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1The 155 input files nearly form a 13x12 grid, missing just the file that would otherwise occupy the southwest corner of the grid.
2The input files corresponding to the westmost blocks are 1 pixel (30") narrower, i.e. 119 x 120 pixels, 0°59'30" x 1° coverage.
3The intermediate files corresponding to the westmost strips are 1 pixel (30") narrower and 120 pixels (1°) shorter than the other strips, i.e. 119 x 1320 pixels, 0°59'30" x 11° coverage.
4The westmost 1-pixel (30") wide column in each output file does not correspond to data in any input file. Nor does the southwest-most 120 x 120 pixel (1° x 1°) block in each file.
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