Domain: wavemetrics.com
Stories and comments across the archive that link to wavemetrics.com.
Comments · 10
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Re:MATLAB on OS X won't suck now?
Perhaps use the lower-cost, well-supported Igor Pro, instead? http://www.wavemetrics.com/ Disclaimer: I work there
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Orientation analysis in an image
The image analysis question is interesting. You are trying to read dial positions, so conventional OCR is probably useless (unless there is a package to do exactly that?).
What you can do is use image processing commands (in your favorite programming language; a shell script, Python, etc.) to crop the image to generate a small image for each dial. Then convert to grayscale (and maybe increase the contrast to highlight the dial). To then calculate the preferred orientation in the image, you calculate gradients along different directions. There will be a much higher value for the gradient along directions perpendicular to the preferred axis. This procedure is described very briefly in this paper:
Harrison, C.; Cheng, Z.; Sethuraman, S.; Huse, D. A.; Chaikin, P. M.; Vega, D. A.; Sebastian, J. M.; Register, R. A.; Adamson, D. H. "Dynamics of pattern coarsening in a two-dimensional smectic system" Physical Review E 2002, 66, (1), 011706. DOI: 10.1103/PhysRevE.66.011706
This is easiest to do if you use a graphics package that has directional gradients built-in (but coding it yourself probably wouldn't be too hard). Basically you create copies of the image and on one you do a differentiation in the x-direction, and for the other one a differentiation in the y-direction. Let's call these images DIFX and DIFY. Then you compose two new images:
NUMERATOR = 2*DIFX*DIFY
DENOMINATOR = DIFX^2-DIFY^2
Then you calculate a final image:
ANGLES = atan2( NUMERATOR, DENOMINATOR )
(All the above calculations are done in a pixel-by-pixel mode.) The final image will have an angle map (with values between -pi to pi) for the image. It should be easy to then use the avg or max over that image to pull out the preferred direction. You may also improve results by tweaking the initial thresholding, or by adding an initial "Sharpen Edges" step, or by blurring the NUMERATOR and DENOMINATOR images slightly before doing the next step.
In any case, the above procedure has worked for me when coding image analysis for orientation throughout an image (coding was done in Igor Pro in my case). So maybe it is useful for you. -
Science?Creative arts yes, science? I'm not so sure. Having worked in science in academia and industry, all the work is done on PCs and a little on SGis. The only Mac I used was an ancient thing that had some PCR simulation software from the early 90s (I think). Oh, and Igor Pro http://www.wavemetrics.com/ for electrophysiology but that was moving towards PCs when I left anyway.
Anyone know of any current Mac science applications?
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Re:million-row spreadsheets
How about data analysis software geared for scientists such as Matlab or my favorite, Igor Pro?
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Re:Don't Forget The Cool Factor
Of course, I was not entirely innocent in posting this article. Eric Heller is a friend of my Ph.D. adviser, and he is also a very famous scientist (he famously formulted the "semi-classical approach to spectroscopy", see p. 368). He is a big advocate of visualization precisely because it can make getting the point across more easily. My claim to "fame" in visualization can be seen here and here. (Obviously, I like Igor Pro.) In the case of my own work, I like to think that the contrast in the nice 3-D surfaces shows the viewer that something important is going on (energy transfer). The meat of the argument comes from taking the slices of the pictures and doing curve fitting, and fitting the results to established theories, but people can read on for that stuff. it is awfully nice to get the point across in one or two pictures.
If you ever have the pleasure of attending a Heller talk, you will see how he uses the nice pics as an overview of the results, and proceeds to dig deeply. And, that's actually the point. The picture should get a valid physical picture across. It is difficult to suffer a presentation in which the speaker is offering fancy animation after animation, none of which represents any real concept or any real treatment of the statistics behind the process being described.
The question is whether the absolutely fantastic hardware and software tools that are available to scientists are being put to good use to get a fair, realistic picture across to the readers. -
Re:Science's dependence on MS OfficeI am also a scientist. Much of the work that I do is contract research for the government. Most agencies that I have encountered require regular reports in MS Word format. This requirement is typically incorporated into the language of the contract. The primary problem with MS Word on the Mac is their horrid rendering of emf graphics, and their refusal to provide WYSIWYG eps graphics on either platform. This effectively means that there is no good cross-platform answer for vector graphics if I am forced by my customer to work in Word.
Fortunately, they don't dictate how I analyze my data. My preferred data analysis & plotting package is Igor Pro, and it works really well in OS X.
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Re:Konfabulator yes. Other UI innovations?
Well, without knowing how significant something has to be before you'd label it a "revolution", it's a bit hard to answer that question.
Fair point... I guess for one thing, Tiger claims to have fully integrated voice input. If it works, cool. I may not want to talk to my computer all the time, but this could eliminate some keyboarding and mousing.
I think that back in the days of yore (Macintosh Programmer's Workshop), Apple had integrated some sort of command-line helper to assist in setting command line options. MPW as I recall was similar to the Unix CLI, but just different enough to trip you up. I didn't use it, so I don't know if it was actually useful.
Automater might impress me when I finally get my hands on it.
Microsoft's attempts to improve the UI (clippy, bob) might be along the lines, if they were much more intelligent... I realize that's a rather silly thing to say...
Here's an interesting parallel: if you have ever used Igor Pro, one of the neat features is that when you do something to a window using the GUI, it can generate the equivalent CLI text for you. That makes it easier to figure out how to script actions for repetition.
I guess I should think about it some more.
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Re:Ever since Igor
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LabVIEW also runs on OS X
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Re:IGOR
I see the academic pricing, but I find no mention of an $85 student price. Do you have a link?