arccos() function is the trigonometric inverse cosine function so that, if y = cos(x), then x = arccos(y). If you apply it to a NumPy array, it performs the function element-wise.
numpy.arccos(x, out=None, where=True, <optional keyword arguments>)
|x||array_like||x-coordinate on the unit circle. For real arguments, the domain is |
|out||ndarray, ||(Optional.) A location into which the result is stored. If provided, it must have a shape that the inputs broadcast to. If not provided or None, a freshly-allocated array is returned. A tuple (possible only as a keyword argument) must have length equal to the number of outputs.|
|where||array_like||(Optional.) This condition is broadcast over the input. At locations where the condition is |
|**kwargs||For other keyword-only arguments, see the ufunc docs.|
The following table shows the return value of the function:
|angle||ndarray||The angle of the ray intersecting the unit circle at the given x-coordinate in radians |
arccos is a multivalued function: for each x there are infinitely many numbers z such that cos(z) = x. The convention is to return the angle z whose real part lies in [0, pi].
For real-valued input data types,
arccos always returns real output. For each value that cannot be expressed as a real number or infinity, it yields
nan and sets the invalid floating point error flag.
For complex-valued input,
arccos is a complex analytic function that has branch cuts [-inf, -1] and [1, inf] and is continuous from above on the former and from below on the latter.
cos is also known as acos or cos^-1.
Let’s dive into some examples to show how the function is used in practice:
Any master coder has a “hands-on” mentality with a bias towards action. Try it yourself—play with the function in the following interactive code shell:
Exercise: Modify the linspace() function so that you plot the arccos from -100 to +100!
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