Publications by nashjc
Floating-point summation and the M1 processor
John C. Nash, Retired Professor, University of Ottawa While I have had little to do with Apple since the early 1980s when they abandoned several products in which a colleague and I had invested time, effort and money, I recently had to take note of the introduction of the M1 chip in some of their products. This was not a choice. I had made some upd...
6099 sym R (1205 sym/4 pcs)
Why optim() is out of date
Why optim() is out of date And perhaps you should be careful using it Once upon a time Once upon a time, there was a young Oxford D.Phil. graduate with a thesis on quantum mechanics who — by virtue of a mixup in identities — got hired as an Agricultural Economist. He was actually better qualified than the person he was mistaken for, especia...
11788 sym R (9854 sym/7 pcs) 4 img
Choosing which method to use for “optimizing” functions
A decision tree for function minimization What R calls “optimization” is more generally known as function minimization. The tools in the stats package function optim() are all essentially function mimizers, as are those in the package optimrx found at https://r-forge.r-project.org/projects/optimizer/. optimrx tries to make it easier f...
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Unifying packages to help users access R repositories
With over 11,000 packages in the main CRAN (Consolidated R Archive Network) collection, users of R face a challenge when looking for tools to carry out their statistical and computational tasks, especially in subject areas outside their main domain of expertise. Moreover, a lot of packages have similar or overlapping features. Some are, to be kin...
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Enlarging the eBook supply
There has been a campaign by members of the Canadian library community to ask international publishers to reduce prices to libraries for eBooks. If my experience in the scientific publishing arena is any guide, the publishers will continue to charge the maximum they can get until the marketplace — that is us — forces them to change or get o...
6491 sym
Making a package from base R files
John C. Nash, retired professor, Telfer School of Management, University of OttawaArkajyoti Bhattacharjee, Department of Mathematics and Statistics, Indian Institute of Technology, Kanpurbased on communications from Duncan Murdoch 11/06/2021, revised 19/01/2022 Background This article tries to explain an approach to developing alternative version...
9052 sym Python (2697 sym/8 pcs)