QGIS: Difference between revisions
No edit summary |
No edit summary |
||
Line 1: | Line 1: | ||
[[Main_Page|Main Page]] | |||
__FORCETOC__ | __FORCETOC__ | ||
===QGIS - Mapping and other Functions=== | ===QGIS - Mapping and other Functions=== |
Revision as of 21:11, 17 June 2020
QGIS - Mapping and other Functions
In addition to the built-in ArcGIS functionality some may wish to use the free (open source) program QGIS. QGIS is a professional GIS application that is built on top of and proud to be itself Free and Open Source Software (FOSS). QGIS runs on Windows, Mac and Linux and is an excellent way to view your data on your computer. This program has a lot of functionality but the learning curve can be rather steep. It can be downloaded from the QGIS Website For those who choose to use it here are some tips for accessing some of the basic functions such as loading data into maps. In addition to many other functions these are the most common functions Golden Retriever users you will most likely use:
These tips work on most versions of QGIS available as of March 2020. However, future versions of QGIS may include functionality or menu location changes. If you notice anything missing for changed please let us know at info@goldenretrieverapp.com with QGIS in the subject line. - Thanks!
Open shapefile or add layer from csv
Each map is made up of different layers. For example you may have one layer with pole locations, one with meter locations and one with a street map. Map layers can be either loaded from the .shp
file in your shapefile folder or by adding a layer to your map from a .csv
(delimited) file.
Opening a Shapefile
Either load the .shp
from your computer's file browser or open the QGIS Desktop application and open a shapefile using the Browser Panel. This will give you a map showing your data point locatioins.
Creating Layer from CSV
You may also view a map of your data from a .csv
file. Since there are many different GPS coordinate systems in use you will need to know what coordinate system yours is in. If you downloaded your data directly from Golden Retriever Admin Portal the GPS coordinates will be in a EPSG:4326, WGS 84 format.
Install Quickmap plug-in
Under the Plugins menu item select Manage ind Install Plugins.... Once the available plugins windows has loaded search for the QuickMapServices and install it. Once installed it can be found under the Web main menu.
Add Quickmap layer
Under the Web main menu item select Quick Map Services → OSM → OSM Standard to load the Open Street Map standard map. There are quite a few other options available but often require further setup and a license fee. The OSM Standard is very good and allows you to view your data points on a detailed street map (and some cases even transmission lines are shown). Now that you have your data points and a street map you can view their locations and zoom in/out as needed.
Add Pole Number to data layer
When you opened your inspection data file into QGIS all of the associated data was also loaded by default. You can view things like the Pole Number quite easily. Other viewing options are also available but are beyond the scope of this wiki. To add a single data point attribute to your map view right-click the layer name and select Properties.
- Under the Labels heading change the Labels option from No Labels to Show labels for this layer
- Select the attribute you wish to view on the map from the list of available options (the database field names) i.e. Pole Number
Once you click Apply or OK you will see the chosen attribute on your map layer. Other viewing options here are font size, style, color among others.
Export/Save as image
Another option is to save/export the current map view as an image (bmp, jpg, png, etc). This is done, depending on the version of QGIS you are using, as a Save As Image or Export option in the Project menu item.
Exporting a csv for Golden Retriever from utility supplied shapefile
Sometimes you, as a contractor, will receive a shapefile from your utility customer containing the poles they want you to inspect. This is a compressed (or zipped) file when uncompressed (or extracted) is merely a folder with some files in it. According to Wikipedia, "the shapefile format is a digital vector storage format for storing geometric location and associated attribute information." The pole data will be stored in the .shp
file and the specific GPS coordinate system used will be found in the .prj
file. The .prj
is a text file and can be opened in a text editor such as Notepad. When Golden Retriever makes a shapefile all of the data is included in a .csv
file inside the shapefile folder for added convenience.
This initial pole data, including GPS coordinates, can be uploaded into your collection dictionary to aid in pole location and identification - it also saves time when entering pole data. To obtain this data follow these steps.
- Select Save As from the Layer main menu item.
- In the save window which will open up you will need to specify a name and location for the saved
.csv
- You may need to specify the CRS (GPS coordinate system) to EPSG:4326, WGS 84 which Golden Retriever uses.
- Set the Geometry to AS_XY
These should be the only variables you need to worry about. From here this file can be uploaded into a collection dictionary in the Dictionary Creator for use in the mobile app.
If you have any issues with this please contact your Golden Retriever representative or email the development team at info@goldenretrieverapp.com for any help you may require. We're happy to help.
These tips work on most versions of QGIS available as of March 2020. However, future versions of QGIS may include functionality or menu location changes. If you find QGIS helpful consider donating to its ongoing development.