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Math(3) User Contributed Perl Documentation Math(3) NAME
PDL::Math - extended mathematical operations and special functions SYNOPSIS
use PDL::Math; use PDL::Graphics::TriD; imag3d [SURF2D,bessj0(rvals(zeroes(50,50))/2)]; DESCRIPTION
This module extends PDL with more advanced mathematical functions than provided by standard Perl. All the functions have one input pdl, and one output, unless otherwise stated. Many of the functions are linked from the system maths library or the Cephes maths library (determined when PDL is compiled); a few are implemented entirely in PDL. FUNCTIONS
acos Signature: (a(); [o]b()) The usual trigonometric function. Works inplace. acos does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. asin Signature: (a(); [o]b()) The usual trigonometric function. Works inplace. asin does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. atan Signature: (a(); [o]b()) The usual trigonometric function. Works inplace. atan does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. cosh Signature: (a(); [o]b()) The standard hyperbolic function. Works inplace. cosh does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. sinh Signature: (a(); [o]b()) The standard hyperbolic function. Works inplace. sinh does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. tan Signature: (a(); [o]b()) The usual trigonometric function. Works inplace. tan does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. tanh Signature: (a(); [o]b()) The standard hyperbolic function. Works inplace. tanh does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. ceil Signature: (a(); [o]b()) Round to integral values in floating-point format. Works inplace. ceil does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. floor Signature: (a(); [o]b()) Round to integral values in floating-point format. Works inplace. floor does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. rint Signature: (a(); [o]b()) Round to integral values in floating-point format. Works inplace. rint does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. pow Signature: (a(); b(); [o]c()) Synonym for `**'. Works inplace. pow does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. acosh Signature: (a(); [o]b()) The standard hyperbolic function. Works inplace. acosh does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. asinh Signature: (a(); [o]b()) The standard hyperbolic function. Works inplace. asinh does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. atanh Signature: (a(); [o]b()) The standard hyperbolic function. Works inplace. atanh does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. erf Signature: (a(); [o]b()) The error function. Works inplace. erf does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. erfc Signature: (a(); [o]b()) The complement of the error function. Works inplace. erfc does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. bessj0 Signature: (a(); [o]b()) The standard Bessel function. Works inplace. bessj0 does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. bessj1 Signature: (a(); [o]b()) The standard Bessel function. Works inplace. bessj1 does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. bessy0 Signature: (a(); [o]b()) The standard Bessel function. Works inplace. bessy0 does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. bessy1 Signature: (a(); [o]b()) The standard Bessel function. Works inplace. bessy1 does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. bessjn Signature: (a(); int n(); [o]b()) The standard Bessel function. This has a second integer argument which gives the order of the function required. Works inplace. bessjn does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. bessyn Signature: (a(); int n(); [o]b()) The standard Bessel function. This has a second integer argument which gives the order of the function required. Works inplace. bessyn does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. lgamma Signature: (a(); [o]b(); int[o]s()) log gamma function This returns 2 piddles -- the first set gives the log(gamma) values, while the second set, of integer values, gives the sign of the gamma function. This is useful for determining factorials, amongst other things. lgamma does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. badmask Signature: (a(); b(); [o]c()) Clears all "infs" and "nans" in $a to the corresponding value in $b. badmask can be run with $a inplace: badmask($a->inplace,0); $a->inplace->badmask(0); If bad values are present, these are also cleared. isfinite Signature: (a(); int [o]mask()) Sets $mask true if $a is not a "NaN" or "inf" (either positive or negative). Works inplace. Bad values are treated as "NaN" or "inf". erfi Signature: (a(); [o]b()) The inverse of the error function. Works inplace. erfi does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. ndtri Signature: (a(); [o]b()) The value for which the area under the Gaussian probability density function (integrated from minus infinity) is equal to the argument (cf erfi). Works inplace. ndtri does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. polyroots Signature: (cr(n); ci(n); [o]rr(m); [o]ri(m)) Complex roots of a complex polynomial, given coefficients in order of decreasing powers. ($rr, $ri) = polyroots($cr, $ci); polyroots does not process bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles. BUGS
Hasn't been tested on all platforms to ensure Cephes versions are picked up automatically and used correctly. AUTHOR
Copyright (C) R.J.R. Williams 1997 (rjrw@ast.leeds.ac.uk), Karl Glazebrook (kgb@aaoepp.aao.gov.au) and Tuomas J. Lukka (Tuomas.Lukka@helsinki.fi). Portions (C) Craig DeForest 2002 (deforest@boulder.swri.edu). All rights reserved. There is no warranty. You are allowed to redistribute this software / documentation under certain conditions. For details, see the file COPYING in the PDL distribution. If this file is separated from the PDL distribution, the PDL copyright notice should be included in the file. perl v5.12.1 2010-07-05 Math(3)