Filter Data into separate layers in Leaflet

Filter Data into separate layers in Leaflet

GIS, Leaflet, Programming, Tutorials
Data loaded in Leaflet as a layer can be filtered on the fly to create separate layers that meet a certain criteria. This is very helpful when handling data that is not too huge for the browser. I have a done a video tutorial to demonstrate how to filter data on-the-fly in Leaflet. This tutorial uses GeoJSON data. Subscribe to the YouTube Channel for more videos and tutorials
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3D Maps with Leaflet and eegeo.js

3D Maps with Leaflet and eegeo.js

General, Leaflet, Programming, Slider, Tutorials, Web-GIS
We like maps and will continue like them more. Every day, there are changes in the libraries used for mapping. With most maps being 2D, exploring 3D maps is so much fun and better.\ In this post, I describe a procedure to display 3D maps for your web mapping project. First, we will have a HTML file that will handle our map page. Steps: Write a basic HTML file with a title of your wish. <!DOCTYPE html> <html> <head> <title>3D Map</title> </head> <body> </body> </html> Add the Leaflet CSS inside the <head></head> section <link rel="stylesheet" type="text/css" href="https://unpkg.com/leaflet@1.0.3/dist/leaflet.css"> You can also load this from your local computer Add the eegeo JS library inside the <head></head> section <script type="text/javascript" src="https://cdn-webgl.eegeo.com/eegeojs/api/v0.1.780/eegeo.js"></script> Add the section in which the map will be displayed <div id="map"…
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Nearest neighbor Analysis in QGIS

Nearest neighbor Analysis in QGIS

GIS, QGIS, Software, Tutorials
GIS is very useful in analyzing spatial relationship between features.It is important at times to find the features nearest to a feature in GIS.To achieve this, we can use the Distance Matrix that helps in calculating the distances between each point in the dataset. Steps You can use Vector > Analysis Tools > Distance Matrix, and a join to have an output layer that has all the required attributes. I will use the Towns layer to exemplify. This will help in showing the distances and is quite small for faster processing. 1. Create a distance matrix using your layer as both destination and target. Don't forget to tick "Use only the nearest (k) target points" and set it to 1. Distance Matrix Window 2. Open the CSV with add delimited…
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3D visualization of Data in QGIS

3D visualization of Data in QGIS

Highlight, Tutorials
Well, this is a topic that I have always wanted to write about but have been a little bit reluctant.I think this has been attributed to the fact that I didn't find people who wanted to use this feature.Last week, I found someone who really wanted this in their project.Here is the thing, if you want to have a 3D view of your data, QGIS provides an out-of-the-box plugin (Qgis2threejs) that really helps us in doing this.Take a look. Steps Load you data in QGIS canvas.In my case am using data for Nairobi buildings with a height attribute. We will be creating a 3D view of our buildings as an overlay on OpenStreetMap baselayer. Launch the Qgis2threejs plugin from the Web Menu.(Web > Qgis2threejs > Qgis2threejs) if you have Qgis2threejs…
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Using QGIS Layer Styles in GeoServer

Using QGIS Layer Styles in GeoServer

GIS, QGIS, Software, Tutorials
GeoServer provides us with the functionality of styling our layers to match our preferences. However, many are the times that many GeoServer users face problems while publishing their layers. Styling in GeoServer should be an easy task when doing web applications or publishing your GIS layers via GeoServer. [caption id="attachment_181" align="aligncenter" width="390"] Expected Results[/caption] Today, I will focus on how to apply same styles for layers in GeoServer as in your QGIS project. Here are a few steps that can be followed to achieve the expected results. Load a PostGIS layer in the map canvas in QGIS using the Add PostGIS layers option in Manage Layers toolbar.   The Add PostGIS tabledialog box appears and it gives the option to add a connection to our PostGIS tables Add connection Fill…
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Generating Contours from  DEM in QGIS

Generating Contours from DEM in QGIS

GIS, QGIS, Software, Tutorials
      A few weeks ago I wrote a post on “Generating DEMs from Contours” which was quite a straight forward process as explained.In this post , I will show how to “reverse engineer” the process and generate contours from DEMs. This time round am also going to demonstrate how to clip our dataset to work with the area of interest instead of working on the whole dataset. Lets begin: Assumption: You have the DEM on your local machine. If not so, data can be downloaded from either USGS EarthExplorer or from GeoComm Steps: Launch QGIS 2.X and Load our Raster Layer (DEM) i.e. Ken_dem (sample data for this tutorial) [caption id="attachment_187" align="aligncenter" width="640"] Load DEM in QGIS[/caption]   Go to Raster > Extraction > Clipper (This will help us in…
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Generating DEMS from Contours in QGIS

Generating DEMS from Contours in QGIS

GIS, Tutorials
Well, Today was a great day in my GIS works. A colleague asked “Can I generate a DEM of my region using QGIS?” This was my answer to them “YES”. Then they asked me “How?” I ended up spending the next one hour doing the demo on my laptop for them to grasp the rough idea on how to go about this issue. That question motivated me to write this post so as to help other persons/groups out there who might be stuck in this issue like my good friend. Here are the steps for generating a DEM (Digital Elevation Model) from CONTOURS using GRASS Plugin in QGIS. To start, ensure you have the GRASS plugin installed in your QGIS (Plugins > Manage and Install plugins >GRASS) Load the “Contours” …
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Publishing maps using QGIS Cloud

Publishing maps using QGIS Cloud

GIS, QGIS, QGIS Cloud, Software, Tutorials, Web-GIS
Sharing the outputs of your GIS work with other people on the globe has become a common practice nowadays. The methods used in sharing this information matters and depends on a number of things;the availability of storage space to store your datasets, the cost of operating a web map,user interactivity of your web maps,the kind of technology the web map uses and many more. QGIS have the QGISCloud that is can be used to publish maps online within FIVE minutes.Another advantage is that QGIS is Open Source thus no worry of startup costs.This tutorial will demostrate how to publish a map using QGISCloud. Steps To publish a map using QGISCloud, you need to first install the QGISCloud Plugin.This can be done at “Manage and Install plugins” under the Plugins Menu…
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