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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">

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 <H1 ALIGN="CENTER">probsoln.sty v2.04: L<SUP><SMALL>A</SMALL></SUP>T<SMALL>E</SMALL>X2<SUB>e</SUB> Package to help create problem sheets</H1>
<P ALIGN="CENTER"><STRONG>Nicola L.C. Talbot</STRONG></P>
<P ALIGN="CENTER"><STRONG>21st August 2007</STRONG></P>
 <BR>

<H2><A NAME="SECTION00010000000000000000">
Contents</A>
</H2>
<!--Table of Contents-->

<UL>
<LI><A NAME="tex2html18"
  HREF="#SECTION00020000000000000000">Introduction</A>
<LI><A NAME="tex2html19"
  HREF="#SECTION00030000000000000000">Package Options</A>
<LI><A NAME="tex2html20"
  HREF="#SECTION00040000000000000000">Creating a New Problem</A>
<LI><A NAME="tex2html21"
  HREF="#SECTION00050000000000000000">Creating a Database</A>
<LI><A NAME="tex2html22"
  HREF="#SECTION00060000000000000000">Displaying a Problem</A>
<LI><A NAME="tex2html23"
  HREF="#SECTION00070000000000000000">Selecting All Problems</A>
<LI><A NAME="tex2html24"
  HREF="#SECTION00080000000000000000">Selecting Problems at Random</A>
<LI><A NAME="tex2html25"
  HREF="#SECTION00090000000000000000">Other Commands</A>
<LI><A NAME="tex2html26"
  HREF="#SECTION000100000000000000000">Troubleshooting</A>
<UL>
<LI><A NAME="tex2html27"
  HREF="#SECTION000101000000000000000">Unexpected Output</A>
<LI><A NAME="tex2html28"
  HREF="#SECTION000102000000000000000">Error Messages</A>
</UL>
<BR>
<LI><A NAME="tex2html29"
  HREF="#SECTION000110000000000000000">Contact Details</A>
<LI><A NAME="tex2html30"
  HREF="#SECTION000120000000000000000">Index</A>
</UL>
<!--End of Table of Contents-->
<P>

<H1><A NAME="SECTION00020000000000000000">
Introduction</A>
</H1>
The <TT>probsoln</TT> package is designed for teachers or
lecturers who want to create problem sheets for their 
students.  This package was designed with specifically 
mathematics problems in mind, but can be used for other 
subjects as well.  The idea is to create a file containing a
large number of problems with their solutions which can be 
read in by L<SUP><SMALL>A</SMALL></SUP>T<SMALL>E</SMALL>X, and then select a number of problems to
typeset.  This means that once the database has been set up,
each year you can easily create a new problem sheet that is
sufficiently different from the previous year, thus
preventing the temptation of current students seeking out
the previous year's students, and checking out their
answers.  There is also an option that can be passed to the
package to determine whether or not the solutions should be
printed.  In this way, one file can either produce the
student's version or the teacher's version.

<P>

<H1><A NAME="SECTION00030000000000000000">
Package Options</A>
</H1>
The following options may be passed to this package:
<DIV ALIGN="CENTER">
<TABLE CELLPADDING=3>
<TR><TD ALIGN="LEFT"><TT></TD><TD ALIGN="LEFT">answers </TT></TD>
<TD ALIGN="LEFT">Show the answers</TD>
</TR>
<TR><TD ALIGN="LEFT"><TT></TD><TD ALIGN="LEFT">noanswers </TT></TD>
<TD ALIGN="LEFT">Don't show the answers (default)</TD>
</TR>
</TABLE>
</DIV>

<P>

<H1><A NAME="SECTION00040000000000000000">
Creating a New Problem</A>
</H1>

<A NAME="newproblem"></A><TT>newproblem</TT><A NAME="386"></A><code>[</code><I>nargs</I><code>]{</code><I>label</I><code>}{</code><I>problem</I><code>}{</code><I>solution</I><code>}</code>
<BR>
<BR>
A new problem is defined using the command 
<TT>&#92;newproblem</TT><A NAME="389"></A>.  This does not print anything,
but merely stores the problem. As from version 2.03, there is also
a starred version of this command for problems without a solution
(for example, essay style questions):
<BR>
<BR>
<A NAME="newproblem_"></A><TT>newproblem*</TT><A NAME="393"></A><code>[</code><I>nargs</I><code>]{</code><I>label</I><code>}{</code><I>problem</I><code>}</code>
<BR>
<BR>
The argument <I>label</I> is
a unique string that is assigned to this problem so that it
can be used later.  The argument <I>problem</I> is normal 
L<SUP><SMALL>A</SMALL></SUP>T<SMALL>E</SMALL>X code that should be used to typeset the problem.  
The argument <I>solution</I> is normal L<SUP><SMALL>A</SMALL></SUP>T<SMALL>E</SMALL>X code that
should be used to typeset the solution, if required.  For
example, the following defines a problem with the label 
<A NAME="quaddiff"></A><TT>quaddiff</TT>:
<PRE>
 \newproblem{quaddiff}{%
 %This is the problem
 \begin{displaymath}
 f(x) = x^2 + 3x + 4
 \end{displaymath}
 }{%
 %This is the solution
 \begin{displaymath}
 f'(x) = 2x + 3
 \end{displaymath}
 }
</PRE>
The following is an essay question, so doesn't come with a solution:
<PRE>
\newproblem*{inheritance}{Describe what is meant by the term 
\emph{inheritance} in object-oriented programming. Use examples.}
</PRE>

<P>
The optional argument <I>nargs</I> specifies the number of
parameters this problem will take.  By default this value is
0, but any value from 1 to 9 may be used.  Each parameter is
referred to by <code>#1</code>, <code>#2</code>, ..., <code>#9</code>.
For example, the following problem, labelled <A NAME="sindiff"></A><TT>sindiff</TT>, 
takes one parameter:
<PRE>
\newproblem[1]{sindiff}{%
\(f(x) = \sin(#1x)\)
}{%
\(f'(x) = #1\cos(#1x)\)
}
</PRE>

<P>
The <A HREF="#quaddiff"><TT>quaddiff</TT></A> problem shown above can be made more
generic by using parameters<A NAME="diff:quad"></A>:
<PRE>
\newcount\ctr
\newproblem[3]{diff:quad}{%
\(f(x) = 
\ifnum#1=0
\else
\ifnum#1=1\else#1\fi x^2 
\fi
\ifnum#2=0
\else
\ifnum#2&gt;0 \ifnum#1=0 \else + \fi \fi
\ifnum#2=1\else#2\fi x 
\fi
\ifnum#3=0
\else
\ifnum#3&gt;0 \ifnum#2=0 \ifnum#1=0 \else + \fi \else + \fi\fi
#3
\fi\)
}{%
\(f'(x) = 
\ifnum#1=0
\else
\ctr=2
\multiply\ctr by #1
\the\ctr x 
\fi
\ifnum#2=0
\else
\ifnum#2&gt;0 \ifnum#1=0 \else + \fi \fi
#2
\fi
 % print 0 if both #1 and #2 are 0
\ifnum#1=0 \ifnum#2=0 0 \fi\fi 
\)
}
</PRE>
The three parameters correspond to the coefficients.  Note
that they must all be integers since T<SMALL>E</SMALL>X only performs
integer arithmetic.

<P>

<H1><A NAME="SECTION00050000000000000000">
Creating a Database</A>
</H1>

<P>
To generate a database, simply create a <TT>.tex</TT> file
where all the problems are defined using <A HREF="#newproblem"><TT>newproblem</TT><A NAME="407"></A></A> or
<A HREF="#newproblem_"><TT>newproblem*</TT><A NAME="412"></A></A>,
and either <TT>&#92;input</TT><A NAME="415"></A> it at the start of your document if
you want to use <A HREF="#sec:useprob">specific problems</A>, or pass it to 
<A HREF="#sec:selran"><TT>&#92;selectrandomly</TT><A NAME="421"></A></A>. This package
comes with some sample databases, along with some sample documents
that use these databases.

<P>

<H1><A NAME="SECTION00060000000000000000"></A>
<A NAME="sec:useprob"></A>
<BR>
Displaying a Problem
</H1>
 
<A NAME="useproblem"></A><TT>useproblem</TT><A NAME="425"></A><code>{</code><I>label</I><code>}</code>
<BR>
<BR>
Once a problem has been defined using <A HREF="#newproblem"><TT>newproblem</TT><A NAME="430"></A></A>, it 
can be typeset using the command <TT>&#92;useproblem</TT><A NAME="433"></A>.  If the
problem was defined to take arguments, the arguments to the
problem should come after the label.  In the case of the
<A HREF="#sindiff"><TT>sindiff</TT></A> example above, the command 
<code>\useproblem{sindiff}{2}</code> would produce the following:
<BR>
<BR> <I>f</I>(<I>x</I>) = sin(2<I>x</I>)
 
<H4><A NAME="SECTION00060010000000000000">
Solution:</A>
</H4> <I>f'</I>(<I>x</I>) = 2cos(2<I>x</I>)
<BR>
<BR>
whereas the command <code>\useproblem{diff:quad}{3}{0}{-2}</code> would produce:
<BR>
<BR> <I>f</I>(<I>x</I>) = 3<I>x</I><SUP>2</SUP> - 2
 
<H4><A NAME="SECTION00060020000000000000">
Solution:</A>
</H4> <I>f'</I>(<I>x</I>) = 6<I>x</I>
<BR>
<BR>

<P>
Suppose all the above problems are defined in the file 
<TT>probs.tex</TT>, then the following code will create a
problem sheet with four questions in it:
<PRE>
\documentclass{article}

\usepackage{probsoln}
\input{probs}

\begin{document}
Differentiate the following functions with respect to $x$:
\begin{enumerate}
\item \useproblem{quaddiff}
\item \useproblem{sindiff}{4}
\item \useproblem{diff:quad}{2}{3}{1}
\item \useproblem{diff:quad}{0}{1}{2}
\end{enumerate}
\end{document}
</PRE>
The answer sheet can then be generated by passing the option
<TT>answers</TT> to the <TT>probsoln</TT> package.

<P>

<H1><A NAME="SECTION00070000000000000000">
Selecting All Problems</A>
</H1>

<P>
To select all problems defined in a database, in the order in
which they were defined, use the command:

<A NAME="selectallproblems"></A><TT>selectallproblems</TT><A NAME="440"></A><code>{</code><I>filename</I><code>}</code>
For example, suppose the problems are defined in the file
<TT>easy.tex</TT>, then the following will create a problem sheet 
which uses all these problems:
<PRE>
\documentclass[a4paper]{article}

\usepackage{probsoln}

\begin{document}
Differentiate the following functions:
\begin{enumerate}
\selectallproblems{easy}
\end{enumerate}
\end{document}
</PRE>

<P>

<H1><A NAME="SECTION00080000000000000000"></A>
<A NAME="sec:selran"></A>
<BR>
Selecting Problems at Random
</H1>
 
<A NAME="selectrandomly"></A><TT>selectrandomly</TT><A NAME="444"></A><code>{</code><I>filename</I><code>}{</code><I>n</I><code>}</code>
<BR>
<BR>
The command <TT>&#92;selectrandomly</TT><A NAME="447"></A> will select <I>n</I>
problems that are defined in the file <I>filename</I>.  Each
problem is proceeded by 
<A NAME="PSitem"></A><TT>PSitem</TT><A NAME="451"></A> which is
defined to be <TT>&#92;item</TT><A NAME="454"></A>, so the command 
<TT>&#92;selectrandomly</TT><A NAME="457"></A> should occur within one of the
list-like environments, such as <TT>enumerate</TT>.  
For example:
<PRE>
\begin{enumerate}
\selectrandomly{easy.tex}{4}
\end{enumerate}
</PRE>
will result in four numbered problems, selected at random
from the file <TT>easy.tex</TT>. (The <TT>.tex</TT> extension
may be omitted.) Each problem is followed by the command
<A NAME="endPSNitem"></A><TT>endPSNitem</TT><A NAME="461"></A> which by default does nothing.

<P>
Multiple <TT>&#92;selectrandomly</TT><A NAME="464"></A> commands may be used, however a
different file must be used each time.  For
example:
<PRE>
\begin{enumerate}
\item Differentiate the following functions with respect to $x$:

\begin{enumerate}
\selectrandomly{samples/easy.tex}{3}
\selectrandomly{samples/args.tex}{1}
\end{enumerate}

\selectrandomly{samples/implicit.tex}{1}
\selectrandomly{samples/1stprncpl.tex}{1}

\end{enumerate}
</PRE>
This will result in a total of 6 problems, numbered 1(a),
1(b), 1(c), 1(d), 2 and 3.

<P>
If a randomly selected problem requires arguments, a message
similar to the following will be displayed:
<PRE>
Problem diff:quad requires 3 argument(s), please specify (e.g. {5}{3}):
</PRE>
Enter the required arguments, where each argument is
enclosed in braces ({ }).

<P>

<H1><A NAME="SECTION00090000000000000000">
Other Commands</A>
</H1>

The command <A NAME="PSNrandseed"></A><TT>PSNrandseed</TT><A NAME="468"></A><code>{</code><I>n</I><code>}</code> specifies 
the seed for the random number generator.  For example,
if you are using <A HREF="#selectrandomly"><TT>selectrandomly</TT><A NAME="473"></A></A>,
<code>\PSNrandseed{\year}</code> will produce a different set of
problems each year, whereas <code>\PSNrandseed{\time}</code>
will produce a different set of problems each time you 
L<SUP><SMALL>A</SMALL></SUP>T<SMALL>E</SMALL>X the problem sheet (as long as you leave at least a
minute between runs.)

<P>
The command <A NAME="random"></A><TT>random</TT><A NAME="477"></A><code>{</code><I>counter</I><code>}{</code><I>a</I><code>}{</code><I>b</I><code>}</code>
generates a random number from <I>a</I> to <I>b</I> and
stores it in the L<SUP><SMALL>A</SMALL></SUP>T<SMALL>E</SMALL>X counter <I>counter</I>. For example,
to select 2, 3 or 4 problems from the file
<TT>implicit.tex</TT>:
<PRE>
\newcounter{numproblems}
\begin{enumerate}
\random{numproblems}{2}{4}
\selectrandomly{implicit.tex}{\value{numproblems}}
\end{enumerate}
</PRE>
(Note the use of <TT>&#92;value</TT><A NAME="480"></A>.)

<P>
This command can also be used to generate random values for
problems that take arguments. Consider the problem <A HREF="#diff:quad"><TT>diff:quad</TT></A>
defined earlier. Three counters can be defined to represent the
three coefficients:
<PRE>
\newcounter{A}
\newcounter{B}
\newcounter{C}
</PRE>
Random values can now be assigned to these counters:
<PRE>
\random{A}{-5}{5}
\random{B}{-5}{5}
\random{C}{-5}{5}
</PRE>
Finally, the problem can be used (note the use of <TT>&#92;arabic</TT><A NAME="486"></A>):
<PRE>
\useproblem{diff:quad}{\arabic{A}}{\arabic{B}}{\arabic{C}}
</PRE> 

<P>
The command 
<A NAME="doforrandN"></A><TT>doforrandN</TT><A NAME="490"></A><code>{</code><I>n</I><code>}{</code><I>cmd</I><code>}{</code><I>list</I><code>}{</code><I>text</I><code>}</code> will apply
<I>text</I> for a random selection of <I>n</I> items in the
comma separated <I>list</I>. In each iteration the list
item is denoted by <I>cmd</I>. For example, suppose you 
have three files called <TT>file1.tex</TT>, 
<TT>file2.tex</TT> and <TT>file3.tex</TT>, and you want to
select 1 problem from two of the three files, then you can
do:
<PRE>
\doforrandN{2}{\file}{file1,file2,file3}{\selectrandomly{\file}{1}}
</PRE>
Note that it is also possible to do
<PRE>
\newcounter{numproblems}
\random{numproblems}{1}{3}
\selectrandomly{file\arabic{numproblems}}{1}
\random{numproblems}{1}{3}
\selectrandomly{file\arabic{numproblems}}{1}
</PRE>
however there is a possibility that the same file may be
selected twice which will cause an error.

<P>
The command <A NAME="showanswers"></A><TT>showanswers</TT><A NAME="494"></A> will show the solutions from
that point on.  May be localised by placing within a group.

<P>
The command <A NAME="hideanswers"></A><TT>hideanswers</TT><A NAME="498"></A> will hide the solutions from
that point on.  May be localised by placing within a group.

<P>
The solution is placed inside the <TT>solution</TT> 
environment. By default this environment simply does
<code>\par\noindent\textbf{\solutionname:} </code> at the start, where 
<A NAME="solutionname"></A><TT>solutionname</TT><A NAME="503"></A>
has the value: Solution. See the file <TT>sample3.tex</TT>, which
comes with this package, for an illustration of how to 
customise the way in which the randomly selected problems are
displayed. This sample file randomly selects multiple choice
problems stored in the file <TT>tabmchoice.tex</TT>, and displays them
in a longtable <TT>environment</TT>. As from version 2.03, the package 
will not define this environment if another package or class file has
already defined it.

<P>
The boolean variable <TT>showanswers</TT> is defined to be
true if the answers are shown and false otherwise.  You can
therefore do something like:
<PRE>
\ifthenelse{\boolean{showanswers}}{\textbf{Solution Sheet}}{}
</PRE>
and <B>Solution Sheet</B> will be printed only if the
answers are displayed.  (For more information on 
<TT>&#92;ifthenelse</TT><A NAME="507"></A> and <TT>&#92;boolean</TT><A NAME="510"></A> see the 
documentation for the <TT>ifthen</TT> package by 
David Carlisle.)

<P>
The <TT>showanswers</TT> switch can also be used within the definition
of a problem, if you want the question to appear differently if the
solution is displayed. For example:
<PRE>
\newproblem{mc:prod}{%
Which of the following is the derivative of $x\sin(x)$?
(Circle the correct answer.)
\ifthenelse{\boolean{showanswers}}{}%
{\begin{description}
\item[A] $\sin(x)$
\item[B] $x\cos(x)$
\item[C] $\sin(x) + x\cos(x)$
\end{description}
}}{%
\begin{description}
\item[A] $\sin(x)$
\item[B] $x\cos(x)$
\item[\textcircled{C}] $\sin(x) + x\cos(x)$ (product rule).
\end{description}
}
</PRE>
If the solutions are not displayed, the question will appear
as
<DL>
<DT></DT>
<DD>Which of the following is the derivative of 
<I>x</I>sin(<I>x</I>)? 
(Circle the correct answer.)
<DL>
<DT><STRONG>A</STRONG></DT>
<DD>sin(<I>x</I>)
</DD>
<DT><STRONG>B</STRONG></DT>
<DD><I>x</I>cos(<I>x</I>)
</DD>
<DT><STRONG>C</STRONG></DT>
<DD>sin(<I>x</I>)+<I>x</I>cos(<I>x</I>)
</DD>
</DL>
</DD>
</DL>
otherwise it will appear as:
<DL>
<DT></DT>
<DD>Which of the following is the derivative of 
<I>x</I>sin(<I>x</I>)? 
(Circle the correct answer.)
<DL>
<DT><STRONG>A</STRONG></DT>
<DD>sin(<I>x</I>)
</DD>
<DT><STRONG>B</STRONG></DT>
<DD><I>x</I>cos(<I>x</I>)
</DD>
<DT><STRONG><FONT SIZE="+2">&#169;</FONT></STRONG></DT>
<DD>sin(<I>x</I>) + <I>x</I>cos(<I>x</I>) (product rule)
</DD>
</DL>
</DD>
</DL>

<P>

<H1><A NAME="SECTION000100000000000000000">
Troubleshooting</A>
</H1>

<H2><A NAME="SECTION000101000000000000000">
Unexpected Output</A>
</H2>

<UL>
<LI>I have lots of blank space before the first problem when
using <A HREF="#selectrandomly"><TT>selectrandomly</TT><A NAME="515"></A></A>.

<P>
This is probably because you have lots of extraneous white space
in your database. <A HREF="#selectrandomly"><TT>selectrandomly</TT><A NAME="520"></A></A> will input the entire
file, so any extra space will be included. Try commenting out the
extra space using %.
</LI>
</UL>

<P>

<H2><A NAME="SECTION000102000000000000000">
Error Messages</A>
</H2>

<UL>
<LI><TT>! Package probsoln Error: Label ... already used.
</TT>

<P>
Each label identifier used in <A HREF="#newproblem"><TT>newproblem</TT><A NAME="525"></A></A> must be
unique.  Check to make sure you haven't used the same label 
more than once.  Also check to make sure you haven't 
<TT>&#92;input</TT><A NAME="528"></A>ed or randomly selected from the same file more
than once. (Or <TT>&#92;input</TT><A NAME="531"></A>ed and randomly selected from
the same file.)

<P>
</LI>
<LI><TT>! Package probsoln Error: Label ... undefined.
</TT>

<P>
You need to define a problem before you can use it.  Check to
make sure you haven't mis-spelt it, and check to make sure you
have <TT>&#92;input</TT><A NAME="534"></A>ed the file in which it is defined.

<P>
</LI>
<LI><TT>! Package probsoln Error: Requested number too large.
</TT>

<P>
You have asked for more problems than are defined within the
specified file.  All problems in that file will be selected.

<P>
</LI>
<LI><TT>! Package probsoln Error: Can't randomly select <I>n</I>
item(s)
</TT>

<P>
You have asked to randomly select <I>n</I> items from a list
that has less than <I>n</I> elements. For example, the
following will generate this error:
<PRE>
\doforrandN{10}{\file}{file1,file2,file3}{%
\selectrandomly{\file}{1}}
</PRE>
In this case the list, <TT>file1,file2,file3</TT> has only 3
elements, but the user has asked for 10 elements. If you type
`h' at the L<SUP><SMALL>A</SMALL></SUP>T<SMALL>E</SMALL>X prompt it will tell you how many items it thinks
there are in the list. Remember that each item must be separated by a
comma.

<P>
</LI>
<LI><TT>! LaTeX Error: Lonely <TT>&#92;item</TT><A NAME="537"></A>-perhaps missing list
environment.
</TT>

<P>
Each problem selected using <A HREF="#selectrandomly"><TT>selectrandomly</TT><A NAME="542"></A></A> is
proceeded by <A HREF="#PSNitem"><TT>PSNitem</TT><A NAME="547"></A></A> which by default is defined
as <TT>&#92;item</TT><A NAME="550"></A>, and should therefore be 
placed in one of the list environments, such as 
<TT>enumerate</TT>. Alternatively, redefine <A HREF="#PSNitem"><TT>PSNitem</TT><A NAME="555"></A></A>.

<P>
</LI>
<LI>I get an error when I put a command definition in my database
when using <TT>&#92;selectrandomly</TT><A NAME="558"></A>.

<P>
<A HREF="#selectrandomly"><TT>selectrandomly</TT><A NAME="563"></A></A> inputs the database twice, so any 
command definition will be read twice, causing an error. You
can use the switch <TT>&#92;iffirstpass</TT><A NAME="566"></A> to prevent the error. For
example:
<PRE>
\iffirstpass
\newcommand{\mycmd}{}
\fi
</PRE>
It is generally not a good idea to put anything other than
<A HREF="#newproblem"><TT>newproblem</TT><A NAME="571"></A></A> commands within the database.

<P>
</LI>
</UL>

<P>

<H1><A NAME="SECTION000110000000000000000">
Contact Details</A>
</H1>
Dr Nicola Talbot
<BR>
School of Computing Sciences
<BR>
University of East Anglia
<BR>
Norwich. NR4 7TJ
<BR><TT><A NAME="tex2html1"
  HREF="http://theoval.cmp.uea.ac.uk/~nlct/">http://theoval.cmp.uea.ac.uk/~nlct/</A></TT>
<P>
<BR>

<H2><A NAME="SECTION000120000000000000000">
Index</A>
</H2><DL COMPACT>
<DT><STRONG><TT>&#92;arabic</TT></STRONG>
<DD><A HREF="#486">Other Commands</A>
<DT><STRONG><TT>&#92;boolean</TT></STRONG>
<DD><A HREF="#510">Other Commands</A>
<DT><STRONG><TT>&#92;doforrandN</TT></STRONG>
<DD><A HREF="#490">Other Commands</A>
<DT><STRONG><TT>&#92;endPSNitem</TT></STRONG>
<DD><A HREF="#461">Selecting Problems at Random</A>
<DT><STRONG><TT>&#92;hideanswers</TT></STRONG>
<DD><A HREF="#498">Other Commands</A>
<DT><STRONG><TT>&#92;iffirstpass</TT></STRONG>
<DD><A HREF="#566">Error Messages</A>
<DT><STRONG><TT>&#92;ifthenelse</TT></STRONG>
<DD><A HREF="#507">Other Commands</A>
<DT><STRONG><TT>&#92;input</TT></STRONG>
<DD><A HREF="#415">Creating a Database</A>
 | <A HREF="#528">Error Messages</A>
 | <A HREF="#531">Error Messages</A>
 | <A HREF="#534">Error Messages</A>
<DT><STRONG><TT>&#92;item</TT></STRONG>
<DD><A HREF="#454">Selecting Problems at Random</A>
 | <A HREF="#537">Error Messages</A>
 | <A HREF="#550">Error Messages</A>
<DT><STRONG><TT>&#92;newproblem</TT></STRONG>
<DD><A HREF="#386">Creating a New Problem</A>
 | <A HREF="#389">Creating a New Problem</A>
 | <A HREF="#407">Creating a Database</A>
 | <A HREF="#430">Displaying a Problem</A>
 | <A HREF="#525">Error Messages</A>
 | <A HREF="#571">Error Messages</A>
<DT><STRONG><TT>&#92;newproblem*</TT></STRONG>
<DD><A HREF="#393">Creating a New Problem</A>
 | <A HREF="#412">Creating a Database</A>
<DT><STRONG><TT>&#92;PSitem</TT></STRONG>
<DD><A HREF="#451">Selecting Problems at Random</A>
<DT><STRONG><TT>&#92;PSNitem</TT></STRONG>
<DD><A HREF="#547">Error Messages</A>
 | <A HREF="#555">Error Messages</A>
<DT><STRONG><TT>&#92;PSNrandseed</TT></STRONG>
<DD><A HREF="#468">Other Commands</A>
<DT><STRONG><TT>&#92;random</TT></STRONG>
<DD><A HREF="#477">Other Commands</A>
<DT><STRONG><TT>&#92;selectallproblems</TT></STRONG>
<DD><A HREF="#440">Selecting All Problems</A>
<DT><STRONG><TT>&#92;selectrandomly</TT></STRONG>
<DD><A HREF="#418">Creating a Database</A>
 | <A HREF="#421">Creating a Database</A>
 | <A HREF="#444">Selecting Problems at Random</A>
 | <A HREF="#447">Selecting Problems at Random</A>
 | <A HREF="#457">Selecting Problems at Random</A>
 | <A HREF="#464">Selecting Problems at Random</A>
 | <A HREF="#473">Other Commands</A>
 | <A HREF="#515">Unexpected Output</A>
 | <A HREF="#520">Unexpected Output</A>
 | <A HREF="#542">Error Messages</A>
 | <A HREF="#563">Error Messages</A>
 | <A HREF="#558">Error Messages</A>
<DT><STRONG><TT>&#92;showanswers</TT></STRONG>
<DD><A HREF="#494">Other Commands</A>
<DT><STRONG><TT>&#92;solutionname</TT></STRONG>
<DD><A HREF="#503">Other Commands</A>
<DT><STRONG><TT>&#92;useproblem</TT></STRONG>
<DD><A HREF="#425">Displaying a Problem</A>
 | <A HREF="#433">Displaying a Problem</A>
<DT><STRONG><TT>&#92;value</TT></STRONG>
<DD><A HREF="#480">Other Commands</A>

</DL>
<BR><HR>
<ADDRESS>
<A href=http://theoval.cmp.uea.ac.uk/~nlct/>Nicola L. C. Talbot</A>. 
<A HREF=http://www.cmp.uea.ac.uk/>School of Computing Sciences</A>. 
<A HREF=http://www.uea.ac.uk/>University of East Anglia.</A> 
Last Modified: 2007-08-21
</ADDRESS>
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