add demo

Changes

@@ -1,3 +1,5 @@
+- add perldl demo
+
 0.83 2022-07-17
 - immediate re-release to fix packaging problem
 

Demo.pm

@@ -0,0 +1,222 @@
+package PDL::Demos::PLplot;
+use PDL::Graphics::PLplot;
+
+sub info {('plplot', 'PLplot graphics output')}
+
+sub init {'
+use PDL::Graphics::PLplot;
+use Data::Dumper;
+'}
+my @demo = (
+[comment => q|
+  Welcome to this tour of the PDL's PLplot interface.
+
+  This tour will introduce the PDL's PLplot plotting module and show
+  what this powerful package can provide in terms of plotting, though it is
+  not designed to give a full tour of PLplot.
+|],
+
+[act => q|
+  # ensure the module is loaded
+  use PDL::Graphics::PLplot;
+  # PLplot uses "devices". This installation of PLplot supports these:
+  $devs = plgDevs();
+  print Dumper($devs);
+|],
+
+[act => q[
+  ($dev) = grep $devs->{$_}, qw(qtwidget wxwidgets xcairo xwin wingcc);
+  die "No suitable GUI device found" if !$dev;
+  print "We'll use '$dev'\n";
+  # Initialise the window
+  $w = PDL::Graphics::PLplot->new( DEV=>$dev, PAGESIZE=>[600,400] );
+  plspause(0);
+  # set up colourmap for first 2 demos
+  $i = pdl [0.0,1.0]; # left/right boundary
+  ($h, $l, $s) = (pdl(240, 0), pdl(0.6, 0.6), pdl(0.8, 0.8));
+  plscmap1n(256);
+  plscmap1l(0, $i, $h, $l, $s, pdl []);
+]],
+
+[act => q[
+  # plot data of example 8
+  ($XPTS, $YPTS) = (35, 45);
+  ($indexxmin, $indexxmax) = (0, $XPTS);
+  # parameters of ellipse (in x, y index coordinates) that limits the data.
+  # x0, y0 correspond to the exact floating point centre of the index range.
+  ($x0, $y0) = (0.5 * ( $XPTS - 1 ), 0.5 * ( $YPTS - 1 ));
+  ($a, $b) = (0.9 * $x0, 0.7 * $y0);
+  ($x, $y) = map +(sequence($_) - int($_ / 2)) / int($_ / 2), $XPTS, $YPTS;
+  ($xx, $yy) = ($x->dummy(1,$YPTS), $y->dummy(0,$XPTS));
+  $r = sqrt ($xx * $xx + $yy * $yy);
+  $z = exp (-$r * $r) * cos (2.0 * PI * $r);
+  $z->inplace->setnonfinitetobad;
+  $z->inplace->setbadtoval(-5); # -MAXFLOAT would mess-up up the scale
+  ($zmin, $zmax) = (min($z), max($z));
+  $square_root = sqrt(1. - hclip( (( sequence($XPTS) - $x0 ) / $a) ** 2, 1 ));
+  # Add 0.5 to find nearest integer and therefore preserve symmetry
+  # with regard to lower and upper bound of y range.
+  $indexymin = lclip( 0.5 + $y0 - $b * $square_root, 0 )->indx;
+  # indexymax calculated with the convention that it is 1
+  # greater than highest valid index.
+  $indexymax = hclip( 1 + ( 0.5 + $y0 + $b * $square_root ), $YPTS )->indx;
+  $zlimited = zeroes ($XPTS, $YPTS);
+  for my $i ( $indexxmin..$indexxmax-1 ) {
+    my $j = [ $indexymin->at($i), $indexymax->at($i) ];
+    $zlimited->index($i)->slice($j) .= $z->index($i)->slice($j);
+  }
+  $nlevel = 10;
+  $step = ($zmax - $zmin) / ($nlevel + 1);
+  $clevel = $zmin + $step + $step * sequence($nlevel);
+  # display the plot of example 8
+  pllightsource(1., 1., 1.);
+  pladv(0);
+  plvpor(0.0, 1.0, 0.0, 0.9);
+  plwind(-1.0, 1.0, -0.9, 1.1);
+  plcol0(3);
+  plmtex(1.0, 0.5, 0.5, "t", "#frPLplot Example 8 - Alt=60, Az=30");
+  plcol0(1);
+  plw3d(1.0, 1.0, 1.0, -1.0, 1.0, -1.0, 1.0, $zmin, $zmax, 60.0, 30.0);
+  plbox3 (0.0, 0, 0.0, 0, 0.0, 0,
+    "bnstu", "x axis", "bnstu", "y axis", "bcdmnstuv", "z axis");
+  plcol0 (2);
+  plsurf3d($x, $y, $z, MAG_COLOR | FACETED, pdl []);
+  plflush();
+]],
+
+[act => q[
+  # plot data of example 11
+  ($XPTS, $YPTS) = (35, 46);
+  ($x, $y) = map 3*(sequence($_) - int($_ / 2)) / int($_ / 2), $XPTS, $YPTS;
+  ($xx, $yy) = ($x->dummy(1,$YPTS), $y->dummy(0,$XPTS));
+  $z =
+    3. * (1.-$xx)*(1.-$xx) * exp(-($xx*$xx) - ($yy+1.)*($yy+1.)) -
+    10. * ($xx/5. - pow($xx,3.) - pow($yy,5.)) * exp(-$xx*$xx-$yy*$yy) -
+    1./3. * exp(-($xx+1)*($xx+1) - ($yy*$yy));
+  ($zmin, $zmax) = (min($z), max($z));
+  $nlevel = 10;
+  $step = ($zmax - $zmin) / ($nlevel + 1);
+  $clevel = $zmin + $step + $step * sequence($nlevel);
+  # display the plot of example 11
+  pladv(0);
+  plcol0(1);
+  plvpor(0.0, 1.0, 0.0, 0.9);
+  plwind (-1.0, 1.0, -1.0, 1.5);
+  plw3d (1.0, 1.0, 1.2, -3.0, 3.0, -3.0, 3.0, $zmin, $zmax, 17.0, 115.0);
+  plbox3 (0.0, 0, 0.0, 0, 0.0, 4,
+          "bnstu", "x axis", "bnstu", "y axis", "bcdmnstuv", "z axis");
+  plcol0(2);
+  plmeshc($x, $y, $z, DRAW_LINEXY | MAG_COLOR | BASE_CONT, $clevel);
+  plcol0(3);
+  plmtex(1.0, 0.5, 0.5, "t", "#frPLplot Example 11 - Alt=17, Az=115, Opt=3");
+  plflush();
+]],
+
+[act => q[
+  # plot data of example 22.4
+  $arrow2_x = pdl [-0.5, 0.3, 0.3, 0.5, 0.3,  0.3];
+  $arrow2_y = pdl [0.0,  0.0, 0.2, 0.0, -0.2, 0.0];
+  plsvect($arrow2_x, $arrow2_y, 1);
+  ($nx, $ny, $nc, $nseg) = (20, 20, 11, 20);
+  ($dx, $dy) = (1.0, 1.0);
+  ($xmin, $xmax) = (-$nx / 2 * $dx, $nx / 2 * $dx);
+  ($ymin, $ymax) = (-$ny / 2 * $dy, $ny / 2 * $dy);
+  $x = ((sequence($nx)-int($nx/2)+0.5)*$dx)->dummy(1,$ny);
+  $y = ((sequence($ny)-int($ny/2)+0.5)*$dy)->dummy(0,$nx);
+  $cgrid2 = plAlloc2dGrid($x, $y);
+  $Q = 2.0;
+  $b = $ymax/4.0*(3-cos(PI*$x/$xmax));
+  $dbdx = $ymax/4.0*sin(PI*$x/$xmax)*PI/$xmax*$y/$b;
+  $u = $Q*$ymax/$b;
+  $v = zeroes($nx, $ny);
+  $clev = (sequence($nc) * $Q / ($nc - 1)) + $Q;
+  # display the plot of example 22.4
+  plstransform( sub {
+    my ($x, $y, $xmax) = @_;
+    return ($x, $y / 4.0 * ( 3 - cos( PI * $x / $xmax ) ));
+  }, $xmax );
+  plenv($xmin, $xmax, $ymin, $ymax, 0, 0);
+  pllab("(x)", "(y)", "#frPLplot Example 22 - constriction with plstransform");
+  plcol0( 2 );
+  plshades( $u,
+      $xmin + $dx / 2, $xmax - $dx / 2, $ymin + $dy / 2, $ymax - $dy / 2,
+      $clev, 0.0, 1, 1.0, 0, 0, 0, 0 );
+  plvect($u,$v,-1.0,\&pltr2,$cgrid2);
+  # Plot edges using plpath (which accounts for coordinate transformation) rather than plline
+  plpath( $nseg, $xmin, $ymax, $xmax, $ymax );
+  plpath( $nseg, $xmin, $ymin, $xmax, $ymin );
+  plcol0( 1 );
+  plstransform( undef, undef );
+  plflush();
+]],
+
+[act => q[
+  # plot data of example 22.5
+  $nper = 100;
+  $nlevel = 10;
+  $rmax = $nr = $ntheta = 20;
+  ($eps, $q1, $q2) = (2, 1, -1);
+  ($d1, $d2) = ($rmax / 4, $rmax / 4);
+  ($q1i, $d1i) = (- $q1 * $rmax / $d1, $rmax * $rmax / $d1);
+  ($q2i, $d2i) = (- $q2 * $rmax / $d2, $rmax * $rmax / $d2);
+  $r = (0.5 + sequence ($nr))->dummy (1, $ntheta);
+  $theta = (2 * PI / ($ntheta - 1) *
+               (0.5 + sequence ($ntheta)))->dummy (0, $nr);
+  ($x, $y) = ($r * cos ($theta), $r * sin ($theta));
+  ($div1, $div1i) =
+    map sqrt(($x - $_) ** 2 + ($y - $_) ** 2 + $eps * $eps), $d1, $d1i;
+  ($div2, $div2i) =
+    map sqrt(($x - $_) ** 2 + ($y + $_) ** 2 + $eps * $eps), $d2, $d2i;
+  $z = $q1 / $div1 + $q1i / $div1i + $q2 / $div2 + $q2i / $div2i;
+  $u = -$q1 * ($x - $d1) / ($div1**3) - $q1i * ($x - $d1i) / ($div1i ** 3)
+          -$q2 * ($x - $d2) / ($div2**3) - $q2i * ($x - $d2i) / ($div2i ** 3);
+  $v = -$q1 * ($y - $d1) / ($div1**3) - $q1i * ($y - $d1i) / ($div1i ** 3)
+          -$q2 * ($y + $d2) / ($div2**3) - $q2i * ($y + $d2i) / ($div2i ** 3);
+  ($xmin, $xmax, $ymin, $ymax, $zmin, $zmax) = map minmax($_), $x, $y, $z;
+  # Plot contours of the potential
+  $dz = ($zmax - $zmin) / $nlevel;
+  $clevel = $zmin + (sequence ($nlevel) + 0.5) * $dz;
+  # the perimeter of the cylinder
+  $theta = (2 * PI / ($nper - 1)) * sequence ($nper);
+  ($px, $py) = ($rmax * cos ($theta), $rmax * sin ($theta));
+  # display the plot of example 22.5
+  plenv ($xmin, $xmax, $ymin, $ymax, 0, 0);
+  pllab ("(x)", "(y)",
+         "#frPLplot Example 22 - potential gradient vector plot");
+  plcol0 (3);
+  pllsty (2);
+  my $cgrid2 = plAlloc2dGrid ($x, $y);
+  plcont ($z, 1, $nr, 1, $ntheta, $clevel, \&pltr2, $cgrid2);
+  pllsty (1);
+  plcol0 (1);
+  # Plot the vectors of the gradient of the potential
+  plcol0 (2);
+  plvect ($u, $v, 25.0, \&pltr2, $cgrid2);
+  plcol0 (1);
+  plline ($px , $py); # Plot the cylinder
+  plflush();
+]],
+
+[actnw => q|
+  # close the window--we're done!
+  $w->close;
+  undef $w;
+
+  # These are just a few of the amazing demos of PLplot. See their homepage at
+  #      https://plplot.sourceforge.net/examples.php
+|],
+);
+
+sub demo { @demo }
+
+1;
+
+=head1 NAME
+
+PDL::Demos::PLplot - demonstrate PDL::Graphics::PLplot capabilities
+
+=head1 SYNOPSIS
+
+  pdl> demo plplot
+
+=cut

MANIFEST

@@ -1,5 +1,6 @@
 callback.c
 Changes
+Demo.pm
 Makefile.PL
 MANIFEST			This list of files
 MANIFEST.SKIP

Makefile.PL

@@ -73,7 +73,7 @@ close   $fh;
 my @pack = ([qw(plplot.pd PLplot PDL::Graphics::PLplot), undef, 1]);
 
 my %hash = pdlpp_stdargs(@pack);
-$hash{'PREREQ_PM'} = { PDL => 0 };
+$hash{PREREQ_PM} = { PDL => 0 };
 $hash{CONFIGURE_REQUIRES} = {
   'PDL::Core::Dev' => 0,
   'Devel::CheckLib' => 0,
@@ -83,10 +83,10 @@ $hash{CONFIGURE_REQUIRES} = {
 $hash{TEST_REQUIRES} = {
   'Test::More' => '0.88', # done_testing
 };
-$hash{'VERSION_FROM'}   = 'plplot.pd';
+$hash{VERSION_FROM}   = 'plplot.pd';
 $hash{OBJECT} .= ' callback$(OBJ_EXT)';
-$hash{'LIBS'}      = [$libs];
-$hash{'INC'}      .= " $plplot_include_path";
+$hash{LIBS}      = [$libs];
+$hash{INC}      .= " $plplot_include_path";
 $hash{clean}{FILES} .= ' *svg.* *.xfig temp* OPTIONS!';
 $hash{META_MERGE} = {
   "meta-spec" => { version => 2 },
@@ -100,6 +100,7 @@ $hash{META_MERGE} = {
     x_IRC => 'irc://irc.perl.org/#pdl',
   },
 };
+$hash{PM}{'Demo.pm'} = '$(INST_LIB)/PDL/Demos/PLplot.pm';
 
 my $postamble = pdlpp_postamble(@pack);
 

t/x22.pl

@@ -37,10 +37,10 @@
 
 # Pairs of points making the line segments used to plot the user defined
 # arrow
-my $arrow_x = pdl [-0.5, 0.5, 0.3, 0.5, 0.3, 0.5];
-my $arrow_y = pdl [0.0, 0.0,   0.2, 0.0, -0.2, 0.0];
-my $arrow2_x = pdl [-0.5, 0.3, 0.3, 0.5, 0.3, 0.3];
-my $arrow2_y = pdl [0.0, 0.0,   0.2, 0.0, -0.2, 0.0];
+my $arrow_x =  pdl [-0.5, 0.5, 0.3, 0.5, 0.3,  0.5];
+my $arrow_y =  pdl [0.0,  0.0, 0.2, 0.0, -0.2, 0.0];
+my $arrow2_x = pdl [-0.5, 0.3, 0.3, 0.5, 0.3,  0.3];
+my $arrow2_y = pdl [0.0,  0.0, 0.2, 0.0, -0.2, 0.0];
 
 #
 # Vector plot of the circulation about the origin