I have two files. A 'sequence' file, which looks like this. 
>ONE
IRLA
>TWO
REFT
>THREE
HTED

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and a set of correponding 'co-ordinate' files. The name of the co-ordinate file that corresponds to a particular sequence in the sequence file is highlighted by '>' a line above the actual sequence. Each of these files is made up of entries. Each entry is numbered. Some co-ordinate files start with entry number 1 but not all. The one below (the co-ordinate file named 'ONE'), for example, starts with an entry numbered 12. 
12      14.620  35.834 -16.759  1.00 11.04            
13      15.922  36.983 -19.044  1.00 11.22            
14      14.326  37.148 -21.240  1.00 11.40             
15      11.528  38.248 -23.343  1.00 12.44

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This corresponds to the first sequence in the sequence file 
IRLA

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I need to assign each letter in that sequence with the corresponding entry in the corresponding co-ordinate file. You read the sequence file from left to right with each letter needing to be mapped to an numbered entry in the co-ordinate file. So .. for the first letter 'R' in the sequence, it has to be mapped to entry number 13 in the co-ordinate file - the second letter in the sequence 'R', it corresponds to the second entry in the co-ordinate file, which in this case is entry 13. The resulting text file should look like this 
I 12
R 13
L 14
A 15

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I'm not sure what the best way of going about writing a perl script for this is. Any advice/hints much appreciated. The real examples are obviously far larger than the test case presented here

In reply to mapping data between files by Angharad

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