use strict; # be careful
pp_addpm({At=>'Top'},<<'EOD');
=head1 NAME
PDL::Ufunc - primitive ufunc operations for pdl
=head1 DESCRIPTION
This module provides some primitive and useful functions defined
using PDL::PP based on functionality of what are sometimes called
I<ufuncs> (for example NumPY and Mathematica talk about these).
It collects all the functions generally used to C<reduce> or
C<accumulate> along a dimension. These all do their job across the
first dimension but by using the slicing functions you can do it
on any dimension.
The L<PDL::Reduce|PDL::Reduce> module provides an alternative interface
to many of the functions in this module.
=head1 SYNOPSIS
use PDL::Ufunc;
=cut
use PDL::Slices;
use Carp;
EOD
# check for bad value support
use PDL::Config;
my $bvalflag = $PDL::Config{WITH_BADVAL} || 0;
# should we use the finite() routine in libm ?
# (is the Windows version _finite() ?)
#
pp_addhdr(<<'EOD');
#define IsNaN(x) (x != x)
EOD
# helper functions
sub projectdocs {
my $name = shift;
my $op = shift;
my $extras = shift;
return <<EOD;
=for ref
Project via $name to N-1 dimensions
This function reduces the dimensionality of a piddle
by one by taking the $name along the 1st dimension.
By using L<xchg|PDL::Slices/xchg> etc. it is possible to use
I<any> dimension.
=for usage
\$a = $op(\$b);
=for example
\$spectrum = $op \$image->xchg(0,1)
$extras
EOD
} # sub: projectdocs()
sub cumuprojectdocs {
my $name = shift;
my $op = shift;
my $extras = shift;
return <<EOD;
=for ref
Cumulative $name
This function calculates the cumulative $name
along the 1st dimension.
By using L<xchg|PDL::Slices/xchg> etc. it is possible to use
I<any> dimension.
The sum is started so that the first element in the cumulative $name
is the first element of the parameter.
=for usage
\$a = $op(\$b);
=for example
\$spectrum = $op \$image->xchg(0,1)
$extras
EOD
} # sub: cumuprojectdocs()
# it's a bit unclear what to do with the comparison operators,
# since the return value could be bad because all elements are bad,
# which needs checking for since the bad value could evaluate to
# true or false (eg if the user has set it to 0)
#
# by setting CopyBadStatusCode to '', we stop the output piddle
# from automatically being set bad if any of the input piddles are bad.
# - we can set the flag within BadCode if necessary
#
# This may NOT be sensible. Only time, and comments, will tell...
#
my %over =
(
sumover => { name => 'sum', op => '+=', init => 0, },
prodover => { name => 'product', op => '*=', init => 1, },
);
foreach my $func ( keys %over ) {
# creates $func and cumu$func functions
# and d$func and dcumu$func functions, which
# perform the calculations in double precision
my $name = $over{$func}{name};
my $op = $over{$func}{op};
my $init = $over{$func}{init};
pp_def(
$func,
HandleBad => 1,
Pars => 'a(n); int+ [o]b();',
Code =>
'$GENERIC(b) tmp = ' . $init . ';
loop(n) %{ tmp ' . $op . ' $a(); %}
$b() = tmp;',
BadCode =>
'$GENERIC(b) tmp = ' . $init . ';
int flag = 0;
loop(n) %{
if ( $ISGOOD(a()) ) { tmp ' . $op . ' $a(); flag = 1; }
%}
if ( flag ) { $b() = tmp; }
else { $SETBAD(b()); }',
Doc => projectdocs( $name, $func, '' ),
);
# as above, but in double precision
pp_def(
"d$func",
HandleBad => 1,
Pars => 'a(n); double [o]b();',
Code =>
'double tmp = ' . $init . ';
loop(n) %{ tmp ' . $op . ' $a(); %}
$b() = tmp;',
BadCode =>
'double tmp = ' . $init . ';
int flag = 0;
loop(n) %{
if ( $ISGOOD(a()) ) { tmp ' . $op . ' $a(); flag = 1; }
%}
if ( flag ) { $b() = tmp; }
else { $SETBAD(b()); }',
Doc => projectdocs( $name, "d$func",
"Unlike L<$func|/$func>, the calculations are performed in double\n" .
"precision." ),
);
my $cfunc = "cumu${func}";
pp_def(
$cfunc,
HandleBad => 1,
Pars => 'a(n); int+ [o]b(n);',
Code =>
'$GENERIC(b) tmp = ' . $init . ';
loop(n) %{
tmp ' . $op . ' $a();
$b() = tmp;
%}',
BadCode =>
'$GENERIC(b) tmp = ' . $init . ';
loop(n) %{
if ( $ISBAD(a()) ) { $SETBAD(b()); }
else {
tmp ' . $op . ' $a();
$b() = tmp;
}
%}',
Doc => cumuprojectdocs( $name, $cfunc, '' ),
);
# as above but in double precision
pp_def(
"d$cfunc",
HandleBad => 1,
Pars => 'a(n); double [o]b(n);',
Code =>
'double tmp = ' . $init . ';
loop(n) %{
tmp ' . $op . ' $a();
$b() = tmp;
%}',
BadCode =>
'double tmp = ' . $init . ';
loop(n) %{
if ( $ISBAD(a()) ) { $SETBAD(b()); }
else {
tmp ' . $op . ' $a();
$b() = tmp;
}
%}',
Doc => cumuprojectdocs( $name, $cfunc,
"Unlike L<cumu$func|/cumu$func>, the calculations are performed in double\n" .
"precision." ),
);
} # foreach: my $func
%over =
(
zcover => { txt => '== 0', init => 1, alltypes => 1,
op => 'tmp = tmp && $a() == 0;', check => '!tmp' },
andover => { txt => 'and', init => 1,
op => 'tmp = tmp && $a();', check => '!tmp' },
bandover => { txt => 'bitwise and', init => '~0',
op => 'tmp &= $a();', check => '!tmp' },
orover => { txt => 'or', init => 0,
op => 'tmp = tmp || $a();', check => 'tmp' },
borover => { txt => 'bitwise or', init => 0,
op => 'tmp |= $a();', check => '!~tmp' },
);
foreach my $func ( keys %over ) {
my $txt = $over{$func}{txt};
my $init = $over{$func}{init};
my $op = $over{$func}{op};
my $check = $over{$func}{check};
my %extra = {};
unless ( defined $over{$func}{alltypes} and $over{$func}{alltypes} ) {
$extra{GenericTypes} = ['B','S','U','L'];
}
pp_def(
$func,
HandleBad => 1,
%extra,
Pars => 'a(n); int+ [o]b();',
Code =>
'$GENERIC(b) tmp = ' . $init . ';
loop(n) %{ ' . $op . ' if (' . $check . ') break; %}
$b() = tmp;',
BadCode =>
'$GENERIC(b) tmp = ' . $init . ';
int flag = 0;
loop(n) %{
if ( $ISGOOD(a()) ) { ' . $op . ' flag = 1; if (' . $check . ') break; }
%}
if ( flag ) { $b() = tmp; }
else { $SETBAD(b()); $PDLSTATESETBAD(b); }',
CopyBadStatusCode => '',
Doc => projectdocs( $txt, $func,''),
BadDoc =>
'If C<a()> contains only bad data (and its bad flag is set),
C<b()> is set bad. Otherwise C<b()> will have its bad flag cleared,
as it will not contain any bad values.',
);
} # foreach: $func
# this would need a lot of work to support bad values
# plus it gives me a chance to check out HandleBad => 0 ;)
#
pp_def(
'intover',
HandleBad => 0,
Pars => 'a(n); int+ [o]b();',
Code =>
'$GENERIC(b) tmp = 0;
int ns = $SIZE(n), nn;
/* Integration formulae from Press et al 2nd Ed S 4.1 */
switch (ns) {
case 1:
threadloop %{
$b() = 0.; /* not a(n=>0); as interval has zero width */
%}
break;
case 2:
threadloop %{
$b() = 0.5*($a(n=>0)+$a(n=>1));
%}
break;
case 3:
threadloop %{
$b() = ($a(n=>0)+4*$a(n=>1)+$a(n=>2))/3.;
%}
break;
case 4:
threadloop %{
$b() = ($a(n=>0)+$a(n=>3)+3.*($a(n=>1)+$a(n=>2)))*0.375;
%}
break;
case 5:
threadloop %{
$b() = (14.*($a(n=>0)+$a(n=>4))
+64.*($a(n=>1)+$a(n=>3))
+24.*$a(n=>2))/45.;
%}
break;
default:
threadloop %{
for (nn=3,tmp=0;nn<ns-3;nn++) { tmp += $a(n=>nn); }
tmp += (23./24.)*($a(n=>2)+$a(n=>nn));nn++;
tmp += (7./6.) *($a(n=>1)+$a(n=>nn));nn++;
tmp += 0.375 *($a(n=>0)+$a(n=>nn));
$b() = tmp;
%}
}
',
Doc => projectdocs('integral','intover',
q~Notes:
For C<n E<gt> 3>, these are all C<O(h^4)> (like Simpson's rule), but are
integrals between the end points assuming the pdl gives values just at
these centres: for such `functions', sumover is correct to C<O(h)>, but
is the natural (and correct) choice for binned data, of course.
~)
); # intover
pp_def(
'average',
HandleBad => 1,
Pars => 'a(n); int+ [o]b();',
Code =>
'$GENERIC(b) tmp = 0;
loop(n) %{ tmp += $a(); %}
$b() = tmp / ($GENERIC(b)) $SIZE(n);',
BadCode =>
'$GENERIC(b) tmp = 0;
long cnt = 0;
loop(n) %{
if ( $ISGOOD(a()) ) { tmp += $a(); cnt++; }
%}
if ( cnt ) { $b() = tmp / ($GENERIC(b)) cnt; }
else { $SETBAD(b()); }',
Doc => projectdocs( 'average', 'average', '' ),
);
# do the above calculation, but in double precision
pp_def(
'daverage',
HandleBad => 1,
Pars => 'a(n); double [o]b();',
Code =>
'double tmp = 0;
long cnt = 0;
loop(n) %{ tmp += $a(); cnt++; %}
$b() = tmp / cnt;',
BadCode =>
'double tmp = 0;
long cnt = 0;
loop(n) %{
if ( $ISGOOD(a()) ) { tmp += $a(); cnt++; }
%}
if ( cnt ) { $b() = tmp / cnt; }
else { $SETBAD(b()); }',
Doc => projectdocs( 'average', 'daverage',
"Unlike L<average|/average>, the calculation is performed in double\n" .
"precision." ),
);
# Internal utility sorting routine for median/qsort routines.
#
# note: we export them to the PDL Core structure for use in
# other modules (eg Image2D)
for (keys %PDL::Types::typehash) {
my $ctype = $PDL::Types::typehash{$_}{ctype};
my $ppsym = $PDL::Types::typehash{$_}{ppsym};
pp_add_boot( " PDL->qsort_${ppsym} = pdl_qsort_${ppsym};" .
" PDL->qsort_ind_${ppsym} = pdl_qsort_ind_${ppsym};\n" );
pp_addhdr("
void pdl_qsort_$ppsym($ctype* xx, int a, int b) {
int i,j;
$ctype t, median;
i = a; j = b;
median = xx[(i+j) / 2];
do {
while (xx[i] < median)
i++;
while (median < xx[j])
j--;
if (i <= j) {
t = xx[i]; xx[i] = xx[j]; xx[j] = t;
i++; j--;
}
} while (i <= j);
if (a < j)
pdl_qsort_$ppsym(xx,a,j);
if (i < b)
pdl_qsort_$ppsym(xx,i,b);
}
void pdl_qsort_ind_$ppsym($ctype* xx, int* ix, int a, int b) {
int i,j;
int t;
$ctype median;
i = a; j = b;
median = xx[ix[(i+j) / 2]];
do {
while (xx[ix[i]] < median)
i++;
while (median < xx[ix[j]])
j--;
if (i <= j) {
t = ix[i]; ix[i] = ix[j]; ix[j] = t;
i++; j--;
}
} while (i <= j);
if (a < j)
pdl_qsort_ind_$ppsym(xx,ix,a,j);
if (i < b)
pdl_qsort_ind_$ppsym(xx,ix,i,b);
}
");
}
# when copying the data over to the temporary array,
# ignore the bad values and then only send the number
# of good elements to the sort routines
#
sub generic_qsort {
my $pdl = shift;
return '$TBSULFD(pdl_qsort_B,pdl_qsort_S,pdl_qsort_U,
pdl_qsort_L,pdl_qsort_F,pdl_qsort_D) ($P(' . $pdl . '), 0, nn);';
}
# should use threadloop ?
#
my $copy_to_temp_good = '
int nn, nn1;
loop(n) %{ $tmp() = $a(); %}
nn = $COMP(__n_size)-1; ' .
generic_qsort('tmp');
my $copy_to_temp_bad = '
register int nn = 0;
loop(n) %{
if ( $ISGOOD(a()) ) { $tmp(n=>nn) = $a(); nn++; }
%}
if ( nn == 0 ) {
$SETBAD(b());
} else {
';
my $find_median_average = '
nn1 = nn/2; nn2 = nn1+1;
if (nn%2==0) {
$b() = $tmp(n => nn1);
}
else {
$b() = 0.5*( $tmp(n => nn1) + $tmp(n => nn2) );
}';
my $find_median_lower = '
nn1 = nn/2;
$b() = $tmp(n => nn1);';
pp_def(
'medover',
HandleBad => 1,
Pars => 'a(n); [o]b(); [t]tmp(n);',
Doc => projectdocs('median','medover',''),
Code =>
"int nn2;\n" . $copy_to_temp_good . $find_median_average,
BadCode =>
$copy_to_temp_bad .
' int nn1, nn2;
nn -= 1; ' .
generic_qsort('tmp') .
$find_median_average . '}',
); # pp_def: medover
pp_def(
'oddmedover',
HandleBad => 1,
Pars => 'a(n); [o]b(); [t]tmp(n);',
Doc => projectdocs('oddmedian','oddmedover','
The median is sometimes not a good choice as if the array has
an even number of elements it lies half-way between the two
middle values - thus it does not always correspond to a data
value. The lower-odd median is just the lower of these two values
and so it ALWAYS sits on an actual data value which is useful in
some circumstances.
'),
Code =>
$copy_to_temp_good . $find_median_lower,
BadCode =>
$copy_to_temp_bad .
' int nn1;
nn -= 1; '.
$find_median_lower . '}',
); # pp_def: oddmedover
pp_def('pctover',
Pars => 'a(n); p(); [o]b(); [t]tmp(n);',
Doc => '
Project via percentile to N-1 dimensions
This function reduces the dimensionality of a piddle by one by finding
the specified percentile (p) along the 1st dimension. The specified
percentile must be between 0.0 and 1.0. When the specified percentile
falls between data points, the result is interpolated.
By using L<xchg|PDL::Slices/xchg> etc. it is possible to use
I<any> dimension.
=for usage
$a = pctover($b, $p);
=for example
$spectrum = pctover $image->xchg(0,1) $p
=cut
',
Code => '
int nn, nn1, nn2;
double pp1, pp2;
loop(n) %{ $tmp() = $a(); %}
nn = $COMP(__n_size)-1;
$TBSULFD(pdl_qsort_B,pdl_qsort_S,pdl_qsort_U,
pdl_qsort_L,pdl_qsort_F,pdl_qsort_D) ($P(tmp), 0, nn);
nn1 = (nn + 1)*$p() - 1 + 0.5; nn2 = nn1+1;
if (nn2 > nn) nn2 = nn;
if (nn1 > nn) nn1 = nn;
pp1 = (double)nn1/(double)nn;
pp2 = (double)nn2/(double)nn;
if ($tmp(n => nn2) == $tmp(n => nn1)) {
$b() = $tmp(n => nn1);
} else if ($p() == pp1) {
$b() = $tmp(n => nn1);
} else if ($p() == pp2) {
$b() = $tmp(n => nn2);
} else {
$b() = ($p() - pp1)/(pp2 - pp1)*
( $tmp(n => nn2) - $tmp(n => nn1) ) + $tmp(n => nn1);
}
');
pp_def('oddpctover',
Pars => 'a(n); p(); [o]b(); [t]tmp(n);',
Doc => '
Project via percentile to N-1 dimensions
This function reduces the dimensionality of a piddle by one by finding
the specified percentile along the 1st dimension. The specified
percentile must be between 0.0 and 1.0. When the specified percentile
falls between two values, the nearest data value is the result.
By using L<xchg|PDL::Slices/xchg> etc. it is possible to use
I<any> dimension.
=for usage
$a = oddpctover($b, $p);
=for example
$spectrum = oddpctover $image->xchg(0,1) $p
=cut
',
Code => '
int nn, nn1;
loop(n) %{ $tmp() = $a(); %}
nn = $COMP(__n_size)-1;
$TBSULFD(pdl_qsort_B,pdl_qsort_S,pdl_qsort_U,
pdl_qsort_L,pdl_qsort_F,pdl_qsort_D) ($P(tmp), 0, nn);
nn1 = (nn + 1)*$p() - 1 + 0.5;
if (nn1 > nn) nn1 = nn;
if (nn1 < 0) nn1 = 0;
$b() = $tmp(n => nn1);
');
pp_add_exported('', 'pct');
pp_addpm(<<"EOD");
=head2 pct
=for ref
Return the specified percentile of all elements in a piddle. The
specified percentile (p) must be between 0.0 and 1.0. When the
specified percentile falls between data points, the result is
interpolated.
=for usage
\$x = pct(\$data, \$pct);
=cut
*pct = \\&PDL::pct;
sub PDL::pct {
my(\$x, \$p) = \@_;
my \$tmp;
\$x->clump(-1)->pctover(\$p, \$tmp=PDL->nullcreate(\$x));
return \$tmp->at();
}
EOD
pp_add_exported('', 'oddpct');
pp_addpm(<<"EOD");
=head2 oddpct
=for ref
Return the specified percentile of all elements in a piddle. The
specified percentile must be between 0.0 and 1.0. When the specified
percentile falls between two values, the nearest data value is the
result.
=for usage
\$x = oddpct(\$data, \$pct);
=cut
*oddpct = \\&PDL::oddpct;
sub PDL::oddpct {
my(\$x, \$p) = \@_;
my \$tmp;
\$x->clump(-1)->oddpctover(\$p, \$tmp=PDL->nullcreate(\$x));
return \$tmp->at();
}
EOD
# Generate small ops functions to do entire array
#
# How to handle a return value of BAD - ie what
# datatype to use?
#
for my $op ( ['avg','average','average'],
['sum','sumover','sum'],
['prod','prodover','product'],
['davg','daverage','average (in double precision)'],
['dsum','dsumover','sum (in double precision)'],
['dprod','dprodover','product (in double precision)'],
['zcheck','zcover','check for zero'],
['and','andover','logical and'],
['band','bandover','bitwise and'],
['or','orover','logical or'],
['bor','borover','bitwise or'],
['min','minimum','minimum'],
['max','maximum','maximum'],
['median', 'medover', 'median'],
['oddmedian','oddmedover','oddmedian']) {
my $name = $op->[0];
my $func = $op->[1];
my $text = $op->[2];
pp_add_exported('', $name);
pp_addpm(<<"EOD");
=head2 $name
=for ref
Return the $text of all elements in a piddle
=for usage
\$x = $name(\$data);
EOD
if ( $bvalflag ) {
pp_addpm(<<"EOD");
=for bad
This routine handles bad values (see the
documentation for L<$func|/$func>).
I still need to decide how to handle the case when
the return value is a bad value (eg to make sure it
has the same type as the input piddle OR
perhaps we should die - makes sense for the conditional
ops but not things like sum)
EOD
} # if: bvalflag
pp_addpm(<<"EOD");
=cut
*$name = \\&PDL::$name;
sub PDL::$name {
my(\$x) = \@_; my \$tmp;
\$x->clump(-1)->${func}( \$tmp=PDL->nullcreate(\$x) );
return \$tmp->at();
}
EOD
} # for $op
pp_add_exported('','any all');
pp_addpm(<<'EOPM');
=head2 any
=for ref
Return true if any element in piddle set
Useful in conditional expressions:
=for example
if (any $a>15) { print "some values are greater than 15\n" }
EOPM
if ( $bvalflag ) {
pp_addpm(<<'EOPM');
=for bad
See L<or|/or> for comments on what happens when all elements
in the check are bad.
EOPM
} # if: bvalflag
pp_addpm(<<'EOPM');
=cut
*any = \∨
*PDL::any = \&PDL::or;
=head2 all
=for ref
Return true if all elements in piddle set
Useful in conditional expressions:
=for example
if (all $a>15) { print "all values are greater than 15\n" }
EOPM
if ( $bvalflag ) {
pp_addpm(<<'EOPM');
=for bad
See L<and|/and> for comments on what happens when all elements
in the check are bad.
EOPM
} # IF: BVALFLAG
pp_addpm(<<'EOPM');
=cut
*all = \∧
*PDL::all = \&PDL::and;
EOPM
pp_addpm(<<'EOD'
=head2 minmax
=for ref
Returns an array with minimum and maximum values of a piddle.
=for usage
($mn, $mx) = minmax($pdl);
This routine does I<not> thread over the dimensions of C<$pdl>;
it returns the minimum and maximum values of the whole array.
See L<minmaximum|/minmaximum> if this is not what is required.
The two values are returned as Perl scalars similar to min/max.
=for example
perldl> $x = pdl [1,-2,3,5,0]
perldl> ($min, $max) = minmax($x);
perldl> p "$min $max\n";
-2 5
=cut
*minmax = \&PDL::minmax;
sub PDL::minmax {
my ($x)=@_; my $tmp;
my @arr = $x->clump(-1)->minmaximum;
return map {$_->sclr} @arr[0,1]; # return as scalars !
}
EOD
);
pp_add_exported('', 'minmax');
#pp_add_exported('', 'minmax_ind');
# move all bad values to the end of the array
#
pp_def(
'qsort',
HandleBad => 1,
Pars => 'a(n); [o]b(n);',
Code =>
'int nn;
loop(n) %{ $b() = $a(); %}
nn = $COMP(__n_size)-1;
' . generic_qsort('b'),
BadCode =>
'register int nn = 0, nb = $SIZE(n) - 1;
loop(n) %{
if ( $ISGOOD(a()) ) { $b(n=>nn) = $a(); nn++; }
else { $SETBAD(b(n=>nb)); nb--; }
%}
if ( nn != 0 ) {
nn -= 1;
' . generic_qsort('b') . ' }',
Doc => '
=for ref
Quicksort a vector into ascending order.
=for example
print qsort random(10);
',
BadDoc =>
'
Bad values are moved to the end of the array:
perldl> p $b
[42 47 98 BAD 22 96 74 41 79 76 96 BAD 32 76 25 59 BAD 96 32 BAD]
perldl> p qsort($b)
[22 25 32 32 41 42 47 59 74 76 76 79 96 96 96 98 BAD BAD BAD BAD]
',
); # pp_def qsort
sub generic_qsort_ind {
return '$TBSULFD(pdl_qsort_ind_B,pdl_qsort_ind_S,pdl_qsort_ind_U,
pdl_qsort_ind_L,pdl_qsort_ind_F,pdl_qsort_ind_D) ($P(a), $P(indx),
0, nn);';
}
pp_def(
'qsorti',
HandleBad => 1,
Pars => 'a(n); int [o]indx(n);',
Code =>
'int nn = $COMP(__n_size)-1;
loop(n) %{
$indx() = n;
%}
' . generic_qsort_ind(),
BadCode =>
'register int nn = 0, nb = $SIZE(n) - 1;
loop(n) %{
if ( $ISGOOD(a()) ) { $indx(n=>nn) = n; nn++; } /* play safe since nn used more than once */
else { $indx(n=>nb) = n; nb--; }
%}
if ( nn != 0 ) {
nn -= 1;
' . generic_qsort_ind() . ' }',
BadDoc =>
'Bad elements are moved to the end of the array:
perldl> p $b
[42 47 98 BAD 22 96 74 41 79 76 96 BAD 32 76 25 59 BAD 96 32 BAD]
perldl> p $b->index( qsorti($b) )
[22 25 32 32 41 42 47 59 74 76 76 79 96 96 96 98 BAD BAD BAD BAD]
',
Doc => '
=for ref
Quicksort a vector and return index of elements in ascending order.
=for example
$ix = qsorti $a;
print $a->index($ix); # Sorted list
'
); # pp_def: qsorti
# I don't think the old behaviour is correct in the presence of NaN's -
# surely it will set the min/max values to NaN in this case?
#
# I have kept in the check for when Bad value support is not being compiled
#
my $nan_check = $bvalflag ? '' : '|| IsNaN(cur)';
for my $which (
['minimum','<'],
['maximum','>']
) {
my $name = $which->[0];
my $op = $which->[1];
pp_def(
$name,
HandleBad => 1,
Pars => 'a(n); [o]c();',
Code =>
'$GENERIC() cur;
loop(n) %{
if(!n || $a() '.$op.' cur ' . $nan_check . ') {cur = $a();}
%}
$c() = cur;',
BadCode =>
'$GENERIC() cur;
int flag = 0;
loop(n) %{
if( $ISGOOD(a()) && (!flag || $a() '.$op.' cur)) {cur = $a(); flag = 1;}
%}
if ( flag ) { $c() = cur; }
else { $SETBAD(c()); $PDLSTATESETBAD(c); }',
CopyBadStatusCode => '',
Doc => projectdocs($name,$name),
BadDoc =>
'Output is set bad if all elements of the input are bad,
otherwise the bad flag is cleared for the output piddle.
Note that C<NaNs> are considered to be valid values;
see L<isfinite|PDL::Math/isfinite> and L<badmask|PDL::Math/badmask>
for ways of masking NaNs.
',
);
pp_def(
"${name}_ind",
HandleBad => 1,
Pars => 'a(n); int [o] c();',
Code =>
'$GENERIC() cur;
int curind;
loop(n) %{
if(!n || $a() '.$op.' cur ' . $nan_check . ')
{cur = $a(); curind = n;}
%}
$c() = curind;',
BadCode =>
'$GENERIC() cur;
int curind, flag = 0; /* should set curind to -1 and check for that, then do not need flag */
loop(n) %{
if( $ISGOOD(a()) && (!flag || $a() '.$op.' cur))
{cur = $a(); curind = n; flag = 1;}
%}
if ( flag ) { $c() = curind; }
else { $SETBAD(c()); $PDLSTATESETBAD(c); }',
CopyBadStatusCode => '',
Doc => "Like $name but returns the index rather than the value",
BadDoc =>
'Output is set bad if all elements of the input are bad,
otherwise the bad flag is cleared for the output piddle.',
);
pp_def(
"${name}_n_ind",
HandleBad => 0, # just a marker
Pars => 'a(n); int[o]c(m);',
Code =>
'$GENERIC() cur; int curind; register int ns = $SIZE(n);
if($SIZE(m) > $SIZE(n)) $CROAK("n_ind: m_size > n_size");
loop(m) %{
curind = ns;
loop(n) %{
int nm; int flag=0;
for(nm=0; nm<m; nm++) {
if($c(m=>nm) == n) {flag=1; break;}
}
if(!flag &&
((curind == ns) || $a() '.$op.' cur || IsNaN(cur)))
{cur = $a(); curind = n;}
%}
$c() = curind;
%}',
Doc => "Returns the index of C<m> $name elements",
BadDoc => 'Not yet been converted to ignore bad values',
);
} # foreach: $which
# removed IsNaN handling, even from Code section
# I think it was wrong, since it was
#
# if (!n || ($a() < curmin) || IsNaN(curmin)) {curmin = $a(); curmin_ind = n;};
# if (!n || ($a() > curmax) || IsNaN(curmax)) {curmax = $a(); curmax_ind = n;};
#
# surely this succeeds if cur... is a NaN??
#
pp_def(
'minmaximum',
HandleBad => 1,
Pars => 'a(n); [o]cmin(); [o] cmax(); int [o]cmin_ind(); int [o]cmax_ind();',
Code =>
'$GENERIC() curmin, curmax;
int curmin_ind, curmax_ind;
loop(n) %{
if ( !n ) {
curmin = curmax = $a();
curmin_ind = curmax_ind = n;
} else {
if ( $a() < curmin ) { curmin = $a(); curmin_ind = n; }
if ( $a() > curmax ) { curmax = $a(); curmax_ind = n; }
}
%}
$cmin() = curmin; $cmin_ind() = curmin_ind;
$cmax() = curmax; $cmax_ind() = curmax_ind;',
CopyBadStatusCode => '',
BadCode =>
'$GENERIC() curmin, curmax;
int curmin_ind, curmax_ind, flag = 0;
loop(n) %{
if ( $ISGOOD(a()) ) {
if ( !flag ) {
curmin = curmax = $a();
curmin_ind = curmax_ind = n;
flag = 1;
} else {
if ( $a() < curmin ) { curmin = $a(); curmin_ind = n; }
if ( $a() > curmax ) { curmax = $a(); curmax_ind = n; }
}
} /* ISGOOD */
%}
if ( flag ) {
$cmin() = curmin; $cmin_ind() = curmin_ind;
$cmax() = curmax; $cmax_ind() = curmax_ind;
} else {
$SETBAD(cmin()); $SETBAD(cmin_ind());
$SETBAD(cmax()); $SETBAD(cmax_ind());
$PDLSTATESETBAD(cmin); $PDLSTATESETBAD(cmin_ind);
$PDLSTATESETBAD(cmax); $PDLSTATESETBAD(cmax_ind);
}',
Doc =>
'
=for ref
Find minimum and maximum and their indices for a given piddle;
=for usage
perldl> $a=pdl [[-2,3,4],[1,0,3]]
perldl> ($min, $max, $min_ind, $max_ind)=minmaximum($a)
perldl> p $min, $max, $min_ind, $max_ind
[-2 0] [4 3] [0 1] [2 2]
See also L<minmax|/minmax>, which clumps the piddle together.
',
BadDoc =>
'If C<a()> contains only bad data, then the output piddles will
be set bad, along with their bad flag.
Otherwise they will have their bad flags cleared,
since they will not contain any bad values.',
); # pp_def minmaximum
pp_addpm({At=>'Bot'},<<'EOD');
=head1 AUTHOR
Copyright (C) Tuomas J. Lukka 1997 (lukka@husc.harvard.edu).
Contributions by Christian Soeller (c.soeller@auckland.ac.nz)
and Karl Glazebrook (kgb@aaoepp.aao.gov.au). All rights
reserved. There is no warranty. You are allowed to redistribute this
software / documentation under certain conditions. For details, see
the file COPYING in the PDL distribution. If this file is separated
from the PDL distribution, the copyright notice should be included in
the file.
=cut
EOD
pp_done();