interp_spline_data


interp_spline_data, a MATLAB code which interactively creates a cubic spline interpolant to (x,y) data, using the 'not-a-knot' end conditions.

This function manages an interactive computation which accepts vectors xdata and ydata, constructs a cubic spline interpolant to the data, and returns values of the spline at 101 sample points.

The user enters the data vectors xdata and ydata.

The parameters can be supplied as named variables:

        xdata = [ 0, 0.25, 0.50, 1.0 ];
        ydata = [ 1, 0.75, 0,    2.0 ];
        [xp,yp] = interp_spline_data ( xdata, ydata );

The parameters can be supplied as two lists of numerical values and passed to the function:

        [xp,yp] = interp_spline_data ( [0,0.25,0.50,1.0], [1,0.75,0,2.0] );

The function can called with no arguments, and they will be requested.

        [xp,yp] = interp_spline_data();
        Enter xdata, like [1,1.5,2]: [0,0.25,0.50,1.0]
        Enter ydata, like [1,2.25,4]: [1,0.75,0,2.0]

Licensing:

The computer code and data files made available on this web page are distributed under the GNU LGPL license.

Languages:

interp_spline_data is available in a MATLAB version.

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Source Code:


Last revised on 01 August 2019.