MATLAB: Is there a function in Matlab that is similar to “cumtrapz” but uses a more accurate method of array integration (such as Simpson’s rule)

array integrationcummulative integration

Is there a function in Matlab that is similar to "cumtrapz" but uses a more accurate method of array integration (such as Simpson's rule)? (i.e., to integrate a nonanalytic function (represented by an array))

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You COULD use a spline interpolant, then integrating the spline. That would be a higher order integration. (Pchip MAY be a better choice than spline, although spline will be theoretically a higher order as an integration tool here.)

Or you could use a Simpsons rule. Note that it is easy to think you are doing a better job, because the integration rule is of a "higher" polynomial order. In fact, it is trivial to give you a set of points that will cause a simple high order integration to fail miserably.

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MATLAB: Vector integration; is this the most correct and/or accurate calculation

This is a slightly complex question.

Is it the correct use of trapz? Of course.

Is it the most accurate possible way to integrate a data series? It is just trapezoidal rule, for god sakes. Trapezoidal rule is a good choice if there is any noise at all in your data. Higher order rules tend to amplify any noise, whereas trapezoidal rule is about as good as you can get in terms of not amplifying any noise, so it can be a minimum variance estimator, unless you need to use smoothing.

However, if your series represents a very smooth kernel, then trapezoidal rule may not be the best choice. You would be better off using a higher order rule. Perhaps a higher order Newton Cotes rule (Simpson's rule is the simple example that you might have heard of.) Or you could interpolate the points using a spline, then integrate the spline.

MATLAB: How to evaluate neural network tool (such as, BP and MLP) in matlab.

If this is a classification problem, search words are

 patternet    (Current function for classification and pattern recognition)
 newpr       ( Obsolete function if you do not have patternnet)
 Try the classification examples at
 help nndatasets

If you have problems with any of the examples post comments and error messages

Hope this helps.

Thank you for formally accepting my answer

Greg

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MATLAB: Vector integration; is this the most correct and/or accurate calculation

MATLAB: How to evaluate neural network tool (such as, BP and MLP) in matlab.

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