numpy.emath.arccos#
- emath.arccos(x)[source]#
- Compute the inverse cosine of x. - Return the “principal value” (for a description of this, see - numpy.arccos) of the inverse cosine of x. For real x such that abs(x) <= 1, this is a real number in the closed interval \([0, \pi]\). Otherwise, the complex principle value is returned.- Parameters:
- xarray_like or scalar
- The value(s) whose arccos is (are) required. 
 
- Returns:
- outndarray or scalar
- The inverse cosine(s) of the x value(s). If x was a scalar, so is out, otherwise an array object is returned. 
 
 - See also - Notes - For an arccos() that returns - NANwhen real x is not in the interval- [-1,1], use- numpy.arccos.- Examples - >>> import numpy as np >>> np.set_printoptions(precision=4) - >>> np.emath.arccos(1) # a scalar is returned 0.0 - >>> np.emath.arccos([1,2]) array([0.-0.j , 0.-1.317j])