centroid

问题 I'm having some trouble with the ST_CENTROID function in bigquery. There is a difference between getting the centroid of a GEOGRAPHY column and from the same WKT version of the column. The table is generated using a bq load with a geography column and a newline_delimited_json file containing the polygon as wkt text. Example: select st_centroid(polygon) loc, st_centroid(ST_GEOGFROMTEXT(st_astext(polygon))) loc2,polygon from table_with_polygon Result: POINT(-174.333247842246 -51.6549479435566)

问题 This Question is more Theoretical, and not specifically trying to problem-solve. I recently was introduced to the K-Means Clustering algorithm, and unsupervised machine learning algorithm, and I was intrigued by the though that one some sets of data, even if completely random, the average centroids drawn could keep changing through each iteration. Example: What I am trying to show here, is, imagine if the program flipped between iteration 6, to iteration 9, and kept doing this forever. I have

问题 I cant use the .centroid() method because its returns [NaN,Nan]. I dont know what is the right data format. var pathh = d3.geo.path(); d3.selectAll("path.line") .each(function (d, i) { var centroid = pathh.centroid(d); console.log('Centroid at: ', d,+ centroid[0] + ', ' + centroid[1]); }); My data format is: One object is one point(vertex) of the polygon 0: Object area_id: "IVP001" vertex_id: "37451" x: "100" y: "100" 1: Object area_id: "IVP001" vertex_id: "37452" x: "150" y: "120" 2: Object

问题 I cant use the .centroid() method because its returns [NaN,Nan]. I dont know what is the right data format. var pathh = d3.geo.path(); d3.selectAll("path.line") .each(function (d, i) { var centroid = pathh.centroid(d); console.log('Centroid at: ', d,+ centroid[0] + ', ' + centroid[1]); }); My data format is: One object is one point(vertex) of the polygon 0: Object area_id: "IVP001" vertex_id: "37451" x: "100" y: "100" 1: Object area_id: "IVP001" vertex_id: "37452" x: "150" y: "120" 2: Object

问题 I am SUPER new to python coding and would like some help. I was able to segment each cell outline within a biological tissue (super cool!) and now I am trying to find the centroid of each cell within a tissue using this: I am using this code: img = cv2.imread('/Users/kate/Desktop/SegmenterTest/SegmentedCells/Seg1.png') image = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY) thresh = cv2.threshold(image, 60, 255, cv2.THRESH_BINARY)[1] cnts = cv2.findContours(thresh.copy(), cv2.RETR_EXTERNAL, cv2.CHAIN

问题 I am trying to manipulate some Brazilian Census data in R using the new "sf" package. I am able to import the data, but I get an error when I try to create the centroids of the original polygons library(sf) #Donwload data filepath <- 'ftp://geoftp.ibge.gov.br/organizacao_do_territorio/malhas_territoriais/malhas_de_setores_censitarios__divisoes_intramunicipais/censo_2010/setores_censitarios_shp/ac/ac_setores_censitarios.zip' download.file(filepath,'ac_setores_censitarios.zip') unzip('ac

问题 Closed. This question is off-topic. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 2 years ago . I have a data set with (labeled) clusters. I'm trying to find the centroids of each cluster (a vector that his distance is the smallest from all data points of the cluster). I found many solutions to perform clustering and only then find the centroids, but I didn't find yet for existing ones. Python schikit

问题 I have a table in Oracle 18c that has an SDO_GEOMETRY column with polylines. I want to query the X and Y coordinates of the polyline midpoints using SQL. Is there a way to do this with Oracle Spatial? 回答1: Oracle Spatial has a linear referencing package called SDO_LRS. It can be used to find the midpoint coordinates of a polyline. --In this case, 'sdo' is the name of the sdo_geometry column. sdo_lrs.convert_to_std_geom(sdo_lrs.locate_pt(sdo_lrs.convert_to_lrs_geom(sdo,3) ,sdo_geom.sdo_length

问题 Summary: I thought that using gCentroid in R would return the centroid of a group of points, however I realised that for some reason it actually returns the geometric mean and not the centroid I wanted to replicate a centroid calculation I did in R: gCentroid {rgeos} The centre of mass of these points: 34.7573, -86.678606 38.30088, -76.520266 38.712147, -77.158616 39.704905, -84.126463 ... using the r-script ... require(rgdal) require(rgeos) no_am_eq_co <- "+proj=eqdc +lat_0=0 +lon_0=0 +lat_1

问题 I've been using an old revision of Three.js for quite some time, so I decided to upgrade to the latest (r68). I knew I would bump into some issues, but I wasn't expecting the removal of geometry.computeCentroids() and .centroid property. I'm loading models using the OBJMTLLoader library. The problem with this is that since it no longer has the .computeCentroids() method, I have no way of getting them. I've tried to calculate them using other methods, but to no avail: Three.js How to get