I posted a few months ago about a new R package I wrote with Filipe Matias-- it's available for download on GitHub. Last week we extended the GitHub tutorial to include interpolation methods and raster visualization/mapping example code. Spatially Challenged readers have asked me to write tutorials on these techniques before, but I had been… Continue reading Inverse Distance Weighting and Kriging in R
Tag: free
EJSCREEN: a tool for visualizing Environmental Justice
This week I learned about a great tool from the US EPA called EJSCREEN, which allows users to visualize and download data related to environmental justice. The US has a long history of environmental racism, including building highways through predominantly black neighborhoods and using former factory sites for low-income housing. Pollution and increased noise exposure… Continue reading EJSCREEN: a tool for visualizing Environmental Justice
R Cheat Sheets: ggplot2- Updated Blog Post
Note: the below was originally written and published in November 2018. I edited the post for clarity and added a few notes on accessing some learning resources in R Studio itself, but you can still find the original here. This month I'm making lots of graphs in R and wanted to share some of the… Continue reading R Cheat Sheets: ggplot2- Updated Blog Post
Publicly Available Data Sets for Learning and Teaching
Whether you're learning basic coding in R or mastering the intricacies of mixed-model ANOVAs in SAS, it helps to have some data to practice with. I frequently make up small data sets for this blog based on random number sequences or subsets of other data I've collected, but when I need larger data sets these… Continue reading Publicly Available Data Sets for Learning and Teaching
R Tutorial by Hasse Walum and Desirée de Leon
I came across this truly delightful introduction to R and summary statistics tutorial while reminding myself how to write functions in R. I was impressed by how Teacups, Giraffes, & Statistics covers R basics with clarity and specificity while being incredibly endearing. This was the first place I've seen interactive R windows on websites, and… Continue reading R Tutorial by Hasse Walum and DesirĂ©e de Leon
Project CRS
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
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