nanderivative.m v2.1 (Jul 2009)

N-order derivative of vector data by interpolating nearby points, ignoring NaNs.

Description

This program estimates the N-order (1rst derivative by default) derivative of a vector data Y (or the columns of a matrix) by interpolating, using INTERP1, two nearby points at each argument point X and then calculating their slope. It ignores NaNs elements.

>> dYdX = nanderivative(Y,X);

The N-order, the proximity of the interpolating points and the interpolation method (default 'spline') are optional input arguments.

Any comment will be very appreciated. (check the screenshot for an example)

• Acknowledgements: This submission has inspired the following:; der.m v1.0 (Nov, 2009)
• MATLAB release: MATLAB 7.7 (R2008b)