[GRASS-dev] area measurements
Hello dear devs, I am wondering if something happened since this 4 year old ticket, where the question of area measurements was raised : http://trac.osgeo.org/grass/ticket/975 When I need to get an area on the fly, I run d.measure on a graphic monitor, but it would be very nice to access this function straightly from wxGUI. Using 6.4 for my workflow, perhaps I missed something on the 7.0 side ? Thank you, and best wishes for New Year's Eve ;-) Vincent. ___ grass-dev mailing list grass-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-dev
Re: [GRASS-dev] area measurements
On Sat, Dec 28, 2013 at 3:28 PM, Vincent Bain wrote: > Hello dear devs, > > I am wondering if something happened since this 4 year old ticket, where > the question of area measurements was raised : > > http://trac.osgeo.org/grass/ticket/975 > > When I need to get an area on the fly, I run d.measure on a graphic > monitor, but it would be very nice to access this function straightly > from wxGUI. Using 6.4 for my workflow, perhaps I missed something on the > 7.0 side ? In the ticket m.measure is suggested as solution which accepts a series of coordinates to then perform the calculation: http://grass.osgeo.org/grass70/manuals/m.measure.html Perhaps, given that a new tiny digitizer is there for wxGUI-i.class etc, perhaps this could be used to call m.measure then? > Thank you, and best wishes for New Year's Eve ;-) Thanks & best wishes from here, Markus ___ grass-dev mailing list grass-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-dev
Re: [GRASS-dev] area measurements
Hi all, I added support for area measurement in wxGUI (the same place as measuring distance). You are welcome to test. However, I have a few questions/problems: I was wondering if module m.measure requires a series of coordinates with or without repeating the first pair of coordinates. This is suggested by the fact that it requires at least 4 points for measuring area. If I suppress this condition and use only 3 points it gives me the right result, too. This is probably given by the underlying functions G_area_of_polygon, but I haven't found anything in the documentation. I would be glad if we can write something in the m.measure manual because the user might be surprised not to get area for 3 points. The second thing is about projection. For this projection: name=Lambert Conformal Conic proj=lcc datum=nad83 a=6378137.0 es=0.006694380022900787 lat_1=34.34 lat_2=36.16 lat_0=33.75 lon_0=-79 x_0=609601.219997 y_0=0 no_defs=defined unit=Foot_US units=Foot_USs meters=0.3048006096012192 I get nothing from m.measure. I can create a ticket if necessary. Best, Anna On Mon, Dec 30, 2013 at 7:50 AM, Markus Neteler wrote: > On Sat, Dec 28, 2013 at 3:28 PM, Vincent Bain wrote: > > Hello dear devs, > > > > I am wondering if something happened since this 4 year old ticket, where > > the question of area measurements was raised : > > > > http://trac.osgeo.org/grass/ticket/975 > > > > When I need to get an area on the fly, I run d.measure on a graphic > > monitor, but it would be very nice to access this function straightly > > from wxGUI. Using 6.4 for my workflow, perhaps I missed something on the > > 7.0 side ? > > In the ticket m.measure is suggested as solution which accepts a > series of coordinates to then perform the calculation: > http://grass.osgeo.org/grass70/manuals/m.measure.html > > Perhaps, given that a new tiny digitizer is there for wxGUI-i.class > etc, perhaps this could be used to call m.measure then? > > > Thank you, and best wishes for New Year's Eve ;-) > > Thanks & best wishes from here, > Markus > ___ > grass-dev mailing list > grass-dev@lists.osgeo.org > http://lists.osgeo.org/mailman/listinfo/grass-dev > ___ grass-dev mailing list grass-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-dev
Re: [GRASS-dev] area measurements
Hi Anna, I just tested on r58611. Unfortunately it fails : when prompted to click and drag first segment, it looks like it works but then it's impossible to click a third point. I need to kill once m.measure process, then a second m.measure process initiates, which I have to kill again. After both are killed, I get the following message on the console : > Measuring area: > > Units not recognized, measurement failed. > > Area: 0 > > Units not recognized, measurement failed. > > Area: 0 and the display refreshes. Here's my g.proj -g name=Lambert Conformal Conic proj=lcc ellps=clark80IGN lat_1=46.8 lat_0=46.8 lon_0=0 k_0=0.99987742 x_0=60 y_0=220 towgs84=-168,-60,320,0,0,0,0 pm=paris no_defs=defined nadgrids=ntf_r93.gsb,null unit=metre units=metres meters=1 On the other hand, measuring distances works like a charm... Best, Vincent. ___ grass-dev mailing list grass-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-dev
Re: [GRASS-dev] area measurements
Vincent, On Sun, Jan 5, 2014 at 5:19 AM, Vincent Bain wrote: > Hi Anna, > > I just tested on r58611. Unfortunately it fails : > could you try m.measure separately? Launch it from gui command line or menu so that you have the interactive adding coordinates from map display. Could you post the result of m.measure with and without -g flag? Thanks, Anna > when prompted to click and drag first segment, it looks like it works > but then it's impossible to click a third point. > > I need to kill once m.measure process, then a second m.measure process > initiates, which I have to kill again. After both are killed, I get the > following message on the console : > > > Measuring area: > > Units not recognized, measurement failed. > > Area: 0 > > Units not recognized, measurement failed. > > Area: 0 > > and the display refreshes. > > Here's my g.proj -g > > name=Lambert Conformal Conic > proj=lcc > ellps=clark80IGN > lat_1=46.8 > lat_0=46.8 > lon_0=0 > k_0=0.99987742 > x_0=60 > y_0=220 > towgs84=-168,-60,320,0,0,0,0 > pm=paris > no_defs=defined > nadgrids=ntf_r93.gsb,null > unit=metre > units=metres > meters=1 > > On the other hand, measuring distances works like a charm... > > Best, > Vincent. > > ___ grass-dev mailing list grass-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-dev
Re: [GRASS-dev] area measurements
Le dimanche 05 janvier 2014 à 08:42 -0500, Anna Petrášová a écrit : > > Vincent, > > On Sun, Jan 5, 2014 at 5:19 AM, Vincent Bain wrote: > Hi Anna, > > I just tested on r58611. Unfortunately it fails : > > > could you try m.measure separately? Launch it from gui command line or > menu so that you have the interactive adding coordinates from map > display. Could you post the result of m.measure with and without -g > flag? Yes, here it is with four points describing a 1 km side square : m.measure coordinates=922000,2106000,923000,2106000,923000,2107000,922000,2107000 units=meters Length: 3000.00 meters Area:100.00 square meters m.measure -g coordinates=922000,2106000,923000,2106000,923000,2107000,922000,2107000 units=meters units=meters,square meters length=3000.00 area=100.00 Having a closer look at my PROJ_UNITS file, I noticed unit was set to "metre" and units was set to "metres". I tried to change these values to "meter" and "meters". And now it works just fine. I can't say when and how one can tweak this variable. Do you think this enhancement could be easily backported to 6.4 ? Yours, V. ___ grass-dev mailing list grass-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-dev
Re: [GRASS-dev] area measurements
Hi Vincent, On Sun, Jan 5, 2014 at 10:14 AM, Vincent Bain wrote: > Le dimanche 05 janvier 2014 à 08:42 -0500, Anna Petrášová a écrit : > > > > Vincent, > > > > On Sun, Jan 5, 2014 at 5:19 AM, Vincent Bain wrote: > > Hi Anna, > > > > I just tested on r58611. Unfortunately it fails : > > > > > > could you try m.measure separately? Launch it from gui command line or > > menu so that you have the interactive adding coordinates from map > > display. Could you post the result of m.measure with and without -g > > flag? > > Yes, here it is with four points describing a 1 km side square : > > m.measure > coordinates=922000,2106000,923000,2106000,923000,2107000,922000,2107000 > units=meters > Length: 3000.00 meters > Area:100.00 square meters > > m.measure -g > coordinates=922000,2106000,923000,2106000,923000,2107000,922000,2107000 > units=meters > units=meters,square meters > length=3000.00 > area=100.00 > > I actually didn't want you to use the units parameter, this is why you got reasonable outputs. Without it you would probably get segmentation fault. I created a ticket for this: http://trac.osgeo.org/grass/ticket/2157 Having a closer look at my PROJ_UNITS file, I noticed unit was set to > "metre" and units was set to "metres". I tried to change these values to > "meter" and "meters". And now it works just fine. > Yes, that makes sense. I was wondering why do you have metres instead of meters there? > I can't say when and how one can tweak this variable. > Do you think this enhancement could be easily backported to 6.4 ? > Unfortunately not. One thing is the GUI part which I would have to write again for grass 6 because although it looks the same, the code of wxGUI is quite different. And write it for grass 6 would be more difficult. The other thing is that m.measure is only a grass 7 module so I don't know which backend should be used for grass 6. Regards, Anna > Yours, > V. > > > ___ grass-dev mailing list grass-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-dev
Re: [GRASS-dev] area measurements
Hi Vincent, just FYI, I fixed (and Markus) the problems with units, so you should now be able to use 'metres' as well (but in GRASS 7 only). On Sun, Jan 5, 2014 at 4:05 PM, Anna Petrášová wrote: > Hi Vincent, > > > On Sun, Jan 5, 2014 at 10:14 AM, Vincent Bain wrote: > >> Le dimanche 05 janvier 2014 à 08:42 -0500, Anna Petrášová a écrit : >> > >> > Vincent, >> > >> > On Sun, Jan 5, 2014 at 5:19 AM, Vincent Bain wrote: >> > Hi Anna, >> > >> > I just tested on r58611. Unfortunately it fails : >> > >> > >> > could you try m.measure separately? Launch it from gui command line or >> > menu so that you have the interactive adding coordinates from map >> > display. Could you post the result of m.measure with and without -g >> > flag? >> >> Yes, here it is with four points describing a 1 km side square : >> >> m.measure >> coordinates=922000,2106000,923000,2106000,923000,2107000,922000,2107000 >> units=meters >> Length: 3000.00 meters >> Area:100.00 square meters >> >> m.measure -g >> coordinates=922000,2106000,923000,2106000,923000,2107000,922000,2107000 >> units=meters >> units=meters,square meters >> length=3000.00 >> area=100.00 >> >> I actually didn't want you to use the units parameter, this is why you > got reasonable outputs. Without it you would probably get segmentation > fault. I created a ticket for this: > http://trac.osgeo.org/grass/ticket/2157 > > Having a closer look at my PROJ_UNITS file, I noticed unit was set to >> "metre" and units was set to "metres". I tried to change these values to >> "meter" and "meters". And now it works just fine. >> > > Yes, that makes sense. I was wondering why do you have metres instead of > meters there? > > >> I can't say when and how one can tweak this variable. >> Do you think this enhancement could be easily backported to 6.4 ? >> > > Unfortunately not. One thing is the GUI part which I would have to write > again for grass 6 because although it looks the same, the code of wxGUI is > quite different. And write it for grass 6 would be more difficult. The > other thing is that m.measure is only a grass 7 module so I don't know > which backend should be used for grass 6. > > Regards, > Anna > > >> Yours, >> V. >> >> >> > ___ grass-dev mailing list grass-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-dev
Re: [GRASS-dev] area measurements
Thank you, Anna :) I just tested - it really works. Also I'm happy to see that event handling for distance measurement now is in a good shape. Finally both tools are usable in G7. Thank you and keep up your good work :) Maris. 2014/1/7 Anna Petrášová : > Hi Vincent, > > just FYI, I fixed (and Markus) the problems with units, so you should now be > able to use 'metres' as well (but in GRASS 7 only). > > > On Sun, Jan 5, 2014 at 4:05 PM, Anna Petrášová > wrote: >> >> Hi Vincent, >> >> >> On Sun, Jan 5, 2014 at 10:14 AM, Vincent Bain wrote: >>> >>> Le dimanche 05 janvier 2014 à 08:42 -0500, Anna Petrášová a écrit : >>> > >>> > Vincent, >>> > >>> > On Sun, Jan 5, 2014 at 5:19 AM, Vincent Bain wrote: >>> > Hi Anna, >>> > >>> > I just tested on r58611. Unfortunately it fails : >>> > >>> > >>> > could you try m.measure separately? Launch it from gui command line or >>> > menu so that you have the interactive adding coordinates from map >>> > display. Could you post the result of m.measure with and without -g >>> > flag? >>> >>> Yes, here it is with four points describing a 1 km side square : >>> >>> m.measure >>> coordinates=922000,2106000,923000,2106000,923000,2107000,922000,2107000 >>> units=meters >>> Length: 3000.00 meters >>> Area:100.00 square meters >>> >>> m.measure -g >>> coordinates=922000,2106000,923000,2106000,923000,2107000,922000,2107000 >>> units=meters >>> units=meters,square meters >>> length=3000.00 >>> area=100.00 >>> >> I actually didn't want you to use the units parameter, this is why you got >> reasonable outputs. Without it you would probably get segmentation fault. I >> created a ticket for this: >> http://trac.osgeo.org/grass/ticket/2157 >> >>> Having a closer look at my PROJ_UNITS file, I noticed unit was set to >>> "metre" and units was set to "metres". I tried to change these values to >>> "meter" and "meters". And now it works just fine. >> >> >> Yes, that makes sense. I was wondering why do you have metres instead of >> meters there? >> >>> >>> I can't say when and how one can tweak this variable. >>> Do you think this enhancement could be easily backported to 6.4 ? >> >> >> Unfortunately not. One thing is the GUI part which I would have to write >> again for grass 6 because although it looks the same, the code of wxGUI is >> quite different. And write it for grass 6 would be more difficult. The other >> thing is that m.measure is only a grass 7 module so I don't know which >> backend should be used for grass 6. >> >> Regards, >> Anna >> >>> >>> Yours, >>> V. >>> >>> >> > > > ___ > grass-dev mailing list > grass-dev@lists.osgeo.org > http://lists.osgeo.org/mailman/listinfo/grass-dev ___ grass-dev mailing list grass-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-dev
