convert csv containing lon,lat,name files into geojson

csv2geojson.perl

#!/usr/bin/perl -w
# see http://newtoypia.blogspot.tw/2015/07/csv-geojson.html

$prev = 0;	# was there any previous output?
print "[\n";
while (<>) {
    chomp;
    next if (/^#/ or /^\s*$/);
    @f = split /\s*,\s*/;
    if (defined($F{lon}) and defined($F{lat})) {
	print ",\n" if $prev;
	@prop = ();
	print qq({"type":"Feature", "geometry":{ "type":"Point","coordinates":[$f[$F{lon}],$f[$F{lat}]]}, "properties":{);
	for ($i=0; $i<=$#f; ++$i) {
	    next if ($i==$F{lon} or $i==$F{lat});
	    push @prop, qq("$keys[$i]": "$f[$i]");
	}
	print join(',', @prop);
	print qq(}});
	$prev = 1;
    } elsif (/\blon(gitude)?\b/i and /\blat(itude)?\b/i) {
	# @f : index => key
	for ($i=0; $i<=$#f; ++$i) {
	    $f[$i] = "lon" if $f[$i] =~ /\blon(gitude)?\b/i;
	    $f[$i] = "lat" if $f[$i] =~ /\blat(itude)?\b/i;
	    $F{$f[$i]} = $i;
	}
	# %F : key => index
	die unless (defined($F{lon}) and defined($F{lat}));
	@keys = @f;
    }
}
print "\n]\n\n";