Doesn't look too complicated. Modify to your needs:

use 5.16.2;
use warnings;

use Data::Peek;
use Text::CSV_XS qw( csv );

my $extra = csv (in => \<<"EOC", headers => "auto");
LocnID,Lat,Lon,TestCo#,LastVol,LocnName,LocnAdr
291061000,5140598,645573,205,3568,Evans Marcross,
250401500,5141451,647444,205,857,Thomas And Ptns Somerset,
250400800,5147664,656137,205,1727,Thomas J  Newton House,
EOC

my $base = csv (in => \<<"EOC", key => "Seq#");
Seq#,TransType,LocnNum,TankNum,Date,TimeStart,TimeEnd,TktVol,AltVol,To
+talSrt,TotalEnd,Driver,Trip,Route,MeanDegC,MaxDegC,ColCd,Ccode,TestTy
+pe,TrpSdate,GPSlat,GPSlon
174,0,291061000,59,141130,104945,105755,3355,0,255094551,255094551,500
+5,2,505,3.0,3.5,00,00,00,141130,5140596,645572
175,0,250401500,133,141130,110343,110858,760,0,255102140,255102140,500
+5,2,505,3.0,3.2,00,00,00,141130,5141449,647452
176,0,250400800,29,141130,115529,120130,1695,0,255119079,255119079,500
+5,2,505,3.7,4.2,00,00,00,141130,5147668,656139
EOC

foreach my $seq (sort keys %$base) {
    my @extra =  grep { abs ($_->{Lat} - $base->{$seq}{GPSlat}) < 10 &
+&
                        abs ($_->{Lon} - $base->{$seq}{GPSlon}) < 10 }
+ @$extra;
    @extra > 1 and warn "Multiple matches!\n";
    my $ref = $extra[0] // { Lat => 0, Lon => 0, LocnName => "?" };
    printf "%5d %10d %10d %10d %10d %s\n", $seq,
        $base->{$seq}{GPSlat}, $base->{$seq}{GPSlon},
        $ref->{Lat}, $ref->{Lon}, $ref->{LocnName};
    }

=>

  174    5140596     645572    5140598     645573 Evans Marcross
  175    5141449     647452    5141451     647444 Thomas And Ptns Some
+rset
  176    5147668     656139    5147664     656137 Thomas J  Newton Hou
+se

[download]

Of course you can write a sub that finds the closest match and return the extra information. You could also hang that sub on a callback for on_in in the csv (on_in => \&foo), but that is completely up to you.


Enjoy, Have FUN! H.Merijn

In reply to Re: CSV Cross Referencing by Tux
in thread CSV Cross Referencing by Jalcock501

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