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Programming-Idioms

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  • Js

Idiom #204 Return fraction and exponent of a real number

Given a real number a, print the fractional part and the exponent of the internal representation of that number. For 3.14, this should print (approximately)

0.785 2

function frexp(a) {
    exponent = ( Math.floor(Math.log(a, 2)) + 1 )
    mantissa = ( a * Math.pow(2, -a) )

    return [ mantissa, exponent ]
}
#include <math.h>
#include <stdio.h>
  double d = 3.14;
  double res;
  int e;

  res = frexp(d, &e);
  printf("%f %d\n",res,e);

New implementation...
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tkoenig