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discard """
targets: "js c c++"
output: '''ok'''
"""
import math
import strformat
const manualTest = false
proc frexp_test(lo, hi, step: float64) =
var exp: int
var frac: float64
var eps = 1e-15.float64
var x:float64 = lo
while x <= hi:
frac = frexp(x.float, exp)
let rslt = pow(2.0, float(exp)) * frac
doAssert(abs(rslt - x) < eps)
when manualTest:
echo %("x: {x:10.3f} exp: {exp:4d} frac: {frac:24.20f} check: {$(abs(rslt - x) < eps):-5s} {rslt: 9.3f}")
x += step
when manualTest:
var exp: int
var frac: float64
for flval in [1.7976931348623157e+308, -1.7976931348623157e+308, # max, min float64
3.4028234663852886e+38, -3.4028234663852886e+38, # max, min float32
4.9406564584124654e-324, -4.9406564584124654e-324, # smallest/largest positive/negative float64
1.4012984643248171e-45, -1.4012984643248171e-45, # smallest/largest positive/negative float32
2.2250738585072014e-308, 1.1754943508222875e-38]: # smallest normal float64/float32
frac = frexp(flval, exp)
echo fmt("{flval:25.16e}, {exp: 6d}, {frac: .20f} {frac * pow(2.0, float(exp)): .20e}")
frexp_test(-1000.0, 1000.0, 0.0125)
else:
frexp_test(-1000000.0, 1000000.0, 0.125)
echo "ok"
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