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21

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


16

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.


12

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 ...


11

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

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 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(); ...


8

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() ...


8

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 ...


8

Kadeem's modified answer will prevent your features from being visible, but they will still be present, if you are trying to identify an individual ship track you may click an invisible feature by mistake. What it seems like you need to do is define your layer so that it's as if those features don't exist. In ArcGIS this would usually be done using a ...


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

Right click on layer name: Selection -> Make This The Only Selectable Layer Fine control of selectable layers: In table of Contents switch to List by Selection view and then choose which layer are selectable:


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 ...


5

Kristina, I assume there is an attribute in your table which allows you to identify a single track? For example: point_id | track_id ------------+------------ 1 | 15 2 | 15 5 | 24 6 | 24 7 | 24 If you open the attribute table, you can find an epsilon symbol (in the figure below, the ...


5

I don't think you can remove features from a selection layer once it's been created, but the workaround that I usually use is to create a new selection layer from your existing one: Select the features in your selection layer that you want to remove. Open the selection layer's attribute table and click Switch Selection, which will make all the features ...


5

You need a ST_GeomFromGeoJSON select * from points p where ST_Within( p.geom, ST_GeomFromGeoJSON('{"type":"Polygon","coordinates":[...]}') ) Edit: ST_Intersects works also (need to set SRID on GeoJSON, and transform): select row_to_json(t) from (select * from table where st_intersects( st_transform( st_setsrid( ...


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

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


4

You can use the IFeatureSelection::SelectionSet property to return an ISelectionSet. This has the RemoveList method, where you can supply a list of OIDs to be removed from the selection set.


4

Sounds like you want to select features and not clear the selection graphics layer each time you click a feature. If you're using a FeatureLayer, you would use SELECTION_ADD instead of SELECTION_NEW to add the selected features as you click on them.


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

the Describe function will also return a list. I am not sure if this is faster than the cursor method but I have fond this to be a useful tool. The resulting list is the object id's for the selection set. import arcpy aa = arcpy.Describe("someFC") ss = aa.FIDset tt = ss.split("; ") Print tt [u'1363', u'1364', u'1365', u'1367', u'1369', u'1370']



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