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Function std.math.traits.isSubnormal

Determines if x is subnormal.

bool isSubnormal(X) (
  X x
) pure nothrow @nogc @trusted;

Subnormals (also known as "denormal number"), have a 0 exponent and a 0 most significant mantissa bit.


x a floating point number.


true if x is a denormal number.


import std.meta : AliasSeq;

static foreach (T; AliasSeq!(float, double, real))
    T f;
    for (f = 1.0; !isSubnormal(f); f /= 2)
        assert(f != 0);


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


Boost License 1.0.