A summary of work I've done at the Space Telescope Institute.

Back Filling

I modified the code to test for the case when two images do not overlap and then short circuit the execution. I'm testing the change.

Posted on 30 Sep 2014

Bad Data?

I'm looking for the source of the error in doblot. It looks like the pixmap itself has bad data, which would be a result of a bad WCS in the test files. I will need to investigate this further.

Posted on 29 Sep 2014

One Down, at Least One More

I found the error in the drizzle code, which was an attempt to access beyond the end of the input image: [1023,1024]. I still have a problem with blotting crashing in5 out of 15 test cases. This is odd because it doesn't happen near the edge of the imge, it's at pixel [999,575].

Posted on 26 Sep 2014

More Error Hunting

I tried to characterize the errors by determining what tests caused which methods. After talking with Christine, I decided to ignore the official logging and add my own. I tracked the error to an attempt to access pixel [1023,1024] , which looks like the image bounds aren't being computed correctly.

Posted on 25 Sep 2014

Hunting for Errors

I spent the day trying to figure out the rather cryptic error messages and find more information. All I know so far is that one error (-11) is generated in turbo mode and the other (-6) when writing files.

Posted on 24 Sep 2014

Moving Again

With Christine's help I was able to continue regression testing and resolved three problems with the drizzlepac code.

Posted on 23 Sep 2014


Had trouble figuring out why drizzlepac wasn't found by the regression tests. Will ask Christine's help tomorrow. I went back to studying and writing some trial Cython and C interface code. 

Posted on 22 Sep 2014

Phase 2

I revised my unit tests and convinced myself the problems were caused by edge effects. No code change needed. I started running the regression tests and fixing the problems reported.

Posted on 19 Sep 2014


I did some more calculations using the drizzle handbook formulas to see if I could make sense of my results. Everything checks out against the code. I started setting up the regression tests. I copied the files over but did not get beyond that. I wrote down some of my notes for the fields in th p structure as a start to documenting the code.

Posted on 18 Sep 2014

Cleaning Up

I restored the ability to subset the image being drizzled even though the code does not currently use it. I cleaned up stuff for subversion, getting ready for the big merge. I checked the code against the Drizzle Handbook and it matches the formulas in there. But I still have some qualms about how the code works and will do a few more tests.

Posted on 17 Sep 2014