github #5 : add a PDL::SV::uniqind() method

Changes

@@ -2,6 +2,7 @@ Revision history of Alt-Data-Frame-ButMore
 
 0.0052_01   TBD
     - Add a Data::Frame::drop_bad() method.
+    - Add a PDL::SV::uniqind() method.
     - Add a "faithfuld" example.
 
 0.0051      2019-06-01

lib/PDL/SV.pm

@@ -194,16 +194,30 @@ sub glue {
 
 BAD values are not considered unique and are ignored.
 
+=head2 uniqind()
+
+Return the indices of all uniq elements of a piddle.
+
 =cut
 
 sub uniq {
-    my $self  = shift;
+    my ($self) = @_;
     my $class = ref($self);
 
     my @uniq = List::AllUtils::uniq( grep { defined $_ }
           @{ $self->_effective_internal } );
-    my $new = $class->new( \@uniq );
-    return $new;
+    return $class->new( \@uniq );
+}
+
+## Please see file perltidy.ERR
+sub uniqind {
+    my ($self) = @_;
+
+    my $effective_internal = $self->_effective_internal;
+    my @uniqind = List::AllUtils::uniq_by { $effective_internal->[$_] }
+        grep { defined $effective_internal->[$_] }
+            ( 0 .. $#$effective_internal );
+    return pdl( \@uniqind );
 }
 
 =head2 sever

t/11-pdl_sv.t

@@ -47,8 +47,11 @@ subtest at => sub {
 };
 
 subtest uniq => sub {
-    my $p1 = PDL::SV->new( [qw(foo bar baz foo bar)] )->setbadat(1);
-    pdl_is( $p1->uniq, PDL::SV->new( [qw(foo baz bar)] ), 'uniq' );
+    my $p1 =
+      PDL::SV->new( [qw(foo bar baz foo bar)] )->setbadat(1)->setbadat(2);
+    pdl_is( $p1->uniq, PDL::SV->new( [qw(foo bar)] ), 'uniq' );
+
+    pdl_is( $p1->uniqind, pdl( [ 0, 4 ] ), 'uniqind' );
 };
 
 subtest sever => sub {