WWLLN Relative Detection Efficiency maps are generated with the matlab routine
de_mapper.m written by Michael Hutchins (mlhutch@uw.edu). Below is a
description of the variables in each DE.mat file.

Note: all the DE data files are now open to the public at
http://wwlln.net/deMaps/


de_map - relative detection efficiency map in 5, 2, or 1 degree bins
(depending on creation date)
de_map_high - de_map that has been smoothed to 1˚ resolution
de_time - time of the 24 maps in matlab datenum format

The de_map file are centered so that the first entry, de_map(1,1,1), gives the
detection efficiency for the bin that spans -180˚ E to -175˚ E, 85˚N to 90˚N
for UTC hour 00:00 to 00:59.

The first index is increasing longitude (1 = -180 to -175, 2 = -175 to -170,
etc) , the second index is decreasing latitude (1 = 90 to 85, 2 = 85 to 80,
etc) and the third index is the UTC hour plus one (1 = 00:00 to 00:59, 2 =
01:00 to 01:59, etc). 

The deMaps are also stored as compressed text files with the suffix .dat.gz.
Each line in the text file corresponds to a different longitudinal slice of
the deMap with each entry corresponding to a latitude bin at that longitude.
The indexing starts at -180 E longitude and -90 N latitude.  The data are tab
separated, a line by line tab delimited import will result in a 8640 x 180
element array, with every 360 rows corresponding to a successive hour.

For example with an imported 8640 x 180 element array:

	Elements [1:360, 1:180] give the relative detection efficiency map for 0
UTC, elements [361:720, 1:180] give the map for 1 UTC etc.
	Within the 0 UTC map, elements [1, 1:180] give the latitude entries -90 to -89, -89 to -88, ... 89 to 90 for the -180 to -179 degrees E longitude slice.

Note: there is an empty line between each hour, so the plaintext files have
8664 lines (8640 + 24 hour separation lines).