MATH-ELEM(2)                                         MATH-ELEM(2)

     NAME
          Math: cbrt, sqrt, pow, pow10, hypot, exp, expm1, log, log10,
          log1p, cos, cosh, sin, sinh, tan, tanh, acos, asin, acosh,
          asinh, atan, atanh, atan2, lgamma, erf, erfc, j0, j1, y0,
          y1, jn, yn - elementary functions of applied mathematics

     SYNOPSIS
          include "math.m";
          math := load Math Math->PATH;

          cbrt, sqrt: fn(x: real): real;
          pow: fn(x, y: real): real;
          pow10: fn(p: int): real;
          hypot: fn(x, y: real): real;
          exp, expm1, log, log10, log1p: fn(x: real): real;

          cos, cosh, sin, sinh, tan, tanh: fn(x: real): real;
          acos, asin, acosh, asinh, atan, atanh: fn(x: real): real;
          atan2: fn(y, x: real) of real;

          lgamma: fn(x: real): (int,real);
          erf, erfc: fn(x: real): real;
          j0, j1, y0, y1: fn(x: real): real;
          jn, yn: fn(n: int, x: real): real;

     DESCRIPTION
          These routines implement the basic elementary functions of
          applied mathematics.

          Sqrt(x) computes the square root of x, cbrt(x) the cube
          root.  Pow(x,y) computes x raised to the exponent y; pow10
          raises 10 to the integer power n. Hypot(x,y) computes
          sqrt(x*x+y*y).

          Exp(x) returns the exponential function of x, and expm1(x)
          is exp(x)-1.

          Log(x) returns the natural logarithm of x, while log10(x)
          returns the logarithm base 10 and log1p(x) returns the loga-
          rithm of 1+x.

          The trigonometric functions use radians.  The ranges of the
          inverse functions are: acos in [0,J]; asin in [-J/2,J/2];
          atan in [-J/2,J/2]; and atan2(y,x) = arctan(y/x) in [-J,J];

          The gamma function is implemented by lgamma(x); the tuple it
          returns, say (s,lg), encodes the gamma function by G(x) =
          s*exp(lg).

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     MATH-ELEM(2)                                         MATH-ELEM(2)

          The hyperbolic trigonometric functions sinh etc. behave as
          expected.  Erf is the error function and erfc(x) is
          1-erf(x).

          The Bessel functions are computed by j0, j1, jn, y0, y1, and
          yn.

     SOURCE
          /libinterp/math.c

     SEE ALSO
          math-intro(2)

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