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authorKarl Berry <karl@freefriends.org>2018-03-03 21:54:53 +0000
committerKarl Berry <karl@freefriends.org>2018-03-03 21:54:53 +0000
commit49b02bd2f9b2cd0ef834c72850e519a9bec4ccd5 (patch)
treeae8dfaac64fc548e3b422ea7adefd92501aeb374 /Master/texmf-dist/doc/latex/polexpr/polexpr.txt
parentb482212984105cf874198fd412f9dbb70f1565b8 (diff)
polexpr (3mar18)
git-svn-id: svn://tug.org/texlive/trunk@46805 c570f23f-e606-0410-a88d-b1316a301751
Diffstat (limited to 'Master/texmf-dist/doc/latex/polexpr/polexpr.txt')
-rw-r--r--Master/texmf-dist/doc/latex/polexpr/polexpr.txt43
1 files changed, 19 insertions, 24 deletions
diff --git a/Master/texmf-dist/doc/latex/polexpr/polexpr.txt b/Master/texmf-dist/doc/latex/polexpr/polexpr.txt
index fe99d075a49..16cdff04d1e 100644
--- a/Master/texmf-dist/doc/latex/polexpr/polexpr.txt
+++ b/Master/texmf-dist/doc/latex/polexpr/polexpr.txt
@@ -4,7 +4,7 @@
Package polexpr documentation
===============================
-0.4.1 (2018/03/01)
+0.4.2 (2018/03/03)
==================
.. contents::
@@ -1521,36 +1521,27 @@ Technicalities
can use `\\PolDef{f}{P(x)} <PolDef_>`_
rather. The colon in ``:=`` may be active with no consequences.
-- During execution of polynomial operations by ``\poldef`` (but not
- during the initial purely numerical parsing of the expression), the
- xintfrac_ macro ``\xintAdd`` is temporarily patched to always express
- ``a/b + c/d`` with ``lcm(b,d)`` as denominator. Indeed the current
- (xint 1.2p) ``\xintAdd`` uses ``(ad+bc)/bd`` formula except if ``b``
- divides ``d`` or ``d`` divides ``b``, which quickly leads in real life
- to big denominators.
-
- It is probable that this convention will be backported as default
- behaviour of xintfrac's ``\xintAdd`` in a future xint release. When this
- change is merged, there will be an impact on coefficients computed by
- ``\poldef`` because the change will apply even to the pure numerical
- evaluations arising during the initial stage of the parsing. Of course
- the coefficients are still the same rational numbers, only
- representation as fractions may change.
-
-- As a consequence of previous rule, user-chosen common denominators
- survive addition and multiplications::
+- As a consequence of xintfrac_ addition and subtraction always using
+ least common multiples for the denominators [#]_, user-chosen common
+ denominators survive additions and multiplications. For example, this::
\poldef P(x):= 1/2 + 2/2*x + 3/2*x^3 + 4/2*x^4;
\poldef Q(x):= 1/3 + (2/3)x + (3/3)x^3 + (4/3)x^4;
\poldef PQ(x):= P(x)Q(x);
- gives the polynomial::
+ gives internally the polynomial::
1/6+4/6*x^1+4/6*x^2+6/6*x^3+20/6*x^4+16/6*x^5+9/6*x^6+24/6*x^7+16/6*x^8
- where all coefficients have the same denominator 6 (which in this
- example is the least common multiple of the denominators of the
- reduced coefficients.)
+ where all coefficients have the same denominator 6. Notice though that
+ ``\PolToExpr{PQ}`` outputs the ``6/6*x^3`` as ``x^3`` because (by
+ default) it recognizes and filters out coefficients equal to one or
+ minus one (since release ``0.3``). One can use for example
+ ``\PolToCSV{PQ}`` to see the internally stored coefficients.
+
+ .. [#] prior to ``0.4.1``, ``polexpr`` used to temporarily patch
+ during the parsing of polynomials the xintfrac_ macros. This
+ patch was backported to xint_ at release ``1.3``.
- `\\PolDiff{polname_1}{polname_2}`_ always applies ``\xintIrr`` to the
resulting coefficients, except that the *power of ten* part ``[N]``
@@ -1738,11 +1729,15 @@ CHANGE LOG
The main new feature is implementation of the `Sturm algorithm`_
for localization of the real roots of polynomials.
-
- v0.4.1 (2018/03/01)
Synced with xint 1.3.
+- v0.4.2 (2018/03/03)
+
+ Documentation fix.
+
+
Acknowledgments
---------------