Sometimes when you're generating new layers in QGIS, you don't get the results you're expecting. This could be due to your Project CRS being in weird units or not matching the other files you're working with. I broke out the same example file as the last few posts to show you how to change your… Continue reading Project CRS
Tag: free
Save a File with a New CRS
Last week I posted about on-the-fly projections, which is enabled by default in QGIS. It works so well that sometimes we forget when layers are in different coordinate reference systems until we try to run a geoprocessing algorithm. Fortunately, when you inevitably run into this issue it is very easy to solve. To illustrate this… Continue reading Save a File with a New CRS
Export Resolution in Draw.io
Last winter I briefly highlighted Draw.io, a free flow charting tool comparable to Microsoft Visio (see that intro here). I use Draw.io pretty frequently, but I still haven't written more detailed how-tos for Spatially Challenged. The interface is pretty user-friendly, so I didn't think there was much worth a step-by-step article. Today is the first… Continue reading Export Resolution in Draw.io
Stanford Open Courses
I am sharing this resource now because I just remembered how great it was while taking about SQL with a friend, and now I honestly feel bad that I haven't shared it with readers before now. If you aren't familiar with open courses, they are free, online ways to learn new skills. They vary in… Continue reading Stanford Open Courses
Geographically Weighted Regression in SAGA
Since I mentioned kernels last week, I figured this would be a good time to go over the geographically weighted regression (GWR) procedure in SAGA. Once again, I don't have good example data I can post online for this topic, so you'll have to forgive the lack of pictures. GWR is an interesting method with… Continue reading Geographically Weighted Regression in SAGA
Making Box Plots
Last month I posted about how to read box plots, and today I'm sharing how you can make your own. I picked two online tools that don't require you to calculate the mean and quartiles yourself and shared a quick couple lines of code for the R users out there. Let's start with Desmos! Desmos… Continue reading Making Box Plots
Data Downloads: Soil Maps
Today I'm continuing a series on sources of spatial data (see past posts on aerial images and DEMs). Soil maps are useful for all sorts of applications, like deciding where to place a trial in a larger field so that all the treatments are on the same soil type or determining the drainage class of… Continue reading Data Downloads: Soil Maps
Inverse Distance Weighting in SAGA
I broke out SAGA again this week to do some soil interpolations. I don't usually use inverse distance weighting (IDW) for much because you can't generate error maps or use covariates with this method. For this project I needed to make some maps in IDW to compare back to other methods. I'm using IDW for… Continue reading Inverse Distance Weighting in SAGA
Saving Layer Style Files in QGIS
Sometimes getting a layer to be displayed precisely how you want it can be a tedious process in QGIS. Fortunately, there is a way to save that style so you can apply it to the same layer in another project, or to another layer with similar attributes. Most of the time I use layer style… Continue reading Saving Layer Style Files in QGIS
Types of Curvature
Curvature, the second derivative of elevation, is a very useful terrain derivative. It describes how convex or concave a surface is, which helps predict soil moisture (among other things). The basic terrain analysis feature in SAGA calculates plan curvature and profile curvature. Profile curvature goes with the direction of maximum slope, which helps estimate acceleration… Continue reading Types of Curvature