[GRASS-user] Need help with figuring out how to use category values and labels with r.statistics

[William Hudspeth]

Hello,

I am having a bit of a problem figuring out how to solve a processing
flow:

I am starting out with a raster with a continuous distribution of float
values. I want to calculate some basic descriptive statistics using
r.statistics, but do not want to lose the important numeric information
following the decimal point in the cell values. Because r.statistics
only works on integer raster maps, I have first multiplied the float
maps by a constant (e.g. 10,000), with the hopes that I can later divide
by that constant to retain the figures following the decimal point.

e.g.

r.mapcalc integer_map=int(float_map*10000)

I have a raster map of state county id numbers that I use in the
r.statistics calculation - the aim is to generate basic summary stats
(e.g. mean) for each county

e.g.

r.statistics base=county_ids cover=integer_map output=mean_by_county
method=average

The output map has category values set to the county IDs, and category
labels set to the means by county (multiplied by the constant 10000). So
far, so good.

To get back to a mean of the original values, I would like to divide
these output maps by the constant (10000.00) using r.mapcalc, but doing
so yields the category values (county IDs) divided by 10000, with empty
category labels (losing the statistical information). If I use the -c
argument in r.statistics (which uses the category labels in the
calculation), I end up with the correct category labels (county IDs),
but I will have lost all of the statistical information.

How do I get back to my original values (dividing by the constant of
10000) without losing the county id category labels with which they are
associated?

Thanks, Bill