[GRASS-dev] i.points, i.vpoints now use G_parser()

[Michael Barton]

> From: Glynn Clements <glynn at gclements.plus.com>
> Date: Mon, 26 Jun 2006 12:16:18 +0100
> To: Michael Barton <michael.barton at asu.edu>
> Cc: Hamish <hamish_nospam at yahoo.com>, grass5 <grass-dev at grass.itc.it>
> Subject: Re: [GRASS-dev] i.points, i.vpoints now use G_parser()
> 
> That's easy enough to generate. Do you need the disabled points as
> well? Currently, the errors are only being computed for valid points.
> 
> Presumably disabled points shouldn't be included in the RMS error,
> even if the individual errors are being displayed.
> 


The easiest to parse would be distance for each point. Calculating RMS is
pretty easy to do in TclTk if I have the projected disances.

Thinking about it, I all I really need is "g". I can put "g" in the proper
spot in the GCP management form and already have an algorithm to calculate
RMS for valid points only (sqrt(sumsq(g)/N)).

Probably the simplest would be for me to run g.transform each time the user
does a 'save' of points. This would recalculate g and total RMS.

How does that sound?

>> Sorry for being dense, but does it return a string that includes newlines
>> like the following...
>> 
>> "Number of active points: 5\nForward:\nx = 999999.999\ny = 9999999.999\n..."
>> 
>> ...or just the values like the following...
>> 
>> "5 999999.999 9999999.999..."
> 
> The format should be exactly as described above, except with the
> %d/%.2f specifiers replaced with actual values.
> 
> I can change the format to whatever is easiest to process.

After all that, it is sounding like the best way to go is simply to return a
string with the 'g' values separated by something easy to cut--newlines,
colons, etc.

Michael


__________________________________________
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