Changes between Version 3 and Version 4 of Processing/NextMapDEMs


Ignore:
Timestamp:
Nov 29, 2007, 11:12:43 AM (16 years ago)
Author:
benj
Comment:

Added procedure for patching in sea-level area for sea areas with no OS data

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  • Processing/NextMapDEMs

    v3 v4  
    4747r.out.ascii input=tl17and27 output=/tmp/tl17and27.dem null=0
    4848}}}
     49
     50---------
     51To add a zero-level area to a map (ie sea level):
     52
     53In GRASS:
     54{{{
     55# Restrict active region to area you're interested in - must use eastings/northings, lat/long seems to have problems determining valid values
     56g.region n=601000 e=451000 s=579000 w=389000
     57
     58# Check region is restricted correctly
     59g.region -gb
     60
     61# Create vector map of active region, output param is name of output map
     62v.in.region output=v_sealevel
     63
     64# Convert vector map to raster map
     65v.to.rast input=v_sealevel output=r_sealevel use=val value=0.0
     66
     67# Create raster maps for areas with OS data as first line only in section above
     68r.in.gdal -e input=/data/aegean1/nextmap_dems/neodc/by_tile/by_product/dsm/ny/ny98/ny98dsm/w001001.adf output=ny98
     69r.in.gdal -e input=/data/aegean1/nextmap_dems/neodc/by_tile/by_product/dsm/ny/ny99/ny99dsm/w001001.adf output=ny99
     70...
     71
     72# Patch raster maps together as section above
     73# NOTE SEA LEVEL MAP MUST BE LAST IN LIST, since Grass starts with a blank map and adds patched raster maps in order
     74r.patch input=ny98,ny99,...,r_sealevel output=map_with_added_sea_level
     75
     76# Create DEM from raster map as section above
     77r.out.ascii input=map_with_added_sea_level output=/tmp/map_with_added_sea_level.dem null=0
     78}}}