A FASTQ file contains four details for each read in the following format:
Sequence identifier and/or a description
Sequence letters
+ and/or repeat of line 1 details
Encoding of line 2 with the same amount of letters/characters
Line 4 provides the quality of the sequence in line 2 using a 21 character code, where each symbol stands for a certain level of quality. The code is provided below, with the “!” representing the lowest quality and “~” representing the highest.
!"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~
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