1. better map projections
2. geo-browser export (i.e., to Google Earth, etc.) (exporting from ENVI, discussion of doing it in IDL)
3. stereo display (simple anaglyph system, I also have code for using Alioscopy’s autostereoscopic monitors from IDL object graphics which I have not published yet)
4. a better widget system (a way to make IDL bindings for Qt?)
5. easier runtime distribution (MAKE_RT über-installation)
6. better handling of large data sets
7. better support for databases
8. integration of GPU and parallel processing (Tech-X does both GPU and parallel processing in IDL)
9. OPeNDAP support (I have something coming soon for this!)
10. easier interface to gridding data
11. ability to read Matlab “.sav” file
12. better volume rendering

Thoughts? Did we miss something crucial?

Full disclosure: I work for Tech-X Corporation and have worked on GPULib, FastDL, and the Remote Data Toolkit.

Just one word: Wow!

It appears that the promise of IDL 5 has finally been realized. :-)

David also posted a longer description of the new features, so I won’t go through the laundry list (but I do intend to run through it with some examples when 8.0 is actually released, like I did for 7.1).

But I will discuss a bit the one feature that I have used extensively: operator overloading. This was the main focus of my talk about GPULib with IDL 8.0. The gist is that GPULib variables will be objects and if you are running IDL 8.0+, you can do things like the following:

IDL> a = gpuFindgen(10)
IDL> b = gpuFindgen(10)
IDL> c = a + b

This was easy to implement, just inherit from IDL_Object and write a method with the special name _overloadPlus:

function gpuvariable::_overloadPlus, left, right
  compile_opt strictarr

  return, gpuAdd(left, right)
end

Most operators are supported like +, -, /, *, MOD, EQ, etc., but also including brackets (both on the left side and right side of an assignment) and other special methods used by PRINT, HELP, and SIZE. The dot operator is automatically connected to the getProperty and setProperty methods of the class.

Another nice point is that GPULib will not require separate versions for pre-8.0 and post-8.0 versions of IDL. Just write a simple dummy IDL_Object class. This will allow the code to be compiled in versions of IDL before 8.0 and won’t be found (because the real IDL_Object is part of IDL’s core and found before any user routines) in versions 8.0+. Of course, only the old procedure or function interfaces are available in versions before 8.0. I’m much more likely to use operator overloading because I can provide extra features for IDL 8.0 users and fall back to a more verbose interface for those who have not upgraded yet.

If you have the tech preview handed out at the meeting or are just interested in some more examples of this, check out these HDF5 classes which make use of operator overloading. The end of the mg_h5.pro file has a main-level program which shows how to use the classes:

IDL> .run mg_h5

Full disclosure: I work for Tech-X Corporation and have worked on the IDL bindings for GPULib.

More thoughts about the meeting to come…

1. Added an extra argument to ASSERT which can be inserted into the message via C-style format codes.

2. Added XML and JUnit output formats (and corresponding XML and JUNIT keywords to MGUNIT to turn them on).

3. Added ability for a test to determine if it should count in the final results tally, i.e., if it is “skipped”. Use the SKIP keyword of ASSERT to skip a test instead of failing it if the condition is not met.

4. Fixed memory leak.

Both 1. and 3. involve more parameters for ASSERT.

For example, it can be handy to produce error messages containing values from local variables, but it is painful to have to use STRTRIM or STRING to format the message nicely. The following ASSERT call will insert the values for result and standard into the appropriate locations in the message:

assert, condition, 'incorrect result, %f; expecting %f', $
        result, standard

You can pass up to three values this way.

Skipped tests allow a test to determine if it should be run and counted in the total number of tests. For example, in GPULib there are many tests which test double-precision calculations, but these are only valid if the GPU is capable of double-precision. Previously, these counted as failures and we just had to know that passing 150 out 200 tests was “OK” if the GPU was not double capable. Now these tests can be skipped with the following:

assert, gpuDoubleCapable(), 'CUDA device not double capable', /skip

A skipped test will not count the total number of tests (though it is indicated afterward, i.e. “3/4 tests passed, 2 skipped”).

This event is designed to bring together IDL and ENVI users to provide opportunities for networking, sharing ideas, and working on strategies that advance our scientific data analysis and visualization community. We hope you will join us for one or two full days of presentations from professionals in a variety of industries who use visualization technologies for a wide range of applications.

ITT VIS is now accepting abstracts for talks. Pre-registration is required to attend and there is a $40 per day fee.

Of course, 3-dimensional viewing available on Bing was not supported for any of the browsers on my Mac (Firefox and Safari)…

Matplotlib for Python Developers by Sandro Tosi is a welcome addition to my bookshelf. It focuses on embedding Matplotlib in applications in GTK+, Qt 4, wxWidgets, and even various web frameworks such as Pylons and Django. But the fundamental elements of the scientific Python tool chain, such as NumPy and IPython, as well as a thorough tutorial of Matplotlib itself are discussed. Both the pylab/pyplot procedural interface (useful for interactive plotting) and object-oriented interface (useful for fine-tuning and more advanced usage) are covered. Over 2000 lines of example code are downloadable from the book site.

Seeing as I don’t use Matplotlib regularly, I’m sure I will using this book frequently to brush up on Matplotlib basics. And this book would have saved me a lot of time when I was writing my only major Python project, a PyQt 4 application which embedded interactive Matplotlib graphics. While this book doesn’t cover every detail of Matplotlib (the online docs are good for that), it will get you started no matter how you are using it.

The publisher has made a sample chapter on embedding Matplotlib in Qt4 available for download. More information, such as a full table of contents, is also available on the publisher’s site.

Full disclosure: I received a review copy of this book.

Link via WeLoveDatavis.