Import TRMM - Revision history

Neteler: /* Getting rotated maps in TRMM-HDF? */

2014-09-25T09:06:13Z

Getting rotated maps in TRMM-HDF?

← Older revision		Revision as of 09:06, 25 September 2014
Line 28:		Line 28:
	These are rotated and need to be rotated back. The (properly oriented) binary grids are much easier to handle than the original HDF files.		These are rotated and need to be rotated back. The (properly oriented) binary grids are much easier to handle than the original HDF files.

	See also ~~{{AddonCmd\|~~r.flip~~\|version=7}}~~		See also [[AddOns/GRASS7/raster#r.flip]]

	[[Category: FAQ]]		[[Category: FAQ]]
	[[Category: Import]]		[[Category: Import]]

Neteler: /* Getting rotated maps in TRMM-HDF? */

2012-12-20T14:52:52Z

Getting rotated maps in TRMM-HDF?

← Older revision		Revision as of 14:52, 20 December 2012
Line 27:		Line 27:

	These are rotated and need to be rotated back. The (properly oriented) binary grids are much easier to handle than the original HDF files.		These are rotated and need to be rotated back. The (properly oriented) binary grids are much easier to handle than the original HDF files.

			See also {{AddonCmd\|r.flip\|version=7}}

	[[Category: FAQ]]		[[Category: FAQ]]
			[[Category: Import]]

⚠️Vesnikos: small typo

2010-11-17T21:21:27Z

small typo

← Older revision		Revision as of 21:21, 17 November 2010
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	north=50 south=-50 east=180 west=-180 rows=400 cols=1440		north=50 south=-50 east=180 west=-180 rows=400 cols=1440

	Optionally convert then to mm/hr to some other time unit.		Optionally convert then from mm/hr to some other time unit.

	=== Getting rotated maps in TRMM-HDF? ===		=== Getting rotated maps in TRMM-HDF? ===

Neteler: added rotation trick from Markus Metz

2010-11-17T11:54:09Z

added rotation trick from Markus Metz

← Older revision		Revision as of 11:54, 17 November 2010
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	TRMM data are usually delivered in a specific HDF format which is (partially) supported from GDAL 1.8+ (so, {{cmd\|r.in.gdal}} would in theory work).		TRMM data are usually delivered in a specific HDF format which is (partially) supported from GDAL 1.8+ (so, {{cmd\|r.in.gdal}} would in theory work, see also below for rotation problem).

	However, it is easier to get binary grids from here		However, it is easier to get instead binary grids from here:

	ftp://disc2.nascom.nasa.gov/data/TRMM/Gridded/3B43_V6/		ftp://disc2.nascom.nasa.gov/data/TRMM/Gridded/3B43_V6/
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	Optionally convert then to mm/hr to some other time unit.		Optionally convert then to mm/hr to some other time unit.

			=== Getting rotated maps in TRMM-HDF? ===

			The TRMM 3B43 HDF files are rotated by 90° (clockwise), so north is right and west is up. The included datasets "precipitation" and "error" can be dumped from the HDF files to a binary or ASCII file with the "hdp" tool which should be on any system that has the HDF4 library installed.

			Rotate "precipitation" with
			hdp dumpsds -r 4 -d -o <outfile> -b <TRMM_3B43.hdf>

			and "error" with
			hdp dumpsds -r 5 -d -o <outfile> -b <TRMM_3B43.hdf>

			These are rotated and need to be rotated back. The (properly oriented) binary grids are much easier to handle than the original HDF files.

	[[Category: FAQ]]		[[Category: FAQ]]

Neteler: new, based on comments from Markus Metz

2010-11-17T09:43:24Z

new, based on comments from Markus Metz

New page

TRMM data are usually delivered in a specific HDF format which is (partially) supported from GDAL 1.8+ (so, {{cmd|r.in.gdal}} would in theory work).

However, it is easier to get binary grids from here

ftp://disc2.nascom.nasa.gov/data/TRMM/Gridded/3B43_V6/

The format is explained [ftp://disc2.nascom.nasa.gov/data/TRMM/Gridded/3B43_V6/3B43.ctl here]. Hence, to import gridded TRMM into a Lat-long location with is done via

# generally
r.in.bin -f -b north=50 south=-50 east=180 west=-180 rows=400 cols=1440 ....

e.g.
r.in.bin -f -b input=3B43.100101.6.precipitation.bin output=3B43.100101.6.precipitation \
north=50 south=-50 east=180 west=-180 rows=400 cols=1440

Optionally convert then to mm/hr to some other time unit.

[[Category: FAQ]]