r.mapcalc

[Precision Farming Project]

Hello GRASS programmers.  A couple of questions and/or
comments looking for input about r.mapcalc
(which I can't seem to find documented in the man pages).
(I am trying to tidy up a r.mapcalc program which uses
8 temporary raster layers to calculate a single raster
which is a function of 3 raster layers.  Seems just a tad
wasteful).

I gather that all variable names in a mapcalc "program"
refer to raster maps (there are no scalar variables).

With respect to the modulus operator (%), I am expecting
that the divisor must be an integer (or do both
operands need to be integer?).

Can logical operators be used in arithmetic statements?
( x = y * 3 && (z > 1.0) )?

There isn't by chance an else operator?  Any kind of logical
flow control?

aTdHvAaNnKcSe

Gordon Haverland
goddard at gpu.ualberta.ca
ghaverla at freenet.edmonton.ab.ca