[GRASS-dev] Re: Fix for gis.m profile dialog division by zero

[Michael Barton]

OK. If it's for foolproofing, then the error trap is perfect. I just wanted
to make sure that there was no new systematic problem with elevation ranges
on a valid map to profile.

Michael


On 2/11/07 11:30 AM, "Maris Nartiss" <maris.gis at gmail.com> wrote:

> Hi Michael,
> 
> it will divide by zero on any non-normal map - think of binary map (1,null).
> It has no sense for such maps to create profiles, but it does not mean
> that gis.m should fail if user is dumb. It's one of my thisweekends
> efforts to make gis.m foolproof. :)
> 
> Maris.
> 
> 2007/2/11, Michael Barton <michael.barton at asu.edu>:
>> Maris,
>> 
>> Do you know what is making this divide by 0 and under what circumstances
>> (e.g., range of elevation values on map, location/projection
>> characteristics)? On my system, with a build of 2 days ago, the profiling
>> works fine with the "normal" map of the Spearfish 30m DEM.
>> 
>> This happened a couple times before when the GRASS module used for
>> calculating the total elevation range was giving incorrect information in
>> certain circumstances and when there were changes in the function of
>> g.region flags. It was an example of the cascade of effects that can happen
>> if a module function is changed in seemingly minor ways.
>> 
>> The error trapping is a good idea in any case. But I want to make sure we
>> also understand the cause rather than just treat the symptoms.
>> 
>> Michael
>> 
>> 
>> On 2/10/07 12:30 PM, "grass-codepatches at wald.intevation.org"
>> <grass-codepatches at wald.intevation.org> wrote:
>> 
>>> code patches item #281, was opened at 2007-02-10 21:30
>>> Status: Open
>>> Priority: 3
>>> Submitted By: M?ris Nartišs (marisn)
>>> Assigned to: Nobody (None)
>>> Summary: Fix for gis.m profile dialog division by zero
>>> Patch status: None
>>> Patch type: fix
>>> GRASS component: gis.m
>>> GRASS version: CVS HEAD
>>> GRASS CVS checkout date, if applies (YYMMDD): 070210
>>> 
>>> 
>>> Initial Comment:
>>> This patch prevents gis.m profile tool from dividing by zero and makes
>> popup
>>> windows to appear on top of profile window and not gis.m main window.
>>> 
>>> ----------------------------------------------------------------------
>>> 
>>> You can respond by visiting:
>>> 
>> http://wald.intevation.org/tracker/?func=detail&atid=205&aid=281&group_id=21
>>> 
>>> 
>> 
>> __________________________________________
>> Michael Barton, Professor of Anthropology
>> School of Human Evolution & Social Change
>> Center for Social Dynamics & Complexity
>> Arizona State University
>> 
>> phone: 480-965-6213
>> fax: 480-965-7671
>> www: http://www.public.asu.edu/~cmbarton
>> 
>> 
>> 
> 
> 

__________________________________________
Michael Barton, Professor of Anthropology
School of Human Evolution & Social Change
Center for Social Dynamics & Complexity
Arizona State University

phone: 480-965-6213
fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton