Wolfram Mathematica

Sjoerd C. de Vries

7:00 PM

but is difficult to interpret

I read it as meaning he wants the most interesting part

not the boring zero's, but he doesn't know beforehand where the interesting part will be

That's what I wanted to solve here

R.M

Yeah, I took it to be the same, except that I considered he didn't want the boring constants, not necessarily zero... That's what I tried to show with my example in the comment that boring constants can have longer LeafCounts than the actual expression that is needed

F'x

hum, what's the community stance on this kind of questions?

0

Q: MMA "Calendar Viz" --> modular, reusable functions for structured graphics

Calendar Viz (and associated data querying and structuring) developed in MMA, is an example of a composite visualization in which many graphical elements are organized at various spatial scales. It's an example of "fourth paradigm" visual analytics - ie, data driven, rather than simulation-driven...

graphics

it's more of a call to arms or feedback, than a question

Sjoerd C. de Vries

@Fx will look at it later. First finish the discussion with rm

@RM which constant do you mean?

R.M

@Fx sorry... thought you were referring to the Q that Sjoerd and I were discussing

@SjoerdCdeVries It so happened that here the constant was zero in his example, but it could've been anything

Sjoerd C. de Vries

@RM As I understood your answer you don't do any separation of equations, right?

R.M

7:07 PM

@SjoerdCdeVries No. I merely collect all expressions that are not constants and conditions. That way, he gets a list of equations, that can be used however he wants.

Sjoerd C. de Vries

@RM Well I guess it's up to the OP to makeup what suits him most. I've been re-reading the question many times all over again and I'm still not sure what he wants, though I still tend to lean towards my original interpretation. Let's just wait this out.

Shall we delete the discussion below the answer?

F'x

@SjoerdCdeVries I second that

discussions in comments are unhelpful in the long term

R.M

@SjoerdCdeVries sure.

Sjoerd C. de Vries

OK, I'll do that then. BRB for Fx's question

R.M

@Fx I'd VtC as NaRQ

F'x

7:11 PM

@RM me too

but we have a mod around, it'd be much faster that way :)

still few high-rep users

@RM plus, I realize now it's borderline advertising

alancalvitti, San Diego

122 5

pattern-matching programming syntax graphics graphs-and-networks list-manipulation mathematical-programming

his profile says "head of research > statigrafix <" and the package he's discussing is his company's

@RM love your comment, very nicely worded by the way

R.M

@Fx Yeah, but he clearly has acknowledged that and he says "we developed", etc., so perhaps should give him some leeway. If he does this often, then Sjoerd et al. can talk to him about it

Sjoerd C. de Vries

Hmm. I already closed one of his questions. I don't like to disappoint people who might be a valuable asset to the site. But then, it clearly looks like it's narq

F'x

@RM I don't think it would hurt, if only the question was good on its own

Szabolcs

Good evening

Sjoerd C. de Vries

@Szabolcs Hey Szabolcs. Longtime no see

F'x

7:17 PM

@Szabolcs Good evening, sir

R.M

@Szabolcs Dropping in everyday to keep your count running for "fanatic"? ;)

Sjoerd C. de Vries

He lost it already

During suspension

Szabolcs

@RM I haven't been here every day, I don't think I will ever get fanatic :-)

Sjoerd C. de Vries

Well, we know you're a fanatic\

Szabolcs

:D

Just dropping in for a short time

R.M

7:18 PM

Anyway, I've got to head out. Bye all. Thanks, @Sjoerd

Szabolcs

will be full time after Easter ;-)

Sjoerd C. de Vries

What have you been doing lately?

Szabolcs

Did anything interesting happen while I was away?

Sjoerd C. de Vries

@RM You're welcome. bye

F'x

oh, so you can get voluntary suspensions like in casinos? cool

Szabolcs

7:19 PM

I was travelling a bit, in my hometown and in Hungary

F'x

noöne every got addicted to French.SE enough to require that, unfortunately

Sjoerd C. de Vries

@Szabolcs Mr.wizard is rarely here. That's, like, news

Szabolcs

@SjoerdCdeVries Oh! I hope he's alright

Did JM return?

Sjoerd C. de Vries

He missed the fanatic streak too

Mr,wiz i mean

F'x

@Szabolcs no

Sjoerd C. de Vries

7:20 PM

JM has only checked it a few times the last 6 weeks or so

Szabolcs

Next week I'll try to fix up the image uploader palette, there's a LOT to do ...

Sjoerd C. de Vries

Did you see my answer to this question?

12

Q: How can I extract data points from a black and white image?

Consider the following graph (source): Is there any way to extract the data points from this image in a semi-automatic way? I have seen, and tried the methods suggested in this question, but they did not work, as most of the approaches there utilize color contrast to extract the data; I couldn...

graphics import image-processing

The uploader had problems with copying an image of the last panel in that tabview

Szabolcs

No, I haven't had time to look at questions yet

Reading now

Sjoerd C. de Vries

@Szabolcs The graph it copies has different data points than the one in the TabView. I had to resort to Snipping Tool to make a screenshot of that tab

Szabolcs

Bookmarked, I'll take a look next week

I';ve seen this problem many times: mathematica.stackexchange.com/questions/3943/…

but got to go now

bye

F'x

7:28 PM

@Szabolcs bye

Sjoerd C. de Vries

@Szabolcs bye

@Fx Question closed now. Didn't have to do anything myself, but added a (hopefully) positive message

F'x

@SjoerdCdeVries great, thanks

I wondering, shouldn't the long comments discussion on mathematica.stackexchange.com/questions/3414/… be nuked?

Sjoerd C. de Vries

@Fx It's a long discussion indeed. But there's also some actual information there. Deletions there will make it hard to follow. I have to look at it somewhat better. The last month I have been deleting 5 times more comments than mr.wiz and I myself really hate to have to do all that. It goes against my nature.

F'x

@SjoerdCdeVries I know it's not trivial to remove it, as there is some information

but across SE sites, it's been widely experimented that comment discussions are detrimental on the long term

Sjoerd C. de Vries

@Fx How long have you been mod in F L&U?

F'x

7:42 PM

@SjoerdCdeVries since Sep '11

Sjoerd C. de Vries

Busy job?

F'x

no, spookily quiet, in fact :(

Sjoerd C. de Vries

Is it in beta?

F'x

I must say it's been somewhat of a failure for now, gaining a nice core of dedicated users, but not much growth after the initial period

it's still in beta, and having less traffic than Mathematica :)

Sjoerd C. de Vries

French is too easy ;)

NOT!!

F'x

7:44 PM

the choice was made in the beginning to try and avoid "learning" questions, really

and also, to try and keep as much as possible in French

in short, to be an expert site on French language, mostly in French, rather than an easy-entry learning site

I do support that choice, as I wouldn't have gotten involved in a "ask your beginners' questions here", but it created a narrow path for us to travel

and attracting French experts on a site that has an English interface and not much love for non-ASCII character sets is hard :)

Sjoerd C. de Vries

I would expect a SE site to attract non-native speakers

F'x

@SjoerdCdeVries non-native is fine, and we have good non-native users

Sjoerd C. de Vries

Typing french on a US international keyboard isn't that hard, is it?

F'x

@SjoerdCdeVries tags don't support accented characters, search doesn't distinguish them, and so on…

Sjoerd C. de Vries

Aha, I see

F'x

7:48 PM

regarding non-native, the divide is more like we don't want beginner's questions

Sjoerd C. de Vries

est-ce le ou la?

F'x

@SjoerdCdeVries yes

among language SE sites, we were the only ones to go that way… but maybe that's not the only factor, because other languages (German, Japanese, Spanish and Chinese) aren't doing any better

Sjoerd C. de Vries

@Fx Did you publicize?

CHM

8:10 PM

@Fx will take a look at French.SE

It's a shame there's no support for éàùèïâ

F'x

@SjoerdCdeVries there's argument about that

initially, we were waiting for interface localization for publicizing

but I don't think we'll get this any time soon

CHM

But I find it a bit strange that a stack dedicated to French has an English name...

F'x

@CHM that wasn't a choice we were given by SE team :(

CHM

Quite sad.

F'x

plus the name has to be the same as the interface language

CHM

8:15 PM

But why accept foreign language stacks, then?

It seems a bit anglo(americano)-centric

F'x

8:36 PM

how do you extract RGB components from an RGBColor?

Sjoerd C. de Vries

@Fx huh?

F'x

@SjoerdCdeVries well, I got it: RGBColor[r,g,c][[1]] gives back r

Sjoerd C. de Vries

Part works for any expression

F'x

I am always amazed at that, yeah

CHM

I love Part[].

When I didn't know how to use XMLElement[], I navigated an XMLObject by doing obj[[1]][[2]][[1]][[1]][[2]] etc... lots of fun.

R.M

8:47 PM

@Fx or List@@color :)

F'x

@RM f-ck, I'll never get used to @@ and @@@

R.M

:)

F'x

@RM and I mean, "f-ck" as in "thanks"

R.M

@Fx This might help you with that — documents.wolfram.com/flash

2

F'x

@RM that's fun

CHM

8:52 PM

@acl yeah, but maybe not so much outside of university. My uncle's studied computer science (30 years ago, technical college) and didn't know him.

F'x

9:48 PM

@RM about the @@@ comment, I thought of it and then realized that I every time I try to use it, I get it wrong, so I'd better take the safe route :)

thanks though

Verbeia

New graphs on meta, updated this morning! Traffic is definitely rising.

Verbeia

10:15 PM

@Fx thanks for checking that: I'm not really a PDF maven

F'x

@Verbeia well, I'm out of time right now, but anytime you see me in chat you can ask for PDF help

though I have to say your files look fine to me, on all accounts

actually, the "export" PDF has an out-of-bounds object in it

  -2147483648 -2147483648 m
  -2147483648 2147483647 l
  2147483647 2147483647 l
  2147483647 -2147483648 l
  W* n

these coordinates are weirdly large

I'll check with the PDF standard when I get more time

wait, actually, that must be it; -2147483648 is the smallest signed 32-bit integer (and 2147483647 is the largest positive one)

so, the PDF is syntaxically correct, but it includes a hugely out-of-bounds object

which makes it correct according to the standard, but still weird

now, I cannot say what in the Mathematica export code creates this overflow, but it is clearly there

Verbeia

@Fx Thanks! That must be what is causing the error. I wonder if it is something I can stop happening in pre-settable printing options.

F'x

10:33 PM

it looks like a rectangle, so maybe it's exporting a frame or something?

Verbeia

just a really dumb approach to a bounding box?

I'm at home now so I can't replicate what is going wrong (mac at home, pc at work)

F'x

it's a page box, outside the bounding box

I can actually see it in Adobe, now that I know what I'm looking for

hum, I can't find what the W* operator is in PDF :(

Verbeia

maybe that's the error

F'x

duh, it's a filled white rectangle with infinite area

that, like, a dump way of doing a white background :)

I'm writing an answer with all that information, then

Verbeia

I wonder if setting Background->None as an option to Export in a package would hide this error from users (i.e. my colleagues)

F'x

10:42 PM

I think it would

let me rephrase: hopefully, it would

but then that should be the default already :)

F'x

10:57 PM

OK, I believe that answer is the least Mathematica-related answer on the site so far :)

0

A: Printing exported PDF graphics fails

Short answer: I hope Export["foo.pdf", plot,Background->None] fixes it. Let's get there step by step. First, Acrobat X Pro on my Mac reports that both your PDF files are fine. They print fine, and pass all tests with flying colors. I uncompressed the PDF (thanks pdftk) and a diff on them ...

Verbeia

@Fx Thanks !! Unfortunately I can't double-check this until I'm back in the office. That won't be until the 16th, as I have a business trip next week. But a couple of other users with Windows Mma could replicate the bug, so hopefully we will have confirmation sooner.

F'x

@Verbeia well, I hope it works, cause it was quite an investigation :)

PDF is usually nice (except when it comes to fonts)

but this is highly viewer-specific

Verbeia

@Fx thanks so much. I would never have worked it out myself.

F'x

none of the viewers on my Mac (including Mac OS's builtin APIs) fail on it

Verbeia

Mathematica is a bit weird with PDF. Exporting plots from the Mac failed quite badly when printing from a PC, and the file sizes are huge.

F'x

11:03 PM

well, I realize now I should have waited an hour before posting my answer :)

I'm rep-capped today!

but anyway, good morning to you and good night to me!

Verbeia

thanks again! good night!

R.M

11:46 PM

Something interesting to try at home with a Mac and Mathematica at hand:

5

A: Why does the wireless disconnect when cooking?

This really has nothing to do with unibody or macs, but is rather due to physics. I'm guessing that you're cooking using a microwave oven or have it running nearby when you're using your laptop. The 802.11b WLANs operate in the 2.4GHz band. Unfortunately, microwave signals also fall in the same ...

You can potentially map out the weak spots and possibly even figure out an optimum location to place your router (which, by Murphy's law will be as far away as possible from the nearest power outlet)

acl

@RM assuming you own a microwave oven...

R.M

@acl No, I didn't mean for the microwave oven... just mapping your signal strength vs location in the house.

acl

hm yes good point you don't need a microwave to do this...

guess I need some sleep :)

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