Difference between revisions of "Tarsier: Raster data"
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− | As the name implies, a Tarsier Raster Data file (.tra) is Tarsier's gridded data format. It is made up of two parts: 1) an ASCII header file that specifies the structure of the grid and data properties, and 2) a series of data values stored | + | As the name implies, a Tarsier Raster Data file (.tra) is Tarsier's gridded data format. It is made up of two parts: 1) an ASCII header file that specifies the structure of the grid and data properties, and 2) a series of data values stored as binary numbers. |
A typical Tarsier header looks like: | A typical Tarsier header looks like: | ||
Line 10: | Line 10: | ||
CellHeight 1 | CellHeight 1 | ||
NoDataValue -9999.000000 | NoDataValue -9999.000000 | ||
− | Projection | + | Projection latlon |
Precision float | Precision float | ||
Format binary | Format binary | ||
* | * | ||
− | + | This raster is a 25 X 25 pixel lat/long grid with the lower left corner located at the intersection of the prime meridian and the equator. The resolution is 1 degree. Data points are stored as floating point numbers (can include signed decimals) and the value -9999 represents no data. | |
+ | |||
+ | The size of the raster is limited by the memory of your machine, but most modern computers can easily handle raster up to 49,000,000 pixles (7,000 x 7,000). | ||
+ | |||
+ | Tarsino likes UTM grids, but other projections are also supported: | ||
+ | -add table of projections- | ||
− | |||
==Learn more about rasters and how to work with .tra files== | ==Learn more about rasters and how to work with .tra files== | ||
Take the [[Tarsier tutorial: Raster data | Tarsier tutorial for Raster data]]. | Take the [[Tarsier tutorial: Raster data | Tarsier tutorial for Raster data]]. |
Revision as of 10:40, 28 February 2009
As the name implies, a Tarsier Raster Data file (.tra) is Tarsier's gridded data format. It is made up of two parts: 1) an ASCII header file that specifies the structure of the grid and data properties, and 2) a series of data values stored as binary numbers.
A typical Tarsier header looks like:
Cols 25 Rows 25 XLLCorner 0 YLLCorner 0 CellWidth 1 CellHeight 1 NoDataValue -9999.000000 Projection latlon Precision float Format binary *
This raster is a 25 X 25 pixel lat/long grid with the lower left corner located at the intersection of the prime meridian and the equator. The resolution is 1 degree. Data points are stored as floating point numbers (can include signed decimals) and the value -9999 represents no data.
The size of the raster is limited by the memory of your machine, but most modern computers can easily handle raster up to 49,000,000 pixles (7,000 x 7,000).
Tarsino likes UTM grids, but other projections are also supported: -add table of projections-
Learn more about rasters and how to work with .tra files
Take the Tarsier tutorial for Raster data.