Using R in QGis processing

Although R is essentially a set of statisticals, its use has been extended to a number of areas, such as natural language processing. This library possesses also solic tools of spatial analysis, including analysis of the distributions of points and the Bayesian geostatical modelling. It is possible to read and manage a variety of vector and raster data, including shapefiles, NetCDF and GDAL.

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Points to Line with QGis

In a previous article we discussed how to create a layer lines from a file text or Excel with Arcmap . Now is the turn with QGis.There are only two differences :

  • the first is that it is not necessary to load the Excel table, and then save it in as a layer (shapefile)
  • the second is that there is no option to close automatically the lines by linking the last point to the first point of each line .
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New ArcMap tools : Points to line

Since delivery of the 10.3 version, there are some new ArcMap tools available that deserve to be better known . Here is a series of articles regarding their description. Firstly, we will discuss the “Points to line” tool,  You, probably,  know the procedure for integrating a table of points, in text format or Excel, as a layer of points in Arcmap . If this is not the case , it will be described a little further in this article. What is less known is that you can as well incorporate tables containing rows as series of points, such as GPS routes. Let’s see for example a bathymetry layer.   

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The Autofields plugin for QGis

The Autofields plugin for QGis allows filling automatically the attribute fields of a layer when creating or publishing entities. You can, for example, fill a field with the value of x or y of the point, or the beginning point of a segment, the segment length, etc. You can use this plugin from version 2.12 of QGis and only from version 2.14 if you use the calculations based on the geometry requiring coordinate system transformations.

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How to make an svg symbol editable ( color , stroke ) in QGis

If you import or create svg symbols to use  them in QGis you will notice that the color options as well as the outline of these symbols are disabled in QGis. In fact , these settings are coded in hard in the svg file and , if you want to make them available , you are forced to create as many symbols as colors desired .

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How to update a Postgresql / PostGIS database with LibreOffice

Even  if it can look weird (use a GIS tool not to update a GIS base) there are occasions when it proves very useful.

A GIS base comprises two types of information : spatial information ( geometry ) and attributes information . For many field projects there is untrained GIS staff responsible for maintaining the information , especially attributes , of a GIS database.

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