Fri, 05 Feb 2021

RcppFastFloat 0.0.1: New Package, Already on CRAN

A new package, once again based on wonderful library by Daniel Lemire, is now on CRAN in its initial version 0.0.1. Daniel, in a recent arXiv paper shows that one can convert character representations of ‘numbers’ into floating point at rates at or exceeding one gigabyte per second. His tests show a fourfold gain over library functions such as strtod.

We put a simply package together showing use of the example parser, and containing a simple ‘all-in’ comparison benchmark (where we time the function call overhead as well) and get roughly 3x. See the repo for details; we are borring the table and figure here:

> source("comparison.R")
Unit: milliseconds
      expr      min       lq     mean   median       uq      max neval cld
     scanf 218.8936 224.1223 238.5650 227.1901 229.9116 1343.433   100   c
      atof 124.8087 127.3274 129.4104 128.5858 130.9138  146.334   100  b 
    strtod 124.5705 127.2157 129.1238 129.1042 130.7504  137.143   100  b 
      stod 127.1751 129.7343 131.7339 131.4854 133.1425  147.763   100  b 
 fastfloat  40.6219  41.3042  42.5729  42.3209  43.1738   57.788   100 a  

Or in chart form:

Not much to say yet for the initial release:

Changes in version 0.0.1 (2021-01-31)

  • Initial version and CRAN upload

While the package was waiting to be added to CRAN, Brendan already added a potential as.double() replacement which will be in the next version.

If you like this or other open-source work I do, you can now sponsor me at GitHub.

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. Please report excessive re-aggregation in third-party for-profit settings.

/code/rcpp | permanent link