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Function std.math.log2

Calculates the base-2 logarithm of x: ⊂x

x log2(x) divide by 0? invalid? ±0.0 -∞ yes no <0.0 no yes +∞ +∞ no no

Prototype

real log2(
  real x
) pure nothrow @nogc @safe;

Example

// check if values are equal to 19 decimal digits of precision
assert(equalsDigit(log2(1024.0L), 10, 19));

Authors

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

License

Boost License 1.0.

Comments