Gorilla Food Plants Biomass and Ranging

The last two days, I have been working with Olivier Jean Leonce Manzi here at Karisoke Research Center on the question of the relationship between gorilla food plants biomass and the ranging patterns of gorillas outside Volcanoes National Park (VNP) in Rwanda. Even though Volcanoes National Park is set aside and gorillas thrive inside, they don’t strictly stay within the bounds of the park — … Continue reading Gorilla Food Plants Biomass and Ranging

A little Gorilla Time

I miss my mountain gorilla friends in Rwanda. Let’s write a little more code to support them. I’ll be visiting Karisoke again next week, so it seems timely to post a little more code (HT Jean Pierre Samedi Mucyo for working with me on this one). The problem today is simple — given a time series of gorilla locations and dates, can we calculate rate … Continue reading A little Gorilla Time

Uninformed botanical musings

I had the good pleasure of attending FOSS4G Seoul. One of the organizers (Heegu Park) early on told me, in response to the workshop I planned, something to the effect of “Whatever you need, Steve, ask for it. Nothing is impossible.”  The organizers truly were capable of fulfilling any request.  More on that later. Last time I was in Seoul, I took lots of pictures. … Continue reading Uninformed botanical musings

Landscape Position using GDAL — PT 3

More landscape position pictures — just showing riparianess. See also https://smathermather.wordpress.com/2014/11/22/landscape-position-using-gdal/ and https://smathermather.wordpress.com/2014/11/24/landscape-position-using-gdal-pt-2/ Map tiles by Stamen Design, under CC BY 3.0. Data by OpenStreetMap, under ODbL Continue reading Landscape Position using GDAL — PT 3

Landscape Position using GDAL

Hat tip again to Seth Fitzsimmons. I’ve been looking for a good, easy to use smoothing algorithm for rasters. Preferably something so easy, I don’t even need to write a little python, and so efficient I can run it on 30GB+ datasets and have it complete before I get distracted again by the next shiny project (a few hours). Seth’s solution? Downsample to a low … Continue reading Landscape Position using GDAL

Kicking the tires of PostGIS 2.0 — Testing ST_MakeValid

The feature in PostGIS 2.0 that excited me most was not topology support, raster support, or 3D functions.  Ok, raster was near the top of my list.  But what I was really excited by was the ST_MakeValid function.  Sad, isn’t it?  Lack of vision probably– excited to try to solve recurring technical snafus in a computationally inexpensive way, rather than being more excited by the … Continue reading Kicking the tires of PostGIS 2.0 — Testing ST_MakeValid

GDAL Slopes– Local Hydrologic Slope vs. the Standard Approach

Open Source software is not, of course just about warm and fuzzies, great support, rapid development cycles, shared costs, etc., it’s also about getting your hands dirty with someone else’s code and implementing stuff more quickly and more intelligently because of it, and hopefully learning something in the process.  You don’t have to poke under the hood to drive the car, but sometimes it’s nice … Continue reading GDAL Slopes– Local Hydrologic Slope vs. the Standard Approach

Landscape Position: Conclusion? (part 2)

From earlier post: “I’ve managed to pilot most of a fast high resolution landscape position workflow with PovRay as my magic tool. The final steps I hope to pipe through PostGIS Raster. In the meantime a screenshot and description: blues are riparian, raw ocre, etc upland categories, grey is mostly flat lake plain and mid slopes, all derived from just a high res DEM input … Continue reading Landscape Position: Conclusion? (part 2)

Landscape Position: Conclusion?

I’ve managed to pilot most of a fast high resolution landscape position workflow with PovRay as my magic tool. The final steps I hope to pipe through PostGIS Raster. In the meantime a screenshot and description: blues are riparian, raw ocre, etc upland categories, grey is mostly flat lake plain and mid slopes, all derived from just a high res DEM input (no hydro lines … Continue reading Landscape Position: Conclusion?