I have a PDL (type double) of mixed values (both positive and negative). I want to round each entry towards zero.
So +1.2 becomes +1, +1.7 becomes +1, -1.2 becomes -1, and -1.7 becomes -1,
I thought of using int(), but it doesn't work on PDL types.
I can also use round(abs($x) - 0.5) * ($x <=> 0), but not sure how to use this logic on a PDL.
Pointers?
The documentation of the rint function in PDL::Math says:
If you want to round half-integers away from zero, try
floor(abs($x)+0.5)*($x<=>0).
Just change it slightly to make it work the way you want:
#!/usr/bin/perl
use warnings;
use strict;
use PDL;
my $pdl = 'PDL'->new(
[ 1, 1.3, 1.9, 2, 2.1, 2.7 ],
[ -1, -1.3, -1.9, -2, -2.1, -2.7 ]
);
$pdl = floor(abs($pdl)) * ($pdl <=> 0);
print $pdl;
Output:
[
[ 1 1 1 2 2 2]
[-1 -1 -1 -2 -2 -2]
]