Thanks Robert. I did something like that with Spatialite for a consulting project last summer.
I think that I have some reasonable solutions now, I am just trying to compare the speeds and tune them. I can fairly easily make ugly, brute force use of the modules, I hoping to take advantage of the features of the modules. It is in trying to figure out those idioms or best practices that I am struggling. I am actually replacing a few processes where I load data into PostGIS, do the queries and write the data back out to a different database, all using Python as the glue. My goal is to do it all in Python, unencumbered by proprietary licenses. David. On Tue, Mar 26, 2013 at 2:59 PM, Robert Sanson < [email protected]> wrote: > One other options might be to load data into Spatialite, and then use > Python to loop through and execute the queries. I don't know whether > this would be faster or slower, but the spatial queries should be able > to handle the different types of geometries. > > regards, > > Robert > > >>> David Fawcett <[email protected]> 27/03/2013 2:30 a.m. >>> > Thank you Esteban. > > Using a list or a list of dicts for the points makes sense. I am > thinking > that I would then need to create each point geometry on the fly as I > loop. > I will test this out. > > In this case, one of the feature collections has a geometry type of > pont, > but in other cases that I have, it is line or polygon. I am hoping to > figure out a solution that can efficiently work for all of these > cases. > > My goal is really to leverage Shapely and get the most simplicity and > efficiency that I can. If I can use existing shapely/fiona data > structures, I would like to. > > I haven't been able to find any examples that fit this case very well. > I > can promise a pull request with an example. > > Thanks, > > David. > > On Mon, Mar 25, 2013 at 5:14 PM, Esteban Munoz <[email protected]> > wrote: > > > Hi David, > > > > try creating a list first: > > > > for country in list(countryCollect): > > > > then when you have found the station you may want to delete that > station > > from the loaded data. Normally you would do that with the remove > command: > > stationCollect.remove(station)**. Unfortunatlly that works only with > list > > data formats... > > > > Cheers, > > Esteban > > > > David Fawcett writes: > > > > * HTML content follows * > >> > >> I am working through a couple of iterations of examples using > Shapely do > >> point in poly intersects. I plan to add prepared geometries and > rtree in > >> future examples, but I am starting with the basics. > >> I have county polys and station points. I am using fiona to open up > the > >> shapefiles and create collections. > >> My outer loop goes through the counties and the inner loop goes > through > >> each station, testing whether the station intersects() the county. > >> It appears as though I need to reset or recreate the station > collection > >> between each outer loop iteration. It seems inefficient to reload > the > >> collection from disk each time, but I don't see a .reset() method > or > >> anything like that. > >> What is the best way to implement this? In the below example, I > only get > >> a list of station xy's in the first iteration of the outer loop. > >> > >> Thanks, > >> David. > >> > >> stationCollect = fiona.open(stationPath,'r') > >> countyCollect = fiona.open(countyPath,'r') > >> > >> for county in countyCollect: > >> countyGeom = shape(county['geometry']) > >> > >> for station in stationCollect: > >> stationGeom = shape(station['geometry']) > >> print stationGeom.x, stationGeom.y > >> if stationGeom.intersects(**countyGeom): > >> print station['properties']['SYS_**LOC_CO'] > >> print county['properties']['**COUNTYNAME'] > >> > >> countyCollect.close() > >> stationCollect.close() > >> > >> -- > >> You received this message because you are subscribed to the Google > Groups > >> "Unofficial Python GIS SIG" group. > >> To unsubscribe from this group and stop receiving emails from it, > send an > >> email to > python-gis-sig+unsubscribe@**googlegroups.com< > python-gis-sig%[email protected]> > >> . > >> For more options, visit > <URL:https://groups.google.**com/groups/opt_out< > https://groups.google.com/groups/opt_out> > >> >https://**groups.google.com/gro > <https://groups.google.com/gro>ups/opt_out. > >> > >> > >> > > > > -- > > You received this message because you are subscribed to the Google > Groups > > "Unofficial Python GIS SIG" group. > > To unsubscribe from this group and stop receiving emails from it, > send an > > email to > python-gis-sig+unsubscribe@**googlegroups.com< > python-gis-sig%[email protected]> > > . > > For more options, visit > https://groups.google.com/**groups/opt_out< > https://groups.google.com/groups/opt_out> > > . > > > > > > > > -- > You received this message because you are subscribed to the Google > Groups "Unofficial Python GIS SIG" group. > To unsubscribe from this group and stop receiving emails from it, send > an email to [email protected]. > For more options, visit https://groups.google.com/groups/opt_out. > > > > > This email and any attachments are confidential and intended solely for > the addressee(s). 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