Hi, I have a lot of rasters in ESRI ASCII raster format (text files). These can be added to ArcMap by simply dragging them from ArcCatalog. I use ArcGIS desktop 9.3.1 SP2.
The problem is: These rasters contain FLOAT data, but when directly opened in ArcMap they are displayed as INTEGER grids. Here is an example of a header + first line w/ nodata values: ncols 2410 nrows 1220 xllcorner 21000 yllcorner 128000 cellsize 100 NODATA_value -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 -9999 etc.
I've noticed that the rasters will only display data with real values, instead of integer, if: 1) the decimal separator is a point (instead of a comma) 2) the first value in the raster after the header includes a decimal point e.g. -9999.0 instead of -9999
Almost all of my rasters start with a nodata value of -9999, so I'd have to put '.0' behind every first value in the ASCII files or I'd have to import all the ASCII files to rasters using e.g. RasterToASCII_conversion.
Is there another way to visualise these rasters directly and correctly without the need to change all my ascii files as described above? Is there another text file format for rasters that could perform better than the ESRI ASCII format?