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WUSTL-GIS-Programming-spring-2014 / classinfo

Class information including syllabus
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Assignment10 NDVI #17

Closed fbaum closed 10 years ago

fbaum commented 10 years ago

Do we use the same single-band images (faustRed, faustIR) that we used in Assignment 5 or were you going to send us a new multi-band image?

Nancy-Cole commented 10 years ago

Should we go ahead and begin working on the assignment? Or will you be providing us with more information, such as data and the beginning outlines of a Python script?

blordcastillo commented 10 years ago

I have created an Assignment10 document with some guidance. You can use the two single-band images, or on Monday I will produce a four band tif that can be used as well.

gis310sp14im commented 10 years ago

Are we going to have Office Hours tonight? I am not getting very far with this. I cannot figure out how to access rasters inside of a file geodatabase like in Assignment 5, and when I try my program with another raster I have around, it doesn't "look" right.

fbaum commented 10 years ago

Ian/all, I don't think rasterio can open rasters in a ArcGIS file geodatabase. To use the single-band image rasters (faustRed and faustIR) rasters from Assignment5 for this Assignment10, I first had to export them out of the file geodatabase as TIFF (.tif) files using an ArcMap conversion tool. I forget exactly which tool, but this link might help: http://resources.arcgis.com/en/help/main/10.1/index.html#//009t00000062000000

Also, I'm expecting Brett to post a 4-band .tif file, maybe later today.

blordcastillo commented 10 years ago

Almost done with the 4-band tif

blordcastillo commented 10 years ago

Here we go: https://www.dropbox.com/s/l3zs3icbijkg80v/faust.tif.zip I have included a very sparse metadata file and a world file. Band 1 is red, Band 4 is infrared.

gis310sp14im commented 10 years ago

I did try exporting out of the geodatabase as .TIF but the program complained that there was no .shape property for the TIFs.

blordcastillo commented 10 years ago

I'll be there at 6:30 btw, probably earlier.

blordcastillo commented 10 years ago

If you are having issues with strange output, make sure that you convert the bands you read to a float type (numpy.float32 or numpy.float16, which area the same types as rasterio.float32 and rasterio.float16), and you use that same type for your numpy math, and then use that same type when you write out to a new image with rasterio.