NAME¶

math::rationalfunctions - Polynomial functions

SYNOPSIS¶

package require Tcl ?8.4?

package require math::rationalfunctions ?1.0.1?

::math::rationalfunctions::rationalFunction num den

::math::rationalfunctions::ratioCmd num den

::math::rationalfunctions::evalRatio rational x

::math::rationalfunctions::addRatio ratio1 ratio2

::math::rationalfunctions::subRatio ratio1 ratio2

::math::rationalfunctions::multRatio ratio1 ratio2

::math::rationalfunctions::divRatio ratio1 ratio2

::math::rationalfunctions::derivPolyn ratio

::math::rationalfunctions::coeffsNumerator ratio

::math::rationalfunctions::coeffsDenominator ratio

DESCRIPTION¶

This package deals with rational functions of one variable:

• the basic arithmetic operations are extended to rational functions
• computing the derivatives of these functions
• evaluation through a general procedure or via specific procedures)

PROCEDURES¶

The package defines the following public procedures:

::math::rationalfunctions::rationalFunction num den

Return an (encoded) list that defines the rational function. A rational function

             1 + x^3


   f(x) = ------------


          1 + 2x + x^2

can be defined via:

   set f [::math::rationalfunctions::rationalFunction [list 1 0 0 1]  [list 1 2 1]]

::math::rationalfunctions::ratioCmd num den

Create a new procedure that evaluates the rational function. The name of the function is automatically generated. Useful if you need to evaluate the function many times, as the procedure consists of a single [expr] command.

::math::rationalfunctions::evalRatio rational x

Evaluate the rational function at x.

::math::rationalfunctions::addRatio ratio1 ratio2

Return a new rational function which is the sum of the two others.

::math::rationalfunctions::subRatio ratio1 ratio2

Return a new rational function which is the difference of the two others.

::math::rationalfunctions::multRatio ratio1 ratio2

Return a new rational function which is the product of the two others. If one of the arguments is a scalar value, the other rational function is simply scaled.

::math::rationalfunctions::divRatio ratio1 ratio2

Divide the first rational function by the second rational function and return the result. The remainder is dropped

::math::rationalfunctions::derivPolyn ratio

Differentiate the rational function and return the result.

::math::rationalfunctions::coeffsNumerator ratio

Return the coefficients of the numerator of the rational function.

::math::rationalfunctions::coeffsDenominator ratio

Return the coefficients of the denominator of the rational function.

REMARKS ON THE IMPLEMENTATION¶

The implementation of the rational functions relies on the math::polynomials package. For further remarks see the documentation on that package.

BUGS, IDEAS, FEEDBACK¶

This document, and the package it describes, will undoubtedly contain bugs and other problems. Please report such in the category math :: rationalfunctions of the Tcllib Trackers [http://core.tcl.tk/tcllib/reportlist]. Please also report any ideas for enhancements you may have for either package and/or documentation.

When proposing code changes, please provide unified diffs, i.e the output of diff -u.

Note further that attachments are strongly preferred over inlined patches. Attachments can be made by going to the Edit form of the ticket immediately after its creation, and then using the left-most button in the secondary navigation bar.

KEYWORDS¶

math, rational functions

CATEGORY¶

Mathematics

COPYRIGHT¶

Copyright (c) 2005 Arjen Markus <arjenmarkus@users.sourceforge.net>