in reply to Geo::Shapefile::Writer help

Welcome, kjslover! As tangent showed, it is easy to input arrays of any size. It should be possible to generate the required data with a suitable tool with the data output to a format easily read by your script and fed to the shape generator.

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Re^2: Geo::Shapefile::Writer help
by kjslover (Initiate) on Jan 28, 2016 at 19:57 UTC

    Thanks to both tangent and u65. While the ease of inputting the numbers into the $shape object makes sense, how might I do this with an array that I am creating? I currently have an @coords array that I am placing my x,y values in. How do I transform this into the $shape object that tangent has referenced?
    I apologize if this is a basic question... I am self-taught in the ways of Perl and learn mainly from the O'Reilly books and online resources

[reply]
      How do I transform this into the $shape object that tangent has referenced?

      If @coords is created as: 
      @coords = ([$x1, $y1], [$x2, $y2], [$x3, $y3], ....);

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      then it's just a matter of doing: 
      $shape = \@coords;

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      Cheers,
      Rob
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[d/l]
[select]
      If just one array of (x1,y1,x2,y2...) the easiest way would be to use List::Util 
      use List::Util qw(pairmap);

my @coords = (86.925, 27.988, 86.5278, 27.744, 86.43, 27.365);

my @pairs = pairmap { [ $a, $b ] } @coords;

$shp_writer->add_shape( \@pairs, @attributes );

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[d/l]

        tangent, thank you, that makes perfect sense. I have tried the following code and am now getting an error regarding "Can't use string ("0") as an ARRAY ref while "strict refs" in use at <path to writer.pm> line 141". I have tried adding the use strict; and declaring $x/$y/$dummy, but did not help.
        The following code is what I am using to try to get it to work:

        use Geo::Shapefile::Writer;
use List::Util qw(pairmap);

$shape = Geo::Shapefile::Writer->new("Temp", 'POLYGON', [COL1 => 'C', 
+10],);
my @coords = (0, 0, 0, 1, 1, 1, 1, 0, 0, 0);
my @pairs = pairmap { [ $a, $b ] } @coords;

# Checking to make sure pairs look correct
foreach $dummy (@pairs)
{
  ($x, $y) = @$dummy;
  print "$x, $y\n";
}

$shape->add_shape(\@pairs, {Col1 => "Dumb1"});
$shape->finalize();

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[reply]
[d/l]

      I'm sorry I can't say more without knowing more about the format of the shapefiles which I don't have the time to look into at the moment, but it looks like your @coords array will have to be a part of the "add_shape" subroutines argument somehow. I have dealt with shapefiles long ago and I remember it was ugly. You probably have shapefile help around, but here is a link that I would have to start with.

      -Tom

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