floating point option for USGSDEM

[mdunn]

Please include FP in addition to the default integer as option for USGSDEM format.

Thanks! Mike

[warmerdam]

The USGSDEM driver supports reading floating point files, but does not support writing them. It would be desirable to support writing them as well, though to be honest this is not very high on my priority list.

[Jukka Rahkonen]

There is this creation option:

ZRESOLUTION=float: DEM's store elevation information as positive integers, and these integers are scaled using the "z resolution." By default, this resolution is written as 1.0. However, you may specify a different resolution here, if you would like your integers to be scaled into floating point numbers.

It feels to me that this option fulfills the need.