r/QGIS

Hi! I’m in the research phase of writing a book about a ghost town in eastern California. As part of it, I want to create accurate maps of the town and its mines.

For the mines, I have been using the USGS MRDS database, which is unfortunately inaccurate in the area, so next time I’m there, I’ll be getting GPS coordinates on all the mine features. This is within my capabilities to do.

What’s a bit beyond my capabilities is the town itself. I plan on finding foundations and comparing those to historical photos (of which there are few.) There are very few structures left. I got the USGS lidar data, but filtering out the vegetation in the area is difficult because it’s largely sagebrush, and I am a complete novice at this.

Can anyone suggest methods for finding the locations of historical buildings (town was active until 1915ish) either using publicly available data or other methods? It would be an absolute amazing help in getting my book up to the quality I want.

I just need someone to tell. I’m quite experienced with tech. I have a specialization in software engineering, an undergrad degree in CS from a top tier university, with another Major in Urban Planning where I even previously took a GIS course couple years ago. Ive studied intermediate level SQL, Programming, Numerical Analysis, etc. I’ve fixed computers and taught computer software (like MS Office) as a job (IT Helpdesk, GeekSquad etc). I was doing a technical assessment interview today for a GIS job I Really wanted. So I prepared like Crazy.

They said it’ll be on ArcGIS.

I use Linux myself. So I decided to practice it all using QGIS. I went in depth. Being a CS specialist (having taken intermediate courses on SQL, Python etc), I studied attributes table joins, merges, spatial joins, buffers, everything. How to write python expressions, etc. I reviewed till I fully understood everything, including projections, raster data and what not. I exclusively worked with shape files in QGIS but fully understood the different file formats, even .dbf, .prj and what they’re used for.

I spent the last 2 days before the interview with ArcGIS, basically know how to use it. All the concepts were the same. I was ready. With ArcGIS I decided to work with geodatabases and saving feature class in the .gdb files. After all, I had so much practice with shape files in QGIS. I was ready for an intermediate, maybe even advanced test.

I go into the interview. Naturally I’m nervous but hey I was ready. Easiest questions Ever. “Hide this layer, label that layer, create a layout with a legend”. The most advance thing was to use the Clip tool (literally the only non-Super basic thing). But then…

Early into the test: very easy working with layers, and then the question I got stuck on. “Save this layer as a shape file”. Easy, right? Data -> export…. And…. No shape file option? Uhm ok, I can figure this out. I click on browse, and try to change the file format, but shape file isn’t showing up in the list of formats. Ok, surely this isn’t That hard, I think. I change directories, and still, no shapefile option. The Only Option is geodatabase… I think, maybe I should name it layer.shp, but I know that even if you suffix the file name a certain extension, how I save the file format is what takes precedence, and the only format for saving was geodatabase. Maybe there is a separate button in the menu / ribbon for it? Nope. Maybe it’s in the right-click options? Nope. At this point I Am Shocked. How in the world is saving a shape file using ArcGIS NOT intuitive? I don’t want to risk naming the file one thing but specifying the format another, so I panic. Because I know if I do that and the files don’t open, it will mess up everything else. I save it as a feature class in the .gdb. Multiple questions pop up about saving layers as shape files. For all of them, I couldn’t do it, didn’t know how. I finished the entire interview, and not One shape file saved. I left a note on the questions saying “out oh habit I saved it as a feature class in .gdb since it’s cleaner, and that my data is there D:” I think I wrote I read to save it as shape files afterwards near the end. Idk

I look it up after the interview, frustrated. And turns out, it’s the most unintuitive thing ever. Apparently you have to switch directories, say you want to save it as a geodatabase but append .shp to the end of the file name. I went in not actually searching how to save as a shape file in ArcGIS because I thought it was intuitive, and that’s what messed me up. Intermediate / Advanced level knowledge, and yet I failed the most basic interview because saving as shape file is what I couldn’t do.

If only it was as intuitive as QGIS. Anyways, thanks for reading.

I just wanted to share an IRC channel for all things GIS related. Of course this channel isn't official in any way but just thought IRC is a great platform to share here. This IRC network has mostly opensource contributors and those who come from a computer science/IT background but GIS professionals and folks interested in GIS are more than welcome to join.

For those interested:

main website: https://ouch.chat

IRC channel: #gis

QGIS plugin · ArcGIS Pro toolbox · Python · open source,

https://github.com/Praddy-GByte/basinkit

Anyone doing watershed, hydrology, geomorphology, or terrain work who would rather start with a finished basin than spend an afternoon assembling one:

Every time I needed a catchment, the workflow was basically the same — find a DEM, fill sinks, compute flow direction, delineate the basin, then find land cover, soil, and rainfall datasets and clip everything to it.

So I built basinkit.

Click a point on a river and it returns the basin draining to that point, with:

• elevation
• land cover
• soil
• rainfall
• surface water
• river data
• basin morphometry
• the river's longitudinal profile

Everything is already clipped and masked to the basin.

No account, login, or credits required. It's free and MIT licensed.

One important limitation: it works much better for large basins than very small ones. In blind validation against 2,550 gauges across 99 countries, median area error was 0.3% for basins above 100,000 km², but 181% below 100 km².

You can find it by searching “basinkit” in the plugin manager.

Code/docs:
https://github.com/Praddy-GByte/basinkit

Bug reports are very welcome — I'd especially like to hear where it breaks or gives you questionable results.

https://preview.redd.it/l9v1dvahb1th1.jpg?width=1080&format=pjpg&auto=webp&s=937e6cfd90828c6370bb21bffcd55fd0a6fe68d3

I am running the latest archlinux and QGIS (4.2.2-1). I have the Google Earth Engine plugin installed but I get this error when it starts up:

ee.ee_exception.EEException: Project <name of project> is not registered to use Earth Engine. Visit https://console.cloud.google.com/earth-engine/configuration?project=<name of project> to register your project. See https://developers.google.com/earth-engine/guides/access for more details.

I've tried using the git version but that doesn't work either. My only assumption is it keeps pointing to an old project or pointing to a google account that it isn't registered to? Also, I know that GEE isn't friendly with archlinux's python path. I'm kind of lost on this issue and need a little guidance on how to fix it.