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bundles / scipy 1.17.1 / scipy / interpolate / _fitpack_py / insert

function

scipy.interpolate._fitpack_py:insert

source: /scipy/interpolate/_fitpack_py.py :668

Signature

def   insert ( x ,  tck ,  m = 1 ,  per = 0 )

Summary

Insert knots into a B-spline.

Extended Summary

Given the knots and coefficients of a B-spline representation, create a new B-spline with a knot inserted m times at point x. This is a wrapper around the FORTRAN routine insert of FITPACK.

Parameters

x (u) : float

A knot value at which to insert a new knot. If tck was returned from splprep, then the parameter values, u should be given.

tck : a `BSpline` instance or a tuple

If tuple, then it is expected to be a tuple (t,c,k) containing the vector of knots, the B-spline coefficients, and the degree of the spline.

m : int, optional

The number of times to insert the given knot (its multiplicity). Default is 1.

per : int, optional

If non-zero, the input spline is considered periodic.

Returns

: BSpline instance or a tuple

A new B-spline with knots t, coefficients c, and degree k. t(k+1) <= x <= t(n-k), where k is the degree of the spline. In case of a periodic spline (per != 0) there must be either at least k interior knots t(j) satisfying t(k+1)<t(j)<=x or at least k interior knots t(j) satisfying x<=t(j)<t(n-k). A tuple is returned iff the input argument tck is a tuple, otherwise a BSpline object is constructed and returned.

Notes

Based on algorithms from [1] and [2].

Manipulating the tck-tuples directly is not recommended. In new code, prefer using the BSpline objects, in particular BSpline.insert_knot method.

Array API Standard Support

insert is not in-scope for support of Python Array API Standard compatible backends other than NumPy.

See dev-arrayapi for more information.

Examples

You can insert knots into a B-spline. 
from scipy.interpolate import splrep, insert
import numpy as np
x = np.linspace(0, 10, 5)
y = np.sin(x)
tck = splrep(x, y)
tck[0]
✓
A knot is inserted: 
tck_inserted = insert(3, tck)
tck_inserted[0]
✓
Some knots are inserted: 
tck_inserted2 = insert(8, tck, m=3)
tck_inserted2[0]
✓

See also

BSpline.insert_knot

Aliases

  • scipy.interpolate.insert

Referenced by

This package