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16

Any time you have a selection on a layer a cursor object will only return the selected rows. for row in arcpy.SearchCursor("name_of_layer_with_selection"): print row.field1, row.field2


14

In the Table of Contents window, there is a button across top titled "List By Selection". Clicking this button toggles the Table of Contents into a mode that lets you change the selectablity of each layer in your dataframe.


9

Without knowing what your data looks like, the general syntax you need to insert into the select by attributes window is: [FIELD_1] IS NULL OR [FIELD_2] IS NULL OR [FIELD_3] IS NULL and so on for as many fields as you have to work with. For reference the full query would be: SELECT * FROM [TABLE_NAME] WHERE [FIELD_1] IS NULL OR [FIELD_2] IS NULL OR ...


9

You can use the Feature Class To Feature Class python snippet. Here is the general syntax. FeatureClassToFeatureClass_conversion (in_features, out_path, out_name, {where_clause}, {field_mapping}, {config_keyword}) To output to a shapefile, make sure that your out_path is a folder (and not pointing within a file geodatabase), and that out_name has a ...


9

Two possible solutions: You can use the "Vector->Research tools->Select by Location" and tick the "Use selected features only" checkbox. If you want to actually export the points which intersect your selected polygon to a new shapefile then "Vector->Geopressing tools->Intersect" and again tick the "Use only selected features" checkbox. The input layer will ...


8

You can unselect features with unselect and unselectAll methods of SelectFeature control: selectControl = new OpenLayers.Control.SelectFeature(vectorLayer); ... map.addControls([selectControl]); selectControl.activate(); // unselect any specific feature... selectControl.unselect(vectorLayer.features[0]); // ...or all features selectControl.unselectAll(); ...


7

Another approach to this would be to use the Spatial Join tool. Use the point as your input feature layer as above and the polygon layer as your identity features.Unlike SelectLayerByLocation, SpatialJoin does honor the extent environment. targetlayer = layername joinlayer=arcpy.PointGeometry(arcpy.Point(x, y)) fieldmappings = arcpy.FieldMappings() ...


7

There doesn't seem to be a way to directly find a feature object's parent layer or whether it's selected from a method in the QgsFeature class. A similar approach to vlayer.selectedFeatures() is to test whether the feat.id() is in vlayer.selectedFeaturesIds(). QgsFeatureIds are not unique values compared with other vector layers, only within their own ...


7

Instead of: "'ZIP' = '10004'" try this: '"ZIP" = ' + "'10004'" The reason that your original expression gives an empty output is because the string 'ZIP' is not the same as (equal to) the string '10004'.


7

create a new polygon layer, draw a single polygon that covers all your current polygons, then cut the newly drawn polygon based on all your existing polygons, then select all polygons from you current set that share a line segment with the newly drawn polygon using select by location and you're done ---Edited version much more efficient, based on ...


7

In arcpy, When you implement the Search Cursor or Update Cursor you have the option of using the where_clause parameter, which will allow you to select a specific row based on a field value (e.g. row ID). This help file will show you how to build an appropriate SQL query for selecting a specific row.


6

Use the looping and variable value as shown in Aragon's answer with the FID field (this is the zero-based object ID field for shapefiles) as the select field as shown in L_Holcombe's answer to generate the where clause, and all should be good. To program in the total number of features use the Get Count tool and divide by 10 assigned to the variable. Will ...


6

Edit: The first method I posted wouldn't work. This one should though. One straightforward way to do this would be to select everything you want to keep via Make Feature Layer with a where clause of X <> c. Then, use Copy Features to save the result.


5

Toolbars are located outside your screen area. You can use Python console to move them on screen. Here is example of moving Navigation Toolbar: qgis.utils.iface.mapNavToolToolBar().move(10,10) Names of other toolbars can be found by this link.


5

The select tool has a "Select by Rectangle" option. (There are also freehand/polygon options if that would be more appropriate.) The node tool is for digitizing. I don't think that's what you want to do here. Then, right-click on the layer in layer list and use "Save selection as ...". This will create a new file with the features you selected. (You can ...


5

This example should show you exactly what you need. http://openlayers.org/dev/examples/select-feature-multilayer.html


5

I ended up making the function suggested below. In part inspired by inputs from other contributors on this question. The object handling is coarse and it creates a lot of temporary files. I am sure this function could be made a lot better. If properly polished it could be a decent preliminary fix for the dissolve bug by ESRI. I am making it a community ...


5

You could try the Identity tool, using your line features as the input, and polygons as the identity features: "When the Input Features are lines and the Identity Features are polygons, and the Keep relationships parameter is checked (relationship set to KEEP_RELATIONSHIPS), the output line feature class will have two additional fields, LEFT_poly and ...


4

I am thinking you could do a spatial join of the points to your buffered polys which will join the attributes of both together, then you can select back the points that have matching ColumnX and ColumnY values.You can do just a Intersect or Identify as well, all three will give you a very similar result to append the attributed from the poly to the point ...


4

You will need to use the Make Feature Layer tool on your feature class first, then you will be able to use Select Layer By Attribute on that.


4

You can use enumarete function in python. myList = [] n = 99 for i, v in enumarete(myList): if i == n: print v 'first 100 item' #append your list if i > n and i < (n+2)*2: print v Or you can use this script from SO: def split_list(alist, wanted_parts=1): length = len(alist) return [ alist[i*length // wanted_parts: ...


4

Sorry, your introduction is very unclearto me. You are obviously searching for some "smart" solution, only those python geeks and R-specialists can give you ... Here my "unsmart" approach: Assuming you have fields for the species and date. create a new text field with field calculator, concatenate there the species name and the date, so you will have a ...


4

Unlike Arc you need to have the layer you want to identify highlighted in the table of contents as well as turned on. I think the deselect feature isn't doing anything if you don't currently have any layers selected. Also see this answer: QGIS identify features button issue


4

Use the Summary Statistics tool with the following parameters: Input Table: your point feature class Statistics Field: the address value field. Select MIN as the statistic type from the dropdown list. Case Field: the parcel address field. This will group records according to the Case Field, select the minimum address value and write this value to the new ...


4

After a feature is selected, it's added to the vector layer's selectedFeatures array (and removed after it's deselected) You can test it in your browser: http://openlayers.org/dev/examples/select-feature.html Draw a polygon Open JS console (i.e. Firebug or Chrome dev tools) Type: var vectorLayer = map.getLayersByName("Vector Layer")[0]; var feature = ...


3

you should gieve a try to "mask" plugin: http://plugins.qgis.org/plugins/mask/ You can either select by hand or query your objects. It takes them, dissolve them and create a hole in a square feature that is 4 times larger than select objects. It adds a semi-transparent memory layer to your project. If Memory layer saver plugin is installed, your project ...


3

You could modify selectBox method of SelectFeature control: OpenLayers.Control.SelectFeature.prototype.selectBox = function(position) { if (position instanceof OpenLayers.Bounds) { var minXY = this.map.getLonLatFromPixel( new OpenLayers.Pixel(position.left, position.bottom) ); var maxXY = this.map.getLonLatFromPixel( new ...


3

Select the features, right click on the layer, "Save selection as"-> *.kml


3

Perhaps something simple would work? Assuming "gid" is a column with consecutive integers: arcpy.Select_analysis("in_features", "out_features", '"gid" < 400') arcpy.Select_analysis("in_features", "out_features", '"gid" < 800 AND "gid" >= 400') etc. I haven't tried this, but it should work. ArcGIS SQL expression reference: ...


3

The problem with your code lies in the logical flow and that you are selecting all the parcel features each time your arcpy.SelectLayerByLocation_management is called. You should re-work your code flow to: First cursor/select each neighborhood feature (within cursor use select by attribute) Select by location using neighbohood selected features to select ...



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