Wolfram Mathematica

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10:34 AM

ImageCorrelate[
   Image[CenterArray[1, {3, 3}],
    "Bit"], {{0, 1, 0}, {1, -1, 1}, {0, 1, 0}}] //
  ImageData // InputForm

(* {{1.4901161193847656*^-8, 0.9999999403953552, 1.4901161193847656*^-8}, {1., -1., 1.}, {1.4901161193847656*^-8, 0.9999999403953552, 1.4901161193847656*^-8}} *)

I can't really call that an expected result.

kirma

11:33 AM

I'm not entirely certain if that should be reported as a bug or not.

It would seem "Bit" type is cast to "Real32", which is an anomaly in comparison to other types, and also doesn't produce as good rounding as possible.

4 hours later…

ZeitPolizei

3:38 PM

Is there a good way to add certain keywords to an existing question so that it is easier to find by searching?

in particular this question: mathematica.stackexchange.com/questions/8382/…

i was looking for "unpacking list in anonymous function", but only found that question via detours.

One idea would be to just make a new question, and then immediately close it as duplicate. but I'd assume there's a better way?

C. E.

@ZeitPolizei By "unpacking" you mean what is called "destructuring" in that question?

I'm not so sure it's a good idea to add the keyword "unpacking" because it means something else in Mathematica. Unpacking a list is when you do an operation on a list which forces it to change its internal representation to a more inefficient data structure, which consumes much more memory.

ZeitPolizei

3:58 PM

@C.E. yes unpacking in Haskell == destructuring in Mathematica
Hm, I see the problem.

if one added a comment to the question along the lines of: in Haskell this is referred to as unpacking, would that already help with the search results?

C. E.

@ZeitPolizei It depends on how many Haskell users we have on the site, for whom "unpacking" means "destructuring". But it would be a nuisance for everybody else because that question would come up in the search results when they were searching for questions about unpacking lists, in the Mathematica sense.

Also if you search for "unpacking a list" you won't find that question, because it will be buried in a heap of answers about packed lists.

ZeitPolizei

ok, looks like there isn't really a nice solution for this. ideally a resource like "Mathematica for Haskell programmers" would exist somewhere…

3 hours later…

Szabolcs

6:51 PM

@ZeitPolizei "Coming soon", supposedly — wolfram.com/language/fast-introduction-for-programmers/en

1 hour later…

William

8:19 PM

How do I scroll to bottom of output in mathematica?

on print or cell execution?

automatically on cell evaluation that is

... mathematica.stackexchange.com/questions/135892/…

Michael Hale

@William I haven't thought about that. It moves the cursor to the end automatically, so I typically just press an arrow key after evaluation to scroll to the cursor.

2 hours later…

Emilio Pisanty

10:30 PM

Is @halirutan around?

I was wondering what your thoughts are on the goo.gl url shortener thing

William

11:06 PM

@EmilioPisanty link I'm interested

depending on what you mean

Emilio Pisanty

A: New SE-Tools - formerly known as SE-Uploader

I have a bug report: since recently, Stack Exchange is banning the use of the goo.gl address for the decoder. For some time I've been sharing notebooks by including the line Mathematica code through Import["http:// goo.gl / NaH6rM"]["http://i.stack.imgur.com/wM9dN.png"]</sup> under the im...

William

that is a problem hmmm. halirutan is the right person to talk to

Emilio Pisanty

@William I imagine (s/?)he's seen it, since the question is his so he'll have been notified, but he hasn't responded there.

halirutan

Give me some minutes.. Im here soon

halirutan

11:37 PM

@EmilioPisanty "She" definitely hasn't seen it :)

Emilio Pisanty

@halirutan good to know. I defaulted to the avatar ;-) but happy to be corrected.

Anyways, yeah, you can't copy-paste from the notebook upload directly into an SE answer

halirutan

@EmilioPisanty My thoughts are the following. We have 3 choices I guess.

The obvious first choice is to use the full url.

Emilio Pisanty

@halirutan that's a good deal too long, I feel

halirutan

Then we have the solution that I create a decode.halirutan.de which has the disadvantage that my site needs to be up and running for the rest of earths time

Emilio Pisanty

maybe we can ask SE to sync that file to https://stackexchange.com/SEImageExpressionDecode.m

halirutan

11:43 PM

The last thing is that we test whether SE banned pastebin links.

Do you know that? Are we still allowed to use pastebin and friends?

Emilio Pisanty

@halirutan that's easy enough to test

but I'm afraid it's a patch and may only be a temporary fix between now and when they ban whatever alternative we went to

I would say that we need to talk to the devs that made this change to understand its scope

pastebin seems to be OK for now btw

halirutan

@EmilioPisanty I'm not sure it would be a temporary fix. Banning URL shorteners is one thing, but banning a code paste site on a programming platform?

Emilio Pisanty

@halirutan hmmmm, ok

halirutan

@EmilioPisanty Anyway, the solution is simple. We decide what to do and I'll patch the software.

Emilio Pisanty

@halirutan maybe halirutan.github.io/SEImageExpressionDecode.m?

halirutan

11:48 PM

@EmilioPisanty Yes, that would be an alternative too

Emilio Pisanty

it gives you full control of the file and it's as dependable as the current solution

and it's sort of manageably short, I guess?

longer than the goo.gl version but less likely to completely break lines than the current raw.github version

halirutan

@EmilioPisanty Let me think about this. I'm coming back to you when I decided what to do.

Emilio Pisanty

@halirutan cool, yeah, no pressure ;-)

I just wanted to make sure that you were aware of it.

halirutan

@EmilioPisanty Yes, I have seen it. See you later.

Emilio Pisanty

@halirutan btw d'ough, just saw your name on your personal page

halirutan

11:51 PM

@EmilioPisanty Yep. I don't make much effort to hide who I am.

Emilio Pisanty

@halirutan oh, no worries. I just try not to assume genders online unless it's blindingly obvious.

@halirutan also, feel free to edit in a "this has been fixed" message on that answer on meta, if you feel that that's the most appropriate way to mark that.

I guess I shoulda posted it here

Q: SE-Uploader: Safety issues when sharing code

Background Some might have noticed that I was working on completely revising the SE-Uploader. I will make a separate thread about this, but an important change is that we can now share Cells or Notebooks as easy as it is with images. If you want an example evaluate the expression below: Import[...