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visits member for 2 years, 7 months
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Mar
19
comment Encoding format used by GraphicsData?
Very cool. Just for reference, what's str a picture of? I'm trying to use imagemagick to convert ~/Desktop/foo.pict to something else, and it's showing up as a 232x75px black box. Is that correct?
Nov
6
comment Simple Solve example fails: why?
@MichaelE2 I see, so an explanation for Solve better than the documentations "Solve[expr,vars]` attempts to solve the system expr of equations or inequalities for the variables vars." would be "Solve[expr,vars] attempts to find replacement rules for the symbol(s in) vars which cause the statement expr to be True".
Oct
19
comment Ways to compute inner products of tensors
@Jens Doesn't this waste memory in a huge way because the calculation stores the tensor product as an intermediate value? Or does TensorProduct have a special UpValue or something...
Oct
12
comment Printing Block Matrices
Awesome, thanks. I put my edit in before I saw your example, and I see we came up with similar examples. The matrix I actually want to print is too unwieldly to copy here.
Aug
23
comment Determine whether some expression contains a given symbol
-1? Sure the answer is obvious once you know it, but I spent a very long time looking for an answer, and even longer trying to code my own answer. It's not like FreeQ is a terrible descriptive function name, and it's not listed in the 'Patterns' Guide, or the 'Testing Expressions' guide, or a bunch of other guides that might seem relevant to a newish user.
Aug
19
comment Implementation of builtin function Fold
That's great, thanks!
Aug
19
comment Implementation of builtin function Fold
@NasserM.Abbasi: Sure, but I asked the question because in this case a piece of the internal implementation does matter; if it were done in one way, I would run out of RAM, and if it were done in another, I wouldn't.
Aug
19
comment Implementation of builtin function Fold
Thanks for the implementation example R.M, but I was more looking for a test than an example.
Jun
22
comment Outline around sphere
@jVincent, that looks really good, thanks!
Jun
22
comment Outline around sphere
@J.M., Yeah, I may end up settling for this. There are just a lot of spheres in a 3D array (diamond lattice, actually), and I wouldn't mind something a bit more striking.
Jun
18
comment The difference between 0. and 0
@Jens, @Pillsy, thanks. I arbitrarily choose this as the correct answer. I have chosen to add the line F[A___, a_?(Equal[#, 0] &), B___] to be safe: I do not want to cut off at less than 10^-10.
May
3
comment What does the slash-colon symbol do?
Thanks @nikko. What purpose do the x and y serve in this example? It seems to work without them.
May
3
comment What does the slash-colon symbol do?
@LeonidShifrin, With the help of this post I was able to parse your comment and I now understand; thanks.
May
3
comment What does the slash-colon symbol do?
@J.M.,@R.M,@kguler: Thanks for the tips, I didn't know about the F1 thing. Having read those documentation pages, I still don't understand the difference between my two lines of code.