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/*
* Copyright 2016 The Emscripten Authors. All rights reserved.
* Emscripten is available under two separate licenses, the MIT license and the
* University of Illinois/NCSA Open Source License. Both these licenses can be
* found in the LICENSE file.
*/
#include <stdio.h>
#include <math.h>
#include <assert.h>
static const double tol = 1e-16;
void test_value(double value) {
int exponent;
double x = frexp(value, &exponent);
double expected = x * pow(2.0, exponent);
printf("%f=%f*2^%d\n", value, x, exponent);
assert(fabs(expected - value) < tol);
assert(x == 0 || (fabs(x) >= 5e-1 && fabs(x) < 1)); // x has a magnitude in
// the interval [1/2, 1)
}
int main() {
test_value(0);
test_value(100.1);
test_value(-100.1);
test_value(.5);
test_value(-.5);
test_value(1 - 1e-16);
test_value(-(1 - 1e-16));
return 0;
}
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