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
/interp/math.c
SEE ALSO
math-intro(2)
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