Module « scipy.interpolate »

Fonction splder - module scipy.interpolate

Signature de la fonction splder

def splder(tck, n=1) 

Description

splder.__doc__

    Compute the spline representation of the derivative of a given spline

    Parameters
    ----------
    tck : BSpline instance or a tuple of (t, c, k)
        Spline whose derivative to compute
    n : int, optional
        Order of derivative to evaluate. Default: 1

    Returns
    -------
    `BSpline` instance or tuple
        Spline of order k2=k-n representing the derivative
        of the input spline.
        A tuple is returned iff the input argument `tck` is a tuple, otherwise
        a BSpline object is constructed and returned.

    Notes
    -----

    .. versionadded:: 0.13.0

    See Also
    --------
    splantider, splev, spalde
    BSpline

    Examples
    --------
    This can be used for finding maxima of a curve:

    >>> from scipy.interpolate import splrep, splder, sproot
    >>> x = np.linspace(0, 10, 70)
    >>> y = np.sin(x)
    >>> spl = splrep(x, y, k=4)

    Now, differentiate the spline and find the zeros of the
    derivative. (NB: `sproot` only works for order 3 splines, so we
    fit an order 4 spline):

    >>> dspl = splder(spl)
    >>> sproot(dspl) / np.pi
    array([ 0.50000001,  1.5       ,  2.49999998])

    This agrees well with roots :math:`\pi/2 + n\pi` of
    :math:`\cos(x) = \sin'(x)`.