pwtools.num.deriv_spl¶
- pwtools.num.deriv_spl(y, x=None, xnew=None, n=1, fullout=False, **splrep_kwargs)[source]¶
n-th derivative for 1d arrays of possibly nonuniformly sampled data. Returns matching x-axis for plotting. Splines are used.
- Parameters:
x (1d arrays of same length) – if x=None, then x=arange(len(y)) is used
y (1d arrays of same length) – if x=None, then x=arange(len(y)) is used
xnew ({None, 1d array)) – x-axis to evaluate the derivative, if None then xnew=x
n (int) – order of the derivative, can only be <= k
fullout (bool) – return xd, yd or just yd
splrep_kwargs (keyword args to scipy.interpolate.splrep, default: k=3, s=0)
- Returns:
if fullout – xd, yd
else – yd
xd (1d array, (len(x) or len(xnew),))
yd (1d array, (len(x) or len(xnew),)) – n-th derivative of y at points xd
Notes
xd is actually == x or xnew (if x is not None). xd can be returned to match the function signature of deriv_fd.