python - Pysal doesn't recognize some polygon neighbors -


i'm using pysal tool analyzing several shapefiles (type polygon) contain results of segmentations done in qgis.

i load shapefile using

segshp = pysal.weights.queen.from_shapefile(vect)

being vect name of corresponding shapefile.

the problem when in neighbors dictionary, if polygon shares less 2 pixels not considered neighbor. let me show bit better:

using arcgis, calculate polygon neighbors (analysis tools --> proximity ---> polygon neighbors), , example, polygon 1227 has 4 neighbors shown in image.

neighbors calculated arcgis

but when loading in python using pysal, polygon 1227 has 3 neighbors , 1 missing 3307, shares 2 pixel border. same happens other polygons share 1 or 2 pixels. "threshold" of 2 pixels have seen analyzing polygons.

neighbors calculated pysal

is there anyway of changing "threshold" in order consider neighbors? i've seen in pysal documentation , thought maybe it's related command

pysal.weights.user.min_threshold_dist_from_shapefile

or similar, got no idea.

i tried pysal.weights.rook... option, recognizes less neighbors , finds more islands.

thanks lot

thanks @charles.

indeed seems problem. checking vertices, although polygon 1227 , 3307 share common border, don't share vertices. once edited them manually , corrected small difference in coordenates of new vertices, pysal tool recognize them neighbors. checking geometry of shapefile not generates invalid geometries, neither in arcgis or qgis.

i'll try figure way create "missing" vertices in these cases, can "fix" geometry before pysal line (any ideas matter welcome).

anyway, , respecting original question issue has been solved.


Comments

Post a Comment

Popular posts from this blog

Is there a better way to structure post methods in Class Based Views -

i'm using class based views in django , never specify url in ajax calls , omit action parameter in form because know these requests go through post method of class based view. notice view - profile page make many requests depending on user updating on page - post method become convoluted , if/else mess example: def post(self, request, *args, **kwargs): # handle user changing available date if request.post.get('availabledate') != none: self.updateavailabledate(request) return jsonresponse({'result':'success'}) if request.post.get('newprojectname') != none: creative_user = creativeuserprofile.objects.get(id = request.user.id) project = project.create_project(creative_user, request.post['newprojectname']) project.save() return jsonresponse({'projectid': project.id }) if request.post.get('projectimage') != none , request.files['file']: proj...
Read more

performance - Why is XCHG reg, reg a 3 micro-op instruction on modern Intel architectures? -

i'm doing micro-optimization on performance critical part of code , came across sequence of instructions (in at&t syntax): add %rax, %rbx mov %rdx, %rax mov %rbx, %rdx i thought had use case xchg allow me shave instruction , write: add %rbx, %rax xchg %rax, %rdx however, dimay found agner fog's instruction tables , xchg 3 micro-op instruction 2 cycle latency on sandy bridge, ivy bridge, broadwell, haswell , skylake. 3 whole micro-ops , 2 cycles of latency! 3 micro-ops throws off 4-1-1-1 cadence , 2 cycle latency makes worse original in best case since last 2 instructions in original might execute in parallel. now... cpu might breaking instruction micro-ops equivalent to: mov %rax, %tmp mov %rdx, %rax mov %tmp, %rdx where tmp anonymous internal register , suppose last 2 micro-ops run in parallel latency 2 cycles. given register renaming occurs on these micro-architectures, though, doesn't make sense me done way. why wouldn't register renamer ...
Read more

c# - Asp.net web api : redirect unauthorized requst to forbidden page -

im trying redirect unauthorized request forbidden page instead i'm getting forbidden page in response body , how can fix ? here's startup class : app.createperowincontext(storecontext.create); app.createperowincontext<applicationusermanager>(applicationusermanager.create); app.createperowincontext<applicationsigninmanager>(applicationsigninmanager.create); app.usecookieauthentication(new cookieauthenticationoptions { authenticationtype = defaultauthenticationtypes.applicationcookie, expiretimespan = timespan.fromdays(30), }); app.useexternalsignincookie(defaultauthenticationtypes.externalcookie); app.usetwofactorsignincookie(defaultauthenticationtypes.twofactorcookie, timespan.fromminutes(5)); app.usetwofactorrememberbrowsercookie(defaultauthenticationtypes.twofactorrememberbrowsercookie); the method im trying reach : [httpget] [authorize(roles = "admin")] public string getcurrentusername() { return userman...
Read more