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Function std.math.traits.copysign

R copysign(R, X) (
  R to,
  X from
) pure nothrow @nogc @trusted
if (isFloatingPoint!R && isFloatingPoint!X);

R copysign(R, X) (
  X to,
  R from
) pure nothrow @nogc @trusted
if (isIntegral!X && isFloatingPoint!R);


to the numeric value to use
from the sign value to use


a value composed of to with from's sign bit.


writeln(copysign(1.0, 1.0)); // 1.0
writeln(copysign(1.0, -0.0)); // -1.0
writeln(copysign(1UL, -1.0)); // -1.0
writeln(copysign(-1.0, -1.0)); // -1.0

writeln(copysign(real.infinity, -1.0)); // -real.infinity
assert(copysign(real.nan, 1.0) is real.nan);
assert(copysign(-real.nan, 1.0) is real.nan);
assert(copysign(real.nan, -1.0) is -real.nan);


Walter Bright, Don Clugston, Conversion of CEPHES math library to D by Iain Buclaw and David Nadlinger


Boost License 1.0.