cos

cos(x: array, /) → array

Calculates an implementation-dependent approximation to the cosine, having domain (-infinity, +infinity) and codomain [-1, +1], for each element x_i of the input array x. Each element x_i is assumed to be expressed in radians.

Special cases

For floating-point operands,

  • If x_i is NaN, the result is NaN.

  • If x_i is +0, the result is 1.

  • If x_i is -0, the result is 1.

  • If x_i is +infinity, the result is NaN.

  • If x_i is -infinity, the result is NaN.

Parameters:

x (array) – input array whose elements are each expressed in radians. Should have a floating-point data type.

Returns:

out (array) – an array containing the cosine of each element in x. The returned array must have a floating-point data type determined by Type Promotion Rules.