[Rd] Fwd: Bug report: cbind with numeric and raw gives incorrect result

[Tierney, Luke]

Thanks for the report and patch. Fixed in R-devel and R_patched.

Best,

luke

On Tue, 25 Sep 2018, brodie gaslam via R-devel wrote:

>
>
> For what it's worth the following patch fixes that particular problem on my system.  I have not checked very carefully to make sure this does not cause other problems, but at a high level it seems to make sense.  In this particular part of the code I believe `mode` is taken to be the highest type of "column" encountered by `ctype` and based on conditionals it can (I think) be up to REALSXP here.  This leads to a `INTEGER(REALSXP)` call, which presumably messes up the underlying double bit representation.
>
> Again, I looked at this very quickly so I could be completely wrong, but I did at least build R with this patch and then no longer observed the odd behavior reported by mikefc.
>
> Index: src/main/bind.c
> ===================================================================
> --- src/main/bind.c    (revision 75340)
> +++ src/main/bind.c    (working copy)
> @@ -1381,11 +1381,16 @@
>              MOD_ITERATE1(idx, k, i, i1, {
>                  LOGICAL(result)[n++] = RAW(u)[i1] ? TRUE : FALSE;
>              });
> -            } else {
> +            } else if (mode == INTSXP) {
>              R_xlen_t i, i1;
>              MOD_ITERATE1(idx, k, i, i1, {
>                  INTEGER(result)[n++] = (unsigned char) RAW(u)[i1];
>              });
> +            } else {
> +            R_xlen_t i, i1;
> +            MOD_ITERATE1(idx, k, i, i1, {
> +                REAL(result)[n++] = (unsigned char) RAW(u)[i1];
> +            });
>              }
>          }
>          }
>
>
>
>
>
>
> On Tuesday, September 25, 2018, 7:58:31 AM EDT, mikefc <mikefc using coolbutuseless.com> wrote:
>
>
>
>
>
> Hi there,
>
> using cbind with a numeric and raw argument produces an incorrect result.
>
> I've posted some details below,
>
> kind regards,
> Mike.
>
>
>
> e.g.
>> cbind(0, as.raw(0))
>     [,1]          [,2]
> [1,]    0 6.950136e-310
>
>
>
> A longer example shows that the result is not a rounding error, is not
> consistent, and repeated applications get different results.
>
>> cbind(0, as.raw(1:10))
>               [,1]          [,2]
> [1,]  0.000000e+00  0.000000e+00
> [2,]  0.000000e+00  0.000000e+00
> [3,]  0.000000e+00  0.000000e+00
> [4,]  0.000000e+00  0.000000e+00
> [5,]  0.000000e+00  6.950135e-310
> [6,] 4.243992e-314  6.950135e-310
> [7,] 8.487983e-314  6.324040e-322
> [8,] 1.273197e-313  0.000000e+00
> [9,] 1.697597e-313 -4.343725e-311
> [10,] 2.121996e-313  1.812216e-308
>
>
> This bug occurs on
> * mac os (with R 3.5.1)
> * linux (with R 3.4.4)
> * Windows (with R 3.5.0)
>
>
>
>
> My Session Info
> R version 3.5.1 (2018-07-02)
> Platform: x86_64-apple-darwin15.6.0 (64-bit)
> Running under: macOS High Sierra 10.13.6
>
> Matrix products: default
> BLAS: /System/Library/Frameworks/Accelerate.framework/Versions/
> A/Frameworks/vecLib.framework/Versions/A/libBLAS.dylib
> LAPACK: /Library/Frameworks/R.framework/Versions/3.5/
> Resources/lib/libRlapack.dylib
>
> locale:
> [1] en_AU.UTF-8/en_AU.UTF-8/en_AU.UTF-8/C/en_AU.UTF-8/en_AU.UTF-8
>
> attached base packages:
> [1] stats    graphics  grDevices utils    datasets  methods  base
>
> other attached packages:
> [1] memoise_1.1.0  ggplot2_3.0.0  nonogramp_0.1.0 purrr_0.2.5
> dplyr_0.7.6
>
> loaded via a namespace (and not attached):
> [1] Rcpp_0.12.18    rstudioapi_0.7  bindr_0.1.1      magrittr_1.5
> tidyselect_0.2.4 munsell_0.5.0    colorspace_1.3-2 R6_2.2.2
> rlang_0.2.1.9000 stringr_1.3.1    plyr_1.8.4      tools_3.5.1
> grid_3.5.1
> [14] packrat_0.4.9-3  gtable_0.2.0    withr_2.1.2      digest_0.6.15
> lazyeval_0.2.1  assertthat_0.2.0 tibble_1.4.2    crayon_1.3.4
> bindrcpp_0.2.2  pryr_0.1.4      codetools_0.2-15 glue_1.3.0
> labeling_0.3
> [27] stringi_1.2.4    compiler_3.5.1  pillar_1.3.0    scales_0.5.0
> pkgconfig_2.0.1
>
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>
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-- 
Luke Tierney
Ralph E. Wareham Professor of Mathematical Sciences
University of Iowa                  Phone:             319-335-3386
Department of Statistics and        Fax:               319-335-3017
    Actuarial Science
241 Schaeffer Hall                  email:   luke-tierney using uiowa.edu
Iowa City, IA 52242                 WWW:  http://www.stat.uiowa.edu