lddmask

lddmask

Local drain direction map cut into a (smaller) sound local drain direction map

Result = lddmask(ldd, mask)

ldd

spatial ldd

mask

spatial boolean

Result

spatial ldd

Operation

The cell values on mask are interpreted as boolean values, where 1 is TRUE and 0 is FALSE. The part of the local drain direction map ldd which you want to cut out must totally be filled with 1 (TRUE) values on mask.

Each cell with a mask value 0 (FALSE) is assigned a missing value on Result. Each cell with a mask value 1 (TRUE) is assigned a value which corresponds with the value on ldd, except cells with a mask value 1 that have a local drain direction on ldd towards a cell with a 0 (FALSE) on mask. These last named cells are outflow cells on the edge of the new ldd, these are assigned a cell value 5, which is the ldd code for a pit.

Notes

A cell with a missing value on mask is interpreted as a mask value 0 (FALSE) and handled in that way. In addition, a cell with a missing value on ldd is assigned a missing value on Result.

Group

This operation belongs to the group of Missing value creation

See Also

Operations with local drain direction maps

Examples

1. • pcrcalc

   binding

   Result = Result.map;

   Ldd = Ldd.map;

   Mask = Mask.map;

   initial

   report Result = lddmask(Ldd,Mask);

   
   

   • python

   Ldd = readmap(“Ldd.map”)

   Mask = readmap(“Mask.map”)

   Result = lddmask(Ldd,Mask)

   Result.map	Ldd.map	Mask.map