[AMG]: TIP 232 [http://tip.tcl.tk/232] creates the '''::tcl::mathfunc''' [namespace] which contains commands implementing the [[[expr]]] math functions.  The functions are documented in the '''mathfunc(n)''' man page [http://www.tcl.tk/man/tcl8.5/TclCmd/mathfunc.htm].  (Previous to TIP 232, the math functions were documented in '''expr(n)'''.)

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'''List of functions:'''

 Absolute value              abs    arg | Hypotenuse length             hypot  x y
 Arc cosine                  acos   arg | Coerce to word-sized integer  int    arg
 Arc sine                    asin   arg | Natural logarithm             log    arg
 Arc tangent                 atan   arg | Base-10 logarithm             log10  arg
 Four-quadrant arc tangent   atan2  y x | Greatest value                max    args
 Coerce to boolean           bool   arg | Least value                   min    args
 Round up to whole number    ceil   arg | Power                         pow    x y
 Cosine                      cos    arg | Random in range (0,1)         rand
 Hyberbolic cosine           cosh   arg | Round to whole number         round  arg
 Coerce to float             double arg | Sine                          sin    arg
 Coerce to integer           entier arg | Hyperbolic sine               sinh   arg
 Exponential                 exp    arg | Square root                   sqrt   arg
 Round down to whole number  floor  arg | Seed random number generator  srand  arg
 Remainder                   fmod   x y | Tangent                       tan    arg
 Coerce to 64-bit integer    wide   arg | Hyperbolic tangent            tanh   arg

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Thanks to TIP 232, you can create new functions without having to resort to '''Tcl_CreateMathFunc(3)''' [http://www.tcl.tk/man/tcl8.5/TclLib/CrtMathFnc.htm].  This makes it possible for pure Tcl scripts to extend [[[expr]]].  Also this makes it possible to rewrite or delete math functions, two things that were previously impossible even for extensions written in [C].  (I have written code that needed this functionality; I guess it's time to update it!)

This makes math function arguments much more flexible, just as flexible as those of Tcl [proc]s and [command]s.  One possibility worth noting is variadic numbers of arguments, a feature used by the shiny, new '''min()''' and '''max()''' functions.

One more neat trick is calling math functions without using [[[expr]]]; they're regular Tcl commands now.  Combine this with TIP 174 [Math Operators as Commands], and you can avoid using [[[expr]]] altogether, bypassing the problems discussed at [brace your expr-essions].

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[Category Command] |
[Category Syntax]
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