[R] More precision problems in testing with Intel compilers

[Samuelson, Frank*]

The Intel compiled version also fails the below test:

> ###------------ Very big and very small
> umach <- unlist(.Machine)[paste("double.x", c("min","max"), sep='')]
> xmin <- umach[1]
> xmax <- umach[2]
> tx <- unique(outer(-1:1,c(.1,1e-3,1e-7)))# 7 values  (out of 9)
> tx <- unique(sort(c(outer(umach,1+tx))))# 11 values  (out of 14)
> tx <- tx[is.finite(tx)] #-- all kept
> (txp <- tx[tx >= 1])#-- Positive exponent -- 4 values
[1] 1.617924e+308 1.795895e+308 1.797693e+308 1.797693e+308
> (txn <- tx[tx <        1])#-- Negative exponent -- 7 values
[1] 2.002566e-308 2.222849e-308 2.225074e-308 2.225074e-308 2.225074e-308
2.227299e-308 2.447581e-308


Does anyone really care about being correct to 1 unit of machine precision?
If you do, you have a bad algorithm.



-----Original Message-----
From: Samuelson, Frank* [mailto:FWS4 at cdrh.fda.gov] 
Sent: Thursday, August 19, 2004 12:11 PM
To: 'r-help at stat.math.ethz.ch '
Subject: [R] precision problems in testing with Intel compilers


I compiled the 1.9.1 src.rpm with the standard gnu tools and it works.
I tried compiling the 1.9.1 src.rpm with the Intel 8 C and FORTRAN
compilers and it bombs out during the testing phase:

    comparing 'd-p-q-r-tests.Rout' to './d-p-q-r-tests.Rout.save' ...267c267
    < df = 0.5[1] "Mean relative  difference: 5.001647e-10"
    ---
    > df = 0.5[1] TRUE
    make[3]: *** [d-p-q-r-tests.Rout] Error 1
    make[3]: Leaving directory `/usr/src/redhat/BUILD/R-1.9.1/tests'
    make[2]: *** [test-Specific] Error 2
    make[2]: Leaving directory `/usr/src/redhat/BUILD/R-1.9.1/tests'
    make[1]: *** [test-all-basics] Error 1
    make[1]: Leaving directory `/usr/src/redhat/BUILD/R-1.9.1/tests'
    make: *** [check-all] Error 2
    error: Bad exit status from /var/tmp/rpm-tmp.63044 (%build)
...