On Unix a simple alternative to perl is to use the system's sort command: 

% sort -uk 1,1 datafile > sorted_datafile

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That will sort strictly (i.e. no duplicates) on the first field; the first instance encountered is the one kept. See man sort (or info sort if your system uses GNU's sort).

the lowliest monk

In reply to Re: sorting arrays by tlm
in thread sorting arrays by Anonymous Monk

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