on January 25, 2023
Difference between two layers in PostGIS
Geographic Information SystemsWhat is polygon in PostGIS? A polygon is a representation of an area. The outer boundary of the polygon is represented by a ring. This ring is a linestring that is both closed and simple as defined above. Holes within the polygon are also represented by rings. How do I create a polygon in PostGIS?
on January 25, 2023
Can primary keys and foreign keys be used in versioned geodatabases?
Geographic Information SystemsWhen should you not use foreign keys? Reasons not to use Foreign Keys: you are making the DB work extra on every CRUD operation because it has to check FK consistency. by enforcing relationships, FKs specify an order in which you have to add/delete things, which can lead to refusal by the DB to do
on January 25, 2023
What is the format of donuts in a polygon shapefile
Geographic Information SystemsHow do you make a donut polygon? You can cut holes in existing polygon features to create a donut polygon. Ensure point snapping is enabled. Click the Snapping menu on the Snapping toolbar and click Snap To Sketch. Click the Cut Polygons tool. Sketch the area you want to remove. To use an existing polygon
on January 25, 2023
Extract height from DTM into attribute table of point layer
Geographic Information SystemsHow do I extract elevation from DEM in ArcGIS? Note: Start ArcGIS Pro. Open a project with elevation data, or load a DEM in the table of contents. Choose the template for the elevation points. On the Edit tab, in the Features group, click Create Features . Click the elevation point layer on which you
on January 25, 2023
ArcMap closing when running ArcPy script?
Geographic Information SystemsWhy does my ArcGIS keep crashing? The most likely cause is the current default printer. ArcMap checks the margin, page size, and resolution of the default printer when starting up. If the driver or printer returns bad information, this can cause ArcMap to crash. How do I stop ArcGIS from crashing? To prevent crashes, ensure
on January 25, 2023
Checking layout for compatibility with b/w printing in ArcGIS Pro
Geographic Information SystemsHow do I print a layout in ArcGIS Pro? Print a map or layout by doing the following: Make sure a map or layout is your active view. On the Share tab, in the Print group, click Print Map or Print Layout. Choose a printer from the Printer Name drop-down list. Set any additional properties
on January 25, 2023
Can two people work on the same QGIS project in real time?
Geographic Information SystemsCan you share a Qgis project? A possibility is to save the project and all files (layers) to the same Geopackage file and send this. As this sometimes can be a bit tricky, an even easier way is to create a zip folder containing project and data. Where are project properties in Qgis? Project Properties
on January 25, 2023
One shapefile for African continent containing counties/regions?
Geographic Information SystemsWhat is a shapefile example? The shapefile format can spatially describe vector features: points, lines, and polygons, representing, for example, water wells, rivers, and lakes. Each item usually has attributes that describe it, such as name or temperature. Where can I find shapefiles? The U. S. Census Bureau is a great resource for shapefiles: geographical
on January 25, 2023
Renaming FCs in a Geodatabase with Python
Geographic Information SystemsHow do I rename a file in geodatabase? Rename a file geodatabase Click Databases in the Catalog pane, right-click the file geodatabase, and click Rename. Type a new name and press Enter. How do I change the name of a geodatabase in Arcgis? Follow these steps to rename a file or personal geodatabase: Start ArcMap
on January 25, 2023
Viewshed analysis using polygons in ArcGIS Desktop?
Geographic Information SystemsWhat parameters can we choose for viewshed analysis? A number of parameters can influence the result of a viewshed analysis including the viewpoint, the height of the observer, the viewing azimuth, the viewing radius, vertical viewing angle limits, the Earth’s curvature, and tree height. What is viewshed analysis in ArcGIS? A viewshed identifies the cells