CrossWorks for ARM User Guide

ldexpSynopsis#include double ldexp(double x, int exp);Description ldexp multiplies a floating-point number by an integral power of 2.ldexp returns x * 2^exp.Fast math librarybehaviorIEC 60559 mathlibrary behaviorPortabilityIf the result overflows, errno is set to ERANGE and ldexp returns HUGE_VAL.If x is Infinity or NaN, ldexp returns x.If the result overflows, ldexp returns Infinity.ldexp conforms to ISO/IEC 9899:1990 (C90) and ISO/IEC 9899:1999 (C99).ldexpfSynopsis#include float ldexpf(float x, int exp);Description ldexpf multiplies a floating-point number by an integral power of 2.ldexpf returns x * 2^exp.Fast math librarybehaviorIEC 60559 mathlibrary behaviorPortabilityIf the result overflows, errno is set to ERANGE and ldexpf returns HUGE_VALF.If x is Infinity or NaN, ldexpf returns x.If the result overflows, ldexpf returns Infinity.ldexpf conforms to ISO/IEC 9899:1990 (C90) and ISO/IEC 9899:1999 (C99).logSynopsis#include double log(double x);Description log computes the base-e logarithm of x.Fast math librarybehaviorIEC 60559 mathlibrary behaviorPortabilityIf x = 0, errno is set to ERANGE and log returns -HUGE_VAL.If x < 0, errno is set to EDOM and log returns -HUGE_VAL.If x < 0 or x = -Infinity, log returns NaN with signal.If x = 0, log returns -Infinity with signal.If x = Infinity, log returns Infinity.If x = NaN, log returns x with no signal.log conforms to ISO/IEC 9899:1990 (C90) and ISO/IEC 9899:1999 (C99).268 Chapter 28 Standard C Library Reference