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class method

Math.atan

Math.atan(x) → Float

static VALUE
math_atan(VALUE unused_obj, VALUE x)
{
    return DBL2NUM(atan(Get_Double(x)));
}

Computes the arc tangent of x. Returns -PI/2..PI/2.

Domain: (-INFINITY, INFINITY)

Codomain: (-PI/2, PI/2)

Example

Math.atan(0) #=> 0.0

See also .asinh .atan2 .asin .atanh also in 4.1 · 4.0 · 3.4 · 3.3 · 3.2 · 3.0