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class method

Math.cos

Math.cos(x) → Float

static VALUE
math_cos(VALUE unused_obj, VALUE x)
{
    return DBL2NUM(cos(Get_Double(x)));
}

Computes the cosine of x (expressed in radians). Returns a Float in the range -1.0..1.0.

Domain: (-INFINITY, INFINITY)

Codomain: [-1, 1]

Example

Math.cos(Math::PI) #=> -1.0

See also .cbrt .cosh .atanh .erf also in 4.1 · 4.0 · 3.4 · 3.3 · 3.2 · 3.0