algorithm - Does the order of data in a text file affects its compression ratio? -



algorithm - Does the order of data in a text file affects its compression ratio? -

i have 2 big text files (csv, precise). both have exact same content except rows in 1 file in 1 order , rows in other file in different order.

when compress these 2 files (programmatically, using dotnetzip) notice 1 of files considerably bigger -for example, 1 file ~7 mb bigger compared other.-

my questions are:

how order of info in text file impact compression , measures can 1 take in order guarantee best compression ratio? - presume having similar rows grouped (at to the lowest degree in case of zip files, using) help compression not familiar internals of different compression algorithms , i'd appreciate quick explanation on subject.

which algorithm handles sort of scenario improve in sense accomplish best average compression regardless of order of data?

"how" has been answered. reply "which" question:

the larger window matching, less sensitive algorithm order. compression algorithms sensitive degree.

gzip has 32k window, bzip2 900k window, , xz 8mb window. xz can go 64mb window. xz to the lowest degree sensitive order. matches farther away take more bits code, improve compression with, example, sorted records, regardless of window size. short windows preclude distant matches.

algorithm compression zip

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