#67 Slice does not like whitespace
Hi,
a minor bug but annoying to debug ... took me about an hour to find what's wrong ...
PDL (latest build) produced the following error :
print $cab2->dummy(-1,$$p{ky})->info;
$cabc2->info: PDL: Double D [128,6,1,2,8]
$$p{ky} is ' 128 ' - single quotes are only to show the padding white space.
Invalid slice str ',,,,,* 128 ': ' 128 ' at Basic/Core/Core.pm.PL (i.e. PDL::Core.pm) line 396
PDL::Core::barf('Invalid slice str \',,,,,* 128 \': \' 128 \'') called at Basic/Core/Core.pm.PL (i.e. PDL::Core.pm) line 1592
PDL::dummy('PDL=SCALAR(0x1df98c0)', -1, ' 128 ') called at /home/ingo/perl/reco_utils.pm line 84
reco_utils::epi('PDL=SCALAR(0x1df9998)', 'PDL=SCALAR(0x1df98a8)', 'PDL=SCALAR(0x1df9d28)', 'HASH(0x1dc9830)') called at /home/ingo/perl/reco_utils.pm line 364
reco_utils::fou('PDL=SCALAR(0x1df9bf0)', 'HASH(0x1dc9830)', 'PDL=SCALAR(0x1df9f38)') called at /home/ingo/perl/offline-reco.pl line 263
at Basic/Core/Core.pm.PL (i.e. PDL::Core.pm) line 396
PDL::Core::barf('Invalid slice str \',,,,,* 128 \': \' 128 \'') called at Basic/Core/Core.pm.PL (i.e. PDL::Core.pm) line 1592
PDL::dummy('PDL=SCALAR(0x1df98c0)', -1, ' 128 ') called at /home/ingo/perl/reco_utils.pm line 84
reco_utils::epi('PDL=SCALAR(0x1df9998)', 'PDL=SCALAR(0x1df98a8)', 'PDL=SCALAR(0x1df9d28)', 'HASH(0x1dc9830)') called at /home/ingo/perl/reco_utils.pm line 364
reco_utils::fou('PDL=SCALAR(0x1df9bf0)', 'HASH(0x1dc9830)', 'PDL=SCALAR(0x1df9f38)') called at /home/ingo/perl/offline-reco.pl line 263
Died at /home/ingo/perl/offline-reco.pl line 351.
The following works:
print $cab2->dummy(-1,($$p{ky})*1.)->info;
This effects the slice method. The definition starts on line 1642 of Basic/Slices/slices.pd. Whitespace should be handled somewhere in the vicinity of line 1800, or by preprocessing and building our own local string that has no whitespace.
The current behavior is as documented. Please use niceslice
to work around or use values that look like '*#'. The slice call
might be able to be more permissive in this case but the mod
will not be available for PDL-2.4.10.
I've marked this as a feature request to improve PDL ease-of-use.
Moving to Feature Request tracker since the existing functionality works as documented.
Since the problem here seems to be more the fact that slice() was called behind the scenes by dummy() with a generated string rather than the current slice syntax, I've modified dummy() to convert $size to a number before constructing the "*$size" argument for the underlying slice() call. This should avoid this hard-to-detect error.
The unified slice support in the coming PDL-2.007 release is no longer sensitive to whitespace in the slice string.