10,561 reputation
22153
bio website
location Munich, Germany
age 36
visits member for 2 years, 8 months
seen 2 hours ago

I work at a small mechanical engineering company, where I develop software and image processing algorithms for camera-based inspection machines.


Jul
4
revised Why are functions called first-class objects in Mathematica?
added 35 characters in body
Jul
4
comment Why are functions called first-class objects in Mathematica?
@Eric: I've added a new paragraph about how "variables" and "functions" are basically treated the same way.
Jul
4
revised Why are functions called first-class objects in Mathematica?
added 1754 characters in body
Jul
4
comment Why are functions called first-class objects in Mathematica?
@Eric: I didn't doubt that you can parse the expression tree. A C programmer can parse expression trees, too. The point is: The C programmer will rarely handle expression trees at runtime, unless she's writing a compiler. In Mathematica, you handle expression trees all the time.
Jul
4
comment Why are functions called first-class objects in Mathematica?
@acl: The documentation is great once you get the computational model. But I must admit that I had a lot of trouble understanding it at first, when I started with all the (mis)conceptions about what expressions, functions and values are, coming from C++.
Jul
4
answered Why are functions called first-class objects in Mathematica?
Jul
4
comment Why are functions called first-class objects in Mathematica?
Try to parse the expression x=(Sin + Cos)[a] - are Sin/Cos values or functions here? They're added like values, after all. Is Plus a function? Since it is "called" with [a]. Now call Through[x], and you'll get a perfectly sensible mathematical expression. Being able to manipulate expression trees like that is extremely useful.
Jul
2
awarded  Curious
Jun
18
awarded  Nice Question
Jun
18
revised How would you efficiently implement BinListsBy?
Added timing for Mr. Wizards version
Jun
18
accepted How would you efficiently implement BinListsBy?
Jun
16
comment How would you efficiently implement BinListsBy?
@Mr.Wizard is right, I'm not looking for a "presentation" solution, but one where I can process the resulting lists further. I wouldn't mind modifying the code to do that, but even if I strip away the strings and TableForm's, it adds a number to each result list, and I'm not sure if it will always be the first element (so I can remove it easily)
Jun
16
revised How would you efficiently implement BinListsBy?
More timings
Jun
16
comment How would you efficiently implement BinListsBy?
@Mr.Wizard: I'm trying to, but I honestly don't understand it well enough. To compare the timings, the function should take a function parameter, like the other versions. Yours (I think?) always gathers by the first subelement, which may or may not be faster than calling a user-supplied function.
Jun
15
answered Moment central of a binary image
Jun
11
comment How would you efficiently implement BinListsBy?
@Szabolcs: My actual purpose is to create a "weighted histogram", of e.g. gradient orientations, weighted by gradient strength of every pixel in an image. As in mathematica.stackexchange.com/questions/23602/…. So yes, the data will probably be packed
Jun
11
awarded  Self-Learner
Jun
11
revised How would you efficiently implement BinListsBy?
timing measurements
Jun
11
revised How would you efficiently implement BinListsBy?
typo
Jun
11
answered How would you efficiently implement BinListsBy?