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Showing posts from March, 2013

Evaluation of non-linear expressions using Excel

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NAG provides VB headers for all the routines in the library allowing them to be called easily from Microsoft Excel given a little knowledge of Visual Basic. Along with the headers, some Excel examples are distributed with the product. You may also find demo worksheets for a variety of routines on the NAG web site.

Combining the ease of use of Excel and the power of NAG routines is a great way of creating simple, flexible interfaces for solving difficult problems. Typically you write VBA code to handle the reading and writing of data to the Excel worksheet and the passing of parameters to the NAG routines. Once this VBA code has been written the problem parameters can be easily changed and tweaked from the worksheet without having to alter any code again.
Routines which take only simple parameters such as scalar values, vectors and matrices can have all their arguments input via the Excel worksheet however for routines that require non-linear expression such as those routines with cal…

3 Years Later

Do you remember those episodes of Friends that consisted entirely of flashbacks - presumably the cast were too busy with other duties that week so couldn't film, or the writers too busy to think up a real story ...

The NAG Blog has been running for just over 3 years now. In that time we have had 118 posts on a wide variety of numerical computing topics including HPC, .NET, customer engagement, GPUs, optimization, and much more.

The most popular posts (pageviews) have often been the most technical ones - including:
ParaView, VTK files and endiannessStoring banded matrices for speedOptimization, statistics, big data and business analytics
On the HPC theme, there have been posts discussing factors of 1000x in performance, describing supercomputing to friends, family and politicians, and the relationship between supercomputers and ice cubes.
I hope you have found our blog to be a nice mix of useful content, occasional fun, and topical thoughts. Do you have a favourite NAG Blog post - o…