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Function std.math.operations.nextDown

Calculate the next smallest floating point value before x.

real nextDown (
  real x
) pure nothrow @nogc @safe;

double nextDown (
  double x
) pure nothrow @nogc @safe;

float nextDown (
  float x
) pure nothrow @nogc @safe;

Return the greatest number less than x that is representable as a real; thus, it gives the previous point on the IEEE number line.

Special Values
x nextDown(x)
±0.0 -real.min_normal*real.epsilon
-real.max -∞
-∞ -∞


writeln(nextDown(1.0 + real.epsilon)); // 1.0


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


Boost License 1.0.