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Function std.math.cos

Returns cosine of x. x is in radians.

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

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

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

Special Values
x cos(x) invalid?
NAN NAN yes
±∞ NAN yes

Bugs

Results are undefined if |x| >= 264.

Example

writeln(cos(0.0)); // 1.0
assert(cos(1.0).approxEqual(0.540));
assert(cos(3.0).approxEqual(-0.989));

Authors

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

License

Boost License 1.0.