diff options
author | Eric Andersen <andersen@codepoet.org> | 2001-05-10 00:40:28 +0000 |
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committer | Eric Andersen <andersen@codepoet.org> | 2001-05-10 00:40:28 +0000 |
commit | 1077fa4d772832f77a677ce7fb7c2d513b959e3f (patch) | |
tree | 579bee13fb0b58d2800206366ec2caecbb15f3fc /libm/float/coshf.c | |
parent | 22358dd7ce7bb49792204b698f01a6f69b9c8e08 (diff) |
uClibc now has a math library. muahahahaha!
-Erik
Diffstat (limited to 'libm/float/coshf.c')
-rw-r--r-- | libm/float/coshf.c | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/libm/float/coshf.c b/libm/float/coshf.c new file mode 100644 index 000000000..2b44fdeb3 --- /dev/null +++ b/libm/float/coshf.c @@ -0,0 +1,67 @@ +/* coshf.c + * + * Hyperbolic cosine + * + * + * + * SYNOPSIS: + * + * float x, y, coshf(); + * + * y = coshf( x ); + * + * + * + * DESCRIPTION: + * + * Returns hyperbolic cosine of argument in the range MINLOGF to + * MAXLOGF. + * + * cosh(x) = ( exp(x) + exp(-x) )/2. + * + * + * + * ACCURACY: + * + * Relative error: + * arithmetic domain # trials peak rms + * IEEE +-MAXLOGF 100000 1.2e-7 2.8e-8 + * + * + * ERROR MESSAGES: + * + * message condition value returned + * coshf overflow |x| > MAXLOGF MAXNUMF + * + * + */ + +/* cosh.c */ + +/* +Cephes Math Library Release 2.2: June, 1992 +Copyright 1985, 1987, 1992 by Stephen L. Moshier +Direct inquiries to 30 Frost Street, Cambridge, MA 02140 +*/ + +#include <math.h> +extern float MAXLOGF, MAXNUMF; + +float expf(float); + +float coshf(float xx) +{ +float x, y; + +x = xx; +if( x < 0 ) + x = -x; +if( x > MAXLOGF ) + { + mtherr( "coshf", OVERFLOW ); + return( MAXNUMF ); + } +y = expf(x); +y = y + 1.0/y; +return( 0.5*y ); +} |