7.3:: What is the difference between a path and a guide? +* Question 7.4:: What is a convenient way to declare and initialize an + array of pictures? +* Question 7.5:: Is there a way to define functions that act on arrays + in general (i.e. work for arrays of any type)? +* Question 7.6:: Is there any way to declare structures ahead of their + definition, e.g. where struct A performs some + operation on struct B, but B contains an A member? +* Question 7.7:: Where are static variables in for loops allocated? +* Question 7.8:: Is there a debugger for asy? +* Question 7.9:: Do you accept patches for Asymptote? + + + +File: asy-faq.info, Node: Question 7.1, Next: Question 7.2, Previous: Question 6.20, Up: Section 7 + +Question 7.1. Is Asymptote an interpreter or a compiler? + +Asymptote compiles Asymptote commands into its own virtual machine code. +It then runs this pseudocode on a virtual machine to produce PostScript +code. + + +File: asy-faq.info, Node: Question 7.2, Next: Question 7.3, Previous: Question 7.1, Up: Section 7 + +Question 7.2. What is the difference between a frame and a picture? + +Frames are canvases for drawing in PostScript coordinates. While working +with frames directly is occasionally necessary for constructing deferred +drawing routines, pictures are usually more convenient to work with. See +*Note Question 8.8:: `In MetaPost, it is possible to have a drawing remain +the same size in different pictures by defining a unit u and explicitly +multiply all the coordinates by u. Is there a better way to do this in +Asymptote?'. + + +File: asy-faq.info, Node: Question 7.3, Next: Question 7.4, Previous: Question 7.2, Up: Section 7 + +Question 7.3. What is the difference between a path and a guide? + +A path is a cubic spline with fixed endpoint conditions. + +A guide is an unresolved cubic spline (list of cubic-spline nodes and +control points). A guide is like a path except that the computation of the +cubic spline is deferred until drawing time (when it is resolved into a +path); this allows two guides with free endpoint conditions to be joined +together smoothly. + + +File: asy-faq.info, Node: Question 7.4, Next: Question 7.5, Previous: Question 7.3, Up: Section 7 + +Question 7.4. What is a convenient way to declare and initialize an array of pictures? + +You could write yourself a routine such as: +picture[] picture(int n) { + picture[] pic; + for(int i=0; i < n; ++i) { + pic[i]=new picture; + size(pic[i],19cm,0); + } + return pic; +} + +picture[] pic=picture(6); + +File: asy-faq.info, Node: Question 7.5, Next: Question 7.6, Previous: Question 7.4, Up: Section 7 + +Question 7.5. Is there a way to define functions that act on arrays in general (i.e. work for arrays of any type)? + +Generic types aren't yet implemented. + +But for now you can at least say +typedef string T; +include F; + +typedef real T; +include F; +where F.asy contains some type-dependent code like +T[] operator $(T A, T B) {return new T[] {A,B};} + +File: asy-faq.info, Node: Question 7.6, Next: Question 7.7, Previous: Question 7.5, Up: Section 7 + +Question 7.6. Is there any way to declare structures ahead of their definition, e.g. where struct A performs some operation on struct B, but B contains an A member? + +Asymptote does not support forward declaration of types. You can, however, +nest structures, so that both types are visible for parts of the bodies of +both structure definitions. For example: + +struct B { + typedef void someroutine(B b); + + static struct A { + someroutine routine; + void operator init(someroutine routine) { + this.routine=routine; + } + } + + string test="Testing"; +} + +typedef B.A A; + +A a=B.A(new void(B b){write(b.test);}); + +B b; +a.routine(b); + +File: asy-faq.info, Node: Question 7.7, Next: Question 7.8, Previous: Question 7.6, Up: Section 7 + +Question 7.7. Where are static variables in for loops allocated? + +In the example + +void f() { + for(int i=0; i < 3; ++i) { + static int n; + ++n; + write(n); + } +} + +f(); // Writes 1, 2, 3 +the static qualifier means that n is allocated not just outside of the for +loop, but also outside the function. This is clear if you call f multiple +times; there is still only one instance of n. + +The "level" of a variable (where it is allocated) has nothing to do with +the "scope" of a variable (how long it can be referred to by name). The +curly braces enclosing a block affect only a variable's scope, not its +level. + +Static modifiers are meaningless at the top level; they generate a warning +and are simply ignored: + +for(int i=0; i < 3; ++i) { + static int n; + ++n; + write(n); +} +// Writes warning about top-level static modifier and then 1, 1, 1 +Since version 1.22, non-static variables allocated in a loop body are +allocated anew every iteration. This is only noticable in obscure cases +where a variable in a loop is accessed in the closure of a function +defined in the loop: + +int f(); + +for(int i=0; i < 10; ++i) { + int j=10*i; + if(i == 5) + f=new int() {return j;}; +} + +write(f()); // Writes 50 +Variables in the body of a loop last as long as that iteration of the +loop, unless they are kept alive by a function closure as in the example +above. In a function body, variables will last at least as long as the +function call, though because of closures and garbage collection, they may +last longer than that. If defined at the top level of a file or at the +interactive prompt, they will last at least until the end of the file or +prompt's run. + + +File: asy-faq.info, Node: Question 7.8, Next: Question 7.9, Previous: Question 7.7, Up: Section 7 + +Question 7.8. Is there a debugger for asy? + +Yes, Asymptote includes a line-based debugger: + +http://asymptote.sourceforge.net/doc/Debugger.html + + +File: asy-faq.info, Node: Question 7.9, Next: Question 8.1, Previous: Question 7.8, Up: Section 7 + +Question 7.9. Do you accept patches for Asymptote? + +Yes, in fact we would prefer that users submit patches for customized +features (to http://sourceforge.net/tracker/?atid=685685&group_id=120000) +instead of relying on us to do all of the coding. Development will proceed +faster that way. + + +File: asy-faq.info, Node: Section 8, Next: Section 9, Previous: Section 7, Up: Top + +Questions about differences between Asymptote and MetaPost + +* Menu: +* Question 8.1:: What is the equivalent of the MetaPost c[a,b] + interpolation operator? +* Question 8.2:: How does picture scaling differ in Asymptote and + MetaPost? +* Question 8.3:: How can I avoid automatic scaling of a picture? +* Question 8.4:: What is the equivalent of MetaPost ... command? +* Question 8.5:: What is the equivalent of the MetaPost pickup command? +* Question 8.6:: What is the equivalent of the MetaPost whatever + command? +* Question 8.7:: What is the equivalent for the MetaPost command for + lray - horiz*v - verti*u = whatever*(LightSource - R), + a system of three linear equations for three unknowns: + horiz, verti, whatever? +* Question 8.8:: In MetaPost, it is possible to have a drawing remain + the same size in different pictures by defining a unit + u and explicitly multiply all the coordinates by u. Is + there a better way to do this in Asymptote? +* Question 8.9:: In MetaPost, one could produce tiling pictures by + generating a picture, and then clipping the picture to + a rectangle of fixed dimensions around the center of + the picture. How is that done in Asymptote? + + + +File: asy-faq.info, Node: Question 8.1, Next: Question 8.2, Previous: Question 7.9, Up: Section 8 + +Question 8.1. What is the equivalent of the MetaPost c[a,b] interpolation operator? + +interp(a,b,c); + +File: asy-faq.info, Node: Question 8.2, Next: Question 8.3, Previous: Question 8.1, Up: Section 8 + +Question 8.2. How does picture scaling differ in Asymptote and MetaPost? + +Asymptote includes an optional facility to do automatic scaling of +pictures to achieve a given overall picture size, whereas Metapost only +supports manual scaling. Asymptote defers drawing of objects drawn to +pictures and distinguishes between true-size objects and objects that +should scale with the picture size. The resulting linear programming +problem is solved via the Simplex method. + +See the http://asymptote.sourceforge.net/gallery/dimension.asy example for +an example of how deferred drawing is used to accomodate both user and +true-size (PostScript) coordinates. + + +File: asy-faq.info, Node: Question 8.3, Next: Question 8.4, Previous: Question 8.2, Up: Section 8 + +Question 8.3. How can I avoid automatic scaling of a picture? + +If you really like Metapost-style manual (hard-wired) scaling either: + +(i) use the default size(0,0) for the entire picture and do all of the +scaling by hand, just like in MetaPost; + +(ii) draw to a separate picture pic and add(pic.fit()); + +(iii) use frames. + + +File: asy-faq.info, Node: Question 8.4, Next: Question 8.5, Previous: Question 8.3, Up: Section 8 + +Question 8.4. What is the equivalent of MetaPost ... command? + +The connector :: is a macro for tension atleast 1: + +size(100); +pair z0=(0,0); +pair z1=(1,0.25); +pair z2=(2,0); +draw(z0{up}::z1{right}::z2{down}); + +File: asy-faq.info, Node: Question 8.5, Next: Question 8.6, Previous: Question 8.4, Up: Section 8 + +Question 8.5. What is the equivalent of the MetaPost pickup command? + +Just say, for example: + +currentpen=red; + +File: asy-faq.info, Node: Question 8.6, Next: Question 8.7, Previous: Question 8.5, Up: Section 8 + +Question 8.6. What is the equivalent of the MetaPost whatever command? + +Asymptote does not implicitly solve linear equations and therefore does +not have the notion of a whatever unknown. Such a facility could certainly +be added (perhaps using the notation ?= since = means assignment). +However, the most common uses of whatever in MetaPost are covered by +functions like extension in math.asy: +pair extension(pair P, pair Q, pair p, pair q); +this returns the intersection point of the extensions of the line segments +PQ and pq. We find using routines like extension more explicit and less +confusing to new users. But we could be persuaded to add something similar +if someone can justify the need. In the meantime, one can always use the +explicit built-in linear solver solve (see +http://asymptote.sourceforge.net/doc/solve.html), which uses LU +decomposition. + + +File: asy-faq.info, Node: Question 8.7, Next: Question 8.8, Previous: Question 8.6, Up: Section 8 + +Question 8.7. What is the equivalent for the MetaPost command for lray - horiz*v - verti*u = whatever*(LightSource - R), a system of three linear equations for three unknowns: horiz, verti, whatever? + +Since horiz*v+verti*u spans a plane, you could use +real intersect(vector P, vector Q, vector n, vector Z); +to find the intersection time for the line lray-whatever*(LightSource - +R) and then extract the three desired values from there. (You'll still +need to use the built-in explicit linear solver to solve a 2x2 system to +get horiz and verti.) + + +File: asy-faq.info, Node: Question 8.8, Next: Question 8.9, Previous: Question 8.7, Up: Section 8 + +Question 8.8. In MetaPost, it is possible to have a drawing remain the same size in different pictures by defining a unit u and explicitly multiply all the coordinates by u. Is there a better way to do this in Asymptote? + +Yes, Asymptote has a better way: you definitely don't want to manually +scale all of your coordinates. To make the user coordinates represent +multiples of exactly 1cm: + +unitsize(1cm); +draw(unitsquare); +One can also specify different x and y unit sizes: + +unitsize(x=1cm,y=2cm); +draw(unitsquare); +Another way is to draw your fixed size object to a frame and add it to +currentpicture like this: + +path p=(0,0)--(1,0); +frame object; +draw(object,scale(100)*p); + +add(object); +add(object,(0,-10)); +To understand the difference between frames and pictures, try this: + +size(300,300); + +path p=(0,0)--(1,0); +picture object; +draw(object,scale(100)*p); + +add(object); +add(object,(0,-10)); // Adds truesize object to currentpicture + +File: asy-faq.info, Node: Question 8.9, Next: Question 9.1, Previous: Question 8.8, Up: Section 8 + +Question 8.9. In MetaPost, one could produce tiling pictures by generating a picture, and then clipping the picture to a rectangle of fixed dimensions around the center of the picture. How is that done in Asymptote? + +If you are using currentpicture the way one would in MetaPost (drawing in +raw PostScript coordinates), you can simply do something like: + +fill((0,0)--(100,100)--(200,0)--cycle); + +pair center(picture pic=currentpicture) {return 0.5*(pic.min()+pic.max());} + +real height=100; +real width=100; +pair delta=0.5(width,height); +pair c=center(); +clip(box(c-delta,c+delta)); +However, drawing in PostScript coordinates is often inconvenient. Here's +the Asymptote way of doing the same thing, using deferred drawing: + +size(200,100); +fill((0,0)--(1,1)--(2,0)--cycle); + +void clip(picture pic=currentpicture, real width, real height) +{ + pic.clip(new void (frame f, transform) { + pair center=0.5(min(f)+max(f)); + pair delta=0.5(width,height); + clip(f,box(center-delta,center+delta)); + }); +} + +clip(100,100); +See also the discussion of tilings in the documentation: +http://asymptote.sourceforge.net/doc/Pens.html. + + +File: asy-faq.info, Node: Section 9, Previous: Section 8, Up: Top + +Questions about output + +* Menu: +* Question 9.1:: How can I disable automatic invocation of the PS + viewer after an asy file is done processing? +* Question 9.2:: How do I output jpeg images? +* Question 9.3:: Can I embed bitmaps (photos) into my drawings and + position and scale them? +* Question 9.4:: Does Asymptote support direct PDF output? +* Question 9.5:: How to I produce large pictures of high quality in + raster format (e.g. png, giff etc). +* Question 9.6:: Is it possible to produce multi-page documents with + asymptote? + + + +File: asy-faq.info, Node: Question 9.1, Next: Question 9.2, Previous: Question 8.9, Up: Section 9 + +Question 9.1. How can I disable automatic invocation of the PS viewer after an asy file is done processing? + +It's actually not on by default, unless you happen to be using Microsoft +Windows (because that is what most Microsoft Windows users expect). +Microsoft Windows users can turn this feature off with the command-line +option -noV or by putting + +import settings; +interactiveView=false; +batchView=false; +in their config.asy file. See +http://asymptote.sourceforge.net/doc/Options.html. + + +File: asy-faq.info, Node: Question 9.2, Next: Question 9.3, Previous: Question 9.1, Up: Section 9 + +Question 9.2. How do I output jpeg images? + +If you have the ImageMagick convert program installed, simply type + +asy -f jpg test.asy + +File: asy-faq.info, Node: Question 9.3, Next: Question 9.4, Previous: Question 9.2, Up: Section 9 + +Question 9.3. Can I embed bitmaps (photos) into my drawings and position and scale them? + +Convert them to eps format and use the graphic(string) function just like +a Label: + +label(graphic("file"),(0,0)); +See the example http://asymptote.sourceforge.net/gallery/orthocenter.asy +and http://asymptote.sourceforge.net/doc/label.html. + + +File: asy-faq.info, Node: Question 9.4, Next: Question 9.5, Previous: Question 9.3, Up: Section 9 + +Question 9.4. Does Asymptote support direct PDF output? + +Yes, PDF output can be produced by the -f pdf option or -tex pdflatex +option. This supports transparency, annotations, embedded movies, and +U3D/PRC content. + + +File: asy-faq.info, Node: Question 9.5, Next: Question 9.6, Previous: Question 9.4, Up: Section 9 + +Question 9.5. How to I produce large pictures of high quality in raster format (e.g. png, giff etc). + +Try using some of the options to convert, mainly -geometry and -density. +For example: +convert -geometry 1000x3000 example.eps example.png +You can also change the default resolution of the image with: +convert -geometry 1000x3000 -density 300 -units PixelsPerInch example.eps example.png +This does not change the number of pixels in the image, but just gives a +hint as to how large each pixel should be displayed. + +If you include the -density option without the -geometry option, convert +will keep the image size constant (so a 4cm x 3cm eps figure will +generate a 4cm x 3cm png image). + + +File: asy-faq.info, Node: Question 9.6, Previous: Question 9.5, Up: Section 9 + +Question 9.6. Is it possible to produce multi-page documents with asymptote? + +Yes, simply call the newpage() function. This is used by the slide.asy +package to produce high-quality slide presentations (easier to use than +Prosper). + |