I downloaded the GPWv3 Population Density .ascii format. I'm having trouble parsing this data correctly. I read in the meta data at the top of the file (lower-left latitude/longitude origin of the grid, cell size, etc) and these seem to make sense. But when I plot all cells with a density greater than 300, the points are not syncing up with the map (i.e. I'm seeing large blobs of population in the Pacific). Am I correct in assuming that the rows of the file begin at the lower-left point given, with the columns representing increasing longitude and rows representing increasing latitude?

It is correct to assume that the lower-left corner of the grid is -180,-58 and that there are 3432 rows and 8640 cols.

When parsing the data as in table below, the first cell below the NODATA_value (-9999) should be placed at the top-left corner of the output raster (-180, 85).

ncols         8640
nrows         3432
xllcorner     -180
yllcorner     -58
cellsize      0.0416666666667
NODATA_value  -9999
-9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 .....

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