This is only about 3 years late – but I gave a talk at FOSS4G 2021 on geospatial PDFs. The full title was: From static PDFs to interactive, geospatial PDFs, or, ‘I never knew PDFs could do that!’ The video is below: In the talk I cover what a geospatial PDF is, how to export […]
Here’s a bit of SQL I wrote recently that had an error in it which I struggled to find. The error I got was ERROR: invalid reference to FROM-clause entry for table "roads" and I did some Googling but nothing really seemed to make sense as a cause of this error. My SQL looked like […]
Summary: It might be because there is an exception raised when importing your function_app.py – for example, caused by one of your import statements raising an exception, or a parsing error caused by a syntax error. I was deploying a FastAPI app to Azure Functions recently. Azure Functions is the equivalent of AWS Lambda – […]
Summary: If appending to a PostGIS table with GDAL/OGR is taking a long time, try setting the PG_USE_COPY config option to YES (eg. adding –config PG_USE_COPY YES to your command line). This should speed it up, but beware that if there are concurrent writes to your table at the same time as OGR is accessing […]
I use GeoPandas for a lot of my vector GIS data manipulation in Python. I had a situation the other day where I ended up with duplicates of some geometries in my GeoDataFrame, and I wanted to remove them. The simple way to do this is to use the underlying pandas method drop_duplicates on the […]
Note: This blog post has been updated with a new command for creating an osx-64 environment, after I was contacted by someone from Anaconda telling me a newer, easier way to do this I came across some conda packages that didn’t work properly on my M1 Mac (Apple Silicon – ARM processor) the other day. […]
Just a quick one today to document the solution to a problem I ran into earlier today. I was using Microsoft Planetary Computer to access some Landsat satellite data, and I wanted to run it through the Segment Anything model from Meta, to segment out agricultural fields from the image. I tried to do this […]
I’m giving two talks in the next two weeks, and wanted to publicise them here in case anyone local-ish wants to come. Oxford Cafe Scientifique I’ve spoken at various Cafe Scientifique meet-ups before, and now it’s the turn of the Oxford one. I’ll be giving my talk about the whole range of satellite imaging – […]
In the spirit of my Previously Unpublicised Code series, today I’m going to share Pandas-FSDR. This is a simple library with one function which finds significant differences between two columns in a pandas DataFrame. For example, imagine you had the following data frame: Subject UK World Biology 50 40 Geography 75 80 Computing 100 50 […]
Just a quick one this time… GeoParquet is a cool new-ish format for geospatial data. I’ve tried to use it a couple of times, but always run into issues with my GDAL/OGR install not supporting it. Each time this has led to me giving up, as I couldn’t be bothered to install GDAL from somewhere […]