Elevation statistics of traced polygons

I wanted to find the mean, min, max, stddev elevation of a bunch of traced terraces, but this can be done with any input files of a zone dataset (i.e. shapefile of polygons) and a value raster (i.e. raster of elevation values). 1. Make the zone dataset, in my case, make a shapefile of polygons [make polygon layer] 2. Add field(s) to the Attribute Table to define the zones. I have a separate ID

make polygons

To make some @#$*%$@#% polygons in arcgis (e.g. trace fluvial terrace deposits): 1. Open Arc Catalog 2. In the Location bar, navigate to the folder where you want to put the polygons (shapefile) 3. File -> New -> Shapefile 4. Name it and choose Feature Type -> Polygon 5. If you want, edit the Coordinate System Select -> Projected Coordinate Systems -> (UTM NAD 1983 10 N for local stuff) In

obtain and view seismic data from IRIS

This is deteriorating from a pedagogical tool to a storage place for cryptic notes. But, better than nothing. One way to get some seismic data from IRIS and look at it 1. Use the GMAP (google map) interface on the IRIS site http://www.iris.washington.edu/gmap/ The instructions tell you what to enter in the URL lat/lon example: http://www.iris.edu/gmap/?minlat=46&maxlat=49&minlon=-125&maxlon=-

hillshade from seamless data

It's ArcGIS time. First, let's reflect on how Arc is the anti-google in terms of user-friendliness. It's a constant source of exasperation and I am here to document my exasperation and hopefully avoid some in the future. Starting from the beginning, here's an example if you want to download high resolution topographic data (1/9 arc second, where 1 arc second at the equator is ~31 m)  from the

LaTeX on windows

Matlabor is back, but not only about matlab. It's a place to put things that I would otherwise forget. Today we're going to document how to do LaTeX on windows. Why? Let's just assume the following (1) I had ubuntu working but when I tried to upgrade it yesterday, I ended up three hours later very demoralized with no more ubuntu on my computer (the fault of incomplete wubi uninstall, and my

profile & tic & toc

it seems like i have exhausted my knowledge of matlab functions. i am still waiting for guest blogs for patch and ode45. i won't hold my breath. or perhaps i will. here's something pc told me about once, i haven't used it much because my programs aren't that intensive. (not intensive for the computer, but very intensive for me to produce) profile The profile function helps you debug and

textread and ignoring columns

okay, say you have a .csv file (comma separated variable, excel likes those) and for come reason you don't want to use csvread. i found textread to be more flexible. roka collected some data that has 22 headerlines, and then 4 columns of data. i only care about the first column of data. so this is what i used to read in the file: [kilograms] = textread(namestr,'%f %*f %*f %*f', 'delimiter', ',',

break your plot. breakplot

there are several options on file exchange for putting a break in your plot axis if you have a region of uninteresting data. for example if you have 12 subplots and 11 of them have the same y-bounds, but one of them has a very high value, you can put a break in that plot and standardize the rest of the axes bounds. got it? breakplot breakxaxis (you can modify it so it's the y-axis) i haven't

fread: read binary data

probably the moment that i felt like the biggest matlab stud (although there are so many i cannot even count, haha JOKE), is when i finally decoded the binary data from the laser scanner my flume. the folks at SAFL had written the program to store the voluminous data in binary format, and ever since dec. 2006 i knew that one day i would have to figure out how to read it. fread reads data from a