@sblom I do have plans to resume my work on package manager, that I did some time ago. But I will have time to do that probably starting in July only. Some related work is here, and in a number of my gists. I may have occasional windows before July to kick-start this, though. If you are interested, I will keep you in the loop.

@LeonidShifrin Great! I've got a prototype package manager bootstrapper written, but I haven't put much thought into package format, and it looks like that's something that you've thought a lot about. :)

My work so far lives here: github.com/mathematica-packages/mpg

Any c-programmers listening atm? I'm playing with CCodeGenerate for the first time, making the code for the example cf = Compile[{{x}},x^2]. Found the libraries, figured out how to make the header file, so I can compile the c code. However, if I run the program it segfaults. The troublemaker is fun(wld, in, &out) with in and out cast as mreal and wld as WolframLibraryData.

I suspect I'm not handling/initializing the WolframLibraryData properly, but this is now over my head.

Nevermind, I read the manual.

@sblom I see you found the right person to talk to :).

@Murta Can one delete content of a Databin?

@or-anyone-else

@Kuba yes!

@Murta how? :) !

In the site.. datadrop.wolframcloud.com

ahh...

-.-

@Murta Thanks ;)

@kuba If you discover how to do it using code, I would like to know.

@Murta is this a known fack that DirectoryName on OSX can't recognize "Dir\File.nb" as a valid path and returns ""? It needs "\" before while it is not creating any with FilenameJoin...

@Murta Or not. Don't read this. I made a mistake.

Hey guys, I want to apply a function to a column in my matrix and I was seeing @VitaliyKaurov's answer in here (mathematica.stackexchange.com/questions/3069/…). However, doing something like list /. {list[[All, -1]] -> Log10@list[[All, -1]]} doesn't transform the column. What am I doing wrong?

Ahem, please disregard my question. I forgot to transpose it...........

@Sosi Keep in mind the very first line in this answer, I wouln'd use this method.

@Sosi for V9+

MapAt[Log, list, {All, -1}]

or if you want to modify existing list

MapAt!! I never remember it!

list[[All,-1]]=Log@list[[All,-1]]

@Kuba rsrs.. ok. I'll not :)

@WReach Thanks! That's very helpful.

@Kuba Ya, but I'd like to avoid doing the Log@list[[All,-1]] since then I'd have to prepend or join the rest of the list

@Sosi No you won't. Try

list[[All,-1]]=Log@list[[All,-1]];
list

oh duh...

I was thinking "why is he suggesting this? If I do Log@list[[All,-1]]; it only returns the last column! this doesnt make sense!"

now i feel stupid :3

@Sosi Don't! :)

either way, thanks @Kuba !

I'm not certain if the first and especially the third book on that blog post really fit nicely on the same row.

Why not "Special Integrals of Gradshteyn and Ryzhik ... for Dummies" ?

I think that unige.ch/~hairer/pictures/ode_I.gif and images.springer.com/sgw/books/medium/9783662099476.jpg are very complete :)

:)

Can someone help out in here? It seems a simple question but I don't know enough to help the OP mathematica.stackexchange.com/questions/80462/…

It's just a matter of keeping the arguments unevaluated if I'm correct?

@Sosi Yes, SetAttributes[deltaf, HoldAll]; seems to solve the problem

I dont want to take credit, so maybe you could post that as an answer or comment there? :)

as the the argument f1[A, x] is not evaluated.

@Sosi Please take the credit, first of all, it was your idea, I've merely did a check.

@IstvánZachar thanks. I commented there

On a side note, why does my username and links look different than the rest? they show up in lighter colors to me

@Sosi Perhaps you can work out that as a full answer (as it qualifies!), even edit the question title accordingly! It gives good rep for you.

See the differences there?

@IstvánZachar but but, YOU solved the problem!

@Sosi Perhaps you have already visited your profile, so the link indicates it with a faded color?

eh, it's the first time I see it this way

@Sosi Well, the previous comments clearly indicate, that you got it right!

I see my name and all those I've visited recently faded as well.

@halirutan Thank you. I will use it from now on.

@IstvánZachar ok ok, thank you for being so kind!

My pleasure, I assume those reps make more relative difference at your end than mine : )

ahahah ya! 24k holy cow!

Hi everyone, I'm plotting Tubes in Mathematica, and setting the VertexColors explicitly. However, for some reason the colors are wrong when rendered, Orange is appearing as Red!

I've tried the default Lighting and Ambient White light, but in both cases Orange appears Red...

It is not an issue if I set the color via Graphics3D, e.g. Graphics3D[{Orange, Tube[...]}]

Bird wing

Manipulate[
 Graphics[Line@
   FoldList[AngleVector, {0, 0},
    Accumulate@Table[Sin[x - t]/4, {x, 0, Pi/2, Pi/12}]],
  PlotRange -> 7], {t, 0, 30}]

@MichaelHale Nice :)

@Kuba Thanks. Actually I just saw AnglePath. Shorter version:

Manipulate[
 Graphics[Line@AnglePath@Table[Sin[x - t]/4, {x, 0, Pi/2, Pi/12}],
  PlotRange -> 7], {t, 0, 30}]

When I saw they added ReIm I was hoping there was a CosSin. I was disappointed, but then I saw AngleVector and now AnglePath.

@MichaelHale That's nice you are happy. I would be with bugfree front end :)

This is really bizarre

Yellow looks like yellow

Blend[{Orange, Yellow}, 0.9999999] looks like Red...

@Guillochon It looks like Yellow in 10.0.2 under Windows. What version are you running?

9

I'm doing some simple tests, can't easily reproduce it

Only showing up in a more complicated rendering

Oh, I think I see that you are using this in 3D graphics? Right. I hope you find a minimal example to post; I'd like to learn what is happening.

Yeah, 3D graphics. Trying to come up with a minimum example but I'm not quite sure what's going on

There's some other strange things going on too, I have a Blend in the VertexColors, but everything in the Blend is appearing as black

It could be a location of the lighting in the scene?

It might also be a delayed evaluation, ugh

@halirutan I read your comment but I don't really have a well reasoned opinion to share.

OK, I figured it out

It affects Tubes that are passed a BSplineCurve

The tube should be Orange, but appears Red.

Take away the BSpline and it looks correct.

@Mr.Wizard You mind giving that example a try?

BezierCurve does the same thing too

@Guillochon Sorry, it takes ~20 minutes for Chat pings to reach the person if he is not in the room.

@Mr.Wizard No problemo

That does indeed appear red. I'll see if I can find anything useful. Thanks for the example.

@Guillochon If you use VertexColors -> {Hue[0.166], Hue[0.167]} You get a rod that's green on one end and red on the other. It seems like some kind of "snapping" (quantization to nearest primitive color) is taking place.

@Mr.Wizard Yeah that's what it seems like to me too. Not sure there's any way around it.

Probably another bug :-/

Think I should make a post?

@Guillochon I think that is best; it both gets some measure of attention and lets others provide an alternative if they are aware of one.

@Mr.Wizard mathematica.stackexchange.com/questions/80530/…