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Sum benchmark

version 1.0.0.0 (2.41 KB) by Alain Barraud
Compute set of real values to be summed with an a priori known sum and specified condition number

585 Downloads

Updated 05 Mar 2009

No License

For a given n, a condition number cth and a value s, Sumbench.m computes a n-vector x with x(1)+...+x(n) = s exactly and whose the sum condition number is about cth within sharp bounds. The true condition number is also returned.
An option is given to return an x such that the exact sum is not exactly a floating point but whose value is described 2 floating point. In this case a third output argument v is a 2 vector such that s= v(1)+ v(2) with v(2)<eps*v(1) ( no overlap).
Sumbench calls another m file exactsum.m which can be used directly for personnal test purpose. This small routines computes the exact sum of any given n- vector. See the comments for details.

Cite As

Alain Barraud (2022). Sum benchmark (https://www.mathworks.com/matlabcentral/fileexchange/23198-sum-benchmark), MATLAB Central File Exchange. Retrieved .

MATLAB Release Compatibility
Created with R2007b
Compatible with any release
Platform Compatibility
Windows macOS Linux
Acknowledgements

Inspired: XSum

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