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diff --git a/doc/mathfunc.n b/doc/mathfunc.n new file mode 100644 index 0000000..a84c095 --- /dev/null +++ b/doc/mathfunc.n @@ -0,0 +1,273 @@ +'\" +'\" Copyright (c) 1993 The Regents of the University of California. +'\" Copyright (c) 1994-2000 Sun Microsystems, Inc. +'\" Copyright (c) 2005 by Kevin B. Kenny <kennykb@acm.org>. All rights reserved +'\" +'\" See the file "license.terms" for information on usage and redistribution +'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. +'\" +'\" RCS: @(#) $Id: mathfunc.n,v 1.21 2007/12/13 15:22:32 dgp Exp $ +'\" +.so man.macros +.TH mathfunc n 8.5 Tcl "Tcl Mathematical Functions" +.BS +'\" Note: do not modify the .SH NAME line immediately below! +.SH NAME +mathfunc \- Mathematical functions for Tcl expressions +.SH SYNOPSIS +package require \fBTcl 8.5\fR +.sp +\fB::tcl::mathfunc::abs\fR \fIarg\fR +.br +\fB::tcl::mathfunc::acos\fR \fIarg\fR +.br +\fB::tcl::mathfunc::asin\fR \fIarg\fR +.br +\fB::tcl::mathfunc::atan\fR \fIarg\fR +.br +\fB::tcl::mathfunc::atan2\fR \fIy\fR \fIx\fR +.br +\fB::tcl::mathfunc::bool\fR \fIarg\fR +.br +\fB::tcl::mathfunc::ceil\fR \fIarg\fR +.br +\fB::tcl::mathfunc::cos\fR \fIarg\fR +.br +\fB::tcl::mathfunc::cosh\fR \fIarg\fR +.br +\fB::tcl::mathfunc::double\fR \fIarg\fR +.br +.VS 8.5 +\fB::tcl::mathfunc::entier\fR \fIarg\fR +.br +.VE 8.5 +\fB::tcl::mathfunc::exp\fR \fIarg\fR +.br +\fB::tcl::mathfunc::floor\fR \fIarg\fR +.br +\fB::tcl::mathfunc::fmod\fR \fIx\fR \fIy\fR +.br +\fB::tcl::mathfunc::hypot\fR \fIx\fR \fIy\fR +.br +\fB::tcl::mathfunc::int\fR \fIarg\fR +.br +\fB::tcl::mathfunc::isqrt\fR \fIarg\fR +.br +\fB::tcl::mathfunc::log\fR \fIarg\fR +.br +\fB::tcl::mathfunc::log10\fR \fIarg\fR +.br +\fB::tcl::mathfunc::max\fR \fIarg\fR ?\fIarg\fR ...? +.br +\fB::tcl::mathfunc::min\fR \fIarg\fR ?\fIarg\fR ...? +.br +\fB::tcl::mathfunc::pow\fR \fIx\fR \fIy\fR +.br +\fB::tcl::mathfunc::rand\fR +.br +\fB::tcl::mathfunc::round\fR \fIarg\fR +.br +\fB::tcl::mathfunc::sin\fR \fIarg\fR +.br +\fB::tcl::mathfunc::sinh\fR \fIarg\fR +.br +\fB::tcl::mathfunc::sqrt\fR \fIarg\fR +.br +\fB::tcl::mathfunc::srand\fR \fIarg\fR +.br +\fB::tcl::mathfunc::tan\fR \fIarg\fR +.br +\fB::tcl::mathfunc::tanh\fR \fIarg\fR +.br +\fB::tcl::mathfunc::wide\fR \fIarg\fR +.sp +.BE +.SH "DESCRIPTION" +.PP +The \fBexpr\fR command handles mathematical functions of the form +\fBsin($x)\fR or \fBatan2($y,$x)\fR by converting them to calls of the +form \fB[tcl::mathfunc::sin [expr {$x}]]\fR or +\fB[tcl::mathfunc::atan2 [expr {$y}] [expr {$x}]]\fR. +A number of math functions are available by default within the +namespace \fB::tcl::mathfunc\fR; these functions are also available +for code apart from \fBexpr\fR, by invoking the given commands +directly. +.PP +Tcl supports the following mathematical functions in expressions, all +of which work solely with floating-point numbers unless otherwise noted: +.DS +.ta 3c 6c 9c +\fBabs\fR \fBacos\fR \fBasin\fR \fBatan\fR +\fBatan2\fR \fBbool\fR \fBceil\fR \fBcos\fR +\fBcosh\fR \fBdouble\fR \fBentier\fR \fBexp\fR +\fBfloor\fR \fBfmod\fR \fBhypot\fR \fBint\fR +\fBisqrt\fR \fBlog\fR \fBlog10\fR \fBmax\fR +\fBmin\fR \fBpow\fR \fBrand\fR \fBround\fR +\fBsin\fR \fBsinh\fR \fBsqrt\fR \fBsrand\fR +\fBtan\fR \fBtanh\fR \fBwide\fR +.DE +.PP +In addition to these predefined functions, applications may +define additional functions by using \fBproc\fR (or any other method, +such as \fBinterp alias\fR or \fBTcl_CreateObjCommand\fR) to define +new commands in the \fBtcl::mathfunc\fR namespace. In addition, an +obsolete interface named \fBTcl_CreateMathFunc\fR() is available to +extensions that are written in C. The latter interface is not recommended +for new implementations. +.SS "DETAILED DEFINITIONS" +.TP +\fBabs \fIarg\fR +Returns the absolute value of \fIarg\fR. \fIArg\fR may be either +integer or floating-point, and the result is returned in the same form. +.TP +\fBacos \fIarg\fR +Returns the arc cosine of \fIarg\fR, in the range [\fI0\fR,\fIpi\fR] +radians. \fIArg\fR should be in the range [\fI\-1\fR,\fI1\fR]. +.TP +\fBasin \fIarg\fR +Returns the arc sine of \fIarg\fR, in the range [\fI\-pi/2\fR,\fIpi/2\fR] +radians. \fIArg\fR should be in the range [\fI\-1\fR,\fI1\fR]. +.TP +\fBatan \fIarg\fR +Returns the arc tangent of \fIarg\fR, in the range [\fI\-pi/2\fR,\fIpi/2\fR] +radians. +.TP +\fBatan2 \fIy x\fR +Returns the arc tangent of \fIy\fR/\fIx\fR, in the range [\fI\-pi\fR,\fIpi\fR] +radians. \fIx\fR and \fIy\fR cannot both be 0. If \fIx\fR is greater +than \fI0\fR, this is equivalent to +.QW "\fBatan \fR[\fBexpr\fR {\fIy\fB/\fIx\fR}]" . +.TP +\fBbool \fIarg\fR +Accepts any numeric value, or any string acceptable to +\fBstring is boolean\fR, and returns the corresponding +boolean value \fB0\fR or \fB1\fR. Non-zero numbers are true. +Other numbers are false. Non-numeric strings produce boolean value in +agreement with \fBstring is true\fR and \fBstring is false\fR. +.TP +\fBceil \fIarg\fR +Returns the smallest integral floating-point value (i.e. with a zero +fractional part) not less than \fIarg\fR. The argument may be any +numeric value. +.TP +\fBcos \fIarg\fR +Returns the cosine of \fIarg\fR, measured in radians. +.TP +\fBcosh \fIarg\fR +Returns the hyperbolic cosine of \fIarg\fR. If the result would cause +an overflow, an error is returned. +.TP +\fBdouble \fIarg\fR +The argument may be any numeric value, +If \fIarg\fR is a floating-point value, returns \fIarg\fR, otherwise converts +\fIarg\fR to floating-point and returns the converted value. May return +\fBInf\fR or \fB\-Inf\fR when the argument is a numeric value that exceeds +the floating-point range. +.TP +\fBentier \fIarg\fR +.VS 8.5 +The argument may be any numeric value. The integer part of \fIarg\fR +is determined and returned. The integer range returned by this function +is unlimited, unlike \fBint\fR and \fBwide\fR which +truncate their range to fit in particular storage widths. +.VE 8.5 +.TP +\fBexp \fIarg\fR +Returns the exponential of \fIarg\fR, defined as \fIe\fR**\fIarg\fR. +If the result would cause an overflow, an error is returned. +.TP +\fBfloor \fIarg\fR +Returns the largest integral floating-point value (i.e. with a zero +fractional part) not greater than \fIarg\fR. The argument may be +any numeric value. +.TP +\fBfmod \fIx y\fR +Returns the floating-point remainder of the division of \fIx\fR by +\fIy\fR. If \fIy\fR is 0, an error is returned. +.TP +\fBhypot \fIx y\fR +Computes the length of the hypotenuse of a right-angled triangle +.QW "\fBsqrt\fR [\fBexpr\fR {\fIx\fB*\fIx\fB+\fIy\fB*\fIy\fR}]". +.TP +\fBint \fIarg\fR +The argument may be any numeric value. The integer part of \fIarg\fR +is determined, and then the low order bits of that integer value up +to the machine word size are returned as an integer value. For reference, +the number of bytes in the machine word are stored in +\fBtcl_platform(wordSize)\fR. +.TP +\fBisqrt \fIarg\fR +Computes the integer part of the square root of \fIarg\fR. \fIArg\fR must be +a positive value, either an integer or a floating point number. +Unlike \fBsqrt\fR, which is limited to the precision of a floating point +number, \fIisqrt\fR will return a result of arbitrary precision. +.TP +\fBlog \fIarg\fR +Returns the natural logarithm of \fIarg\fR. \fIArg\fR must be a +positive value. +.TP +\fBlog10 \fIarg\fR +Returns the base 10 logarithm of \fIarg\fR. \fIArg\fR must be a +positive value. +.TP +\fBmax \fIarg\fB \fI...\fR +Accepts one or more numeric arguments. Returns the one argument +with the greatest value. +.TP +\fBmin \fIarg\fB \fI...\fR +Accepts one or more numeric arguments. Returns the one argument +with the least value. +.TP +\fBpow \fIx y\fR +Computes the value of \fIx\fR raised to the power \fIy\fR. If \fIx\fR +is negative, \fIy\fR must be an integer value. +.TP +\fBrand\fR +Returns a pseudo-random floating-point value in the range (\fI0\fR,\fI1\fR). +The generator algorithm is a simple linear congruential generator that +is not cryptographically secure. Each result from \fBrand\fR completely +determines all future results from subsequent calls to \fBrand\fR, so +\fBrand\fR should not be used to generate a sequence of secrets, such as +one-time passwords. The seed of the generator is initialized from the +internal clock of the machine or may be set with the \fBsrand\fR function. +.TP +\fBround \fIarg\fR +If \fIarg\fR is an integer value, returns \fIarg\fR, otherwise converts +\fIarg\fR to integer by rounding and returns the converted value. +.TP +\fBsin \fIarg\fR +Returns the sine of \fIarg\fR, measured in radians. +.TP +\fBsinh \fIarg\fR +Returns the hyperbolic sine of \fIarg\fR. If the result would cause +an overflow, an error is returned. +.TP +\fBsqrt \fIarg\fR +The argument may be any non-negative numeric value. Returns a floating-point +value that is the square root of \fIarg\fR. May return \fBInf\fR when the +argument is a numeric value that exceeds the square of the maximum value of +the floating-point range. +.TP +\fBsrand \fIarg\fR +The \fIarg\fR, which must be an integer, is used to reset the seed for +the random number generator of \fBrand\fR. Returns the first random +number (see \fBrand\fR) from that seed. Each interpreter has its own seed. +.TP +\fBtan \fIarg\fR +Returns the tangent of \fIarg\fR, measured in radians. +.TP +\fBtanh \fIarg\fR +Returns the hyperbolic tangent of \fIarg\fR. +.TP +\fBwide \fIarg\fR +The argument may be any numeric value. The integer part of \fIarg\fR +is determined, and then the low order 64 bits of that integer value +are returned as an integer value. +.SH "SEE ALSO" +expr(n), mathop(n), namespace(n) +.SH "COPYRIGHT" +.nf +Copyright (c) 1993 The Regents of the University of California. +Copyright (c) 1994-2000 Sun Microsystems Incorporated. +Copyright (c) 2005, 2006 by Kevin B. Kenny <kennykb@acm.org>. +.fi |