slmsuite.misc.fitfunctions.cos

cos(x, b, a, c, k=1)

For fitting an offset sinusoid.

\[y(x) = c + \frac{a}{2} \left[1+\cos(kx+b) \right].\]

Parameters

• x (numpy.ndarray) – Phase in radians.

• b (float) – Phase offset.

• a (float) – Peak amplitude.

• c (float) – Amplitude offset.

• k (float) – Phase scale factor. Default is 1.

Returns

y – Cosine fit evaluated at all x.

Return type

numpy.ndarray