Wolfram Mathematica

Sjoerd C. de Vries

6:37 PM

@Verbeia who made this ad?

acl

7:14 PM

@Heike your routine works just fine if I order my points

acl

7:54 PM

@All, compare these

Pick[{{{0, 0}, {1, 1}}, {{1, 1}, {5, 5}}}, N@{Sqrt[2], 4 Sqrt[2]},
  x_ /; x < 1] // Trace
Pick[{{{0, 0}, {1, 1}}, {{1, 1}, {5, 5}}}, {Sqrt[2], 4 Sqrt[2]},
  x_ /; x < 1] // Trace

how can I predct this behaviour from the docs?

Sjoerd C. de Vries

@j.m @mr.wizard The guy whose question we deleted on his own request (about accessing a website using MMA) has probably appeared again under a different name. I deleted his question (about javascript) because a link in this question linked to what looked like a porn site.

Verbeia

@SjoerdCdeVries It's the collaboratively created one from here: wxffles' basic design, Szabolcs' idea for the ad, my suggestion for colour scheme and slogan.

@SjoerdCdeVries Could that just have been a dummy site name? The thing about that question for me was that it all it did was create a dialog box to get a URL, and you can do that direct in Mma without Javascript.

Sjoerd C. de Vries

@verbeia Well, the author even used the link in the short Markdown format [...](...) in a conversation with me in the comment, suggesting to click on it. The link was alive and AFAI could see behind my NoScript barrier it involved porn. I requested he removed the link and edited the question but got no response, so I deleted. Question was low quality anyway.

Heike

8:09 PM

@acl Pick doesn't restrict itself to lists nor to the first level. If you look at {Sqrt[2], 4 Sqrt[2]} // FullForm you get List[Power[2,Rational[1,2]],Times[4,Power[2,Rational[1,2]]]], so the elements that satisfy x_ /; x< 1 are 1/2 (== Rational[1, 2]) at positions {1,2} and {2, 2, 2} of {Sqrt[2], 4 Sqrt[2]}

acl

8:19 PM

@Heike yes I understand what is happening, but how could I have predicted from the docs that in the second case it would try to match not just the top level of the two expressions, even though {{{0, 0}, {1, 1}}, {{1, 1}, {5, 5}}} and {Sqrt[2], 4 Sqrt[2]} have different depths?

R.M

@SjoerdCdeVries you could just delete that comment and change the URL to example.com in the question...

acl

@Heike I mean, look

Heike

@acl I looks like Pick tries to match as deep as it can go, i.e. as long as the structure of the two expressions still matches, or until the first match. In this case the structures of the two expressions match up to the level 2 so that's how far it will go.

Sjoerd C. de Vries

@MrWizard This is the code with my additions removed.

acl

The docs say "The "selector" list has to have the same length and structure as the data". Well, here they are not, unless you do things like interpret Rational[1,2] as one node

Sjoerd C. de Vries

8:24 PM

DynamicModule[{pts, range, gr, drag, pts0},
pts = RandomReal[1, {7, 2}];
range = {Span[1, 4], Span[5, 7]};
gr = {{Red, Polygon[Dynamic[pts[[range[[1]]]]]]}, {Blue,
Polygon[Dynamic[pts[[range[[2]]]]]]}};
drag = 0;
Panel[
LocatorPane[
Dynamic[pts],
EventHandler[
Graphics[
EventHandler[
gr[[#]],
{
"MouseDown" :> (drag = #;
pts0 = # - MousePosition["Graphics"] & /@ pts[[range[[#]]]])
}
] & /@ {1, 2},
PlotRange -> {{0, 2}, {0, 2}}
],
{
"MouseDragged" :>
If[drag > 0,
pts[[range[[drag]]]] = # + MousePosition["Graphics"] & /@ pts0],

Mr.Wizard

@SjoerdCdeVries With that code I am able to drag both polygons with left-click-and-drag. (Or right, for that matter.)

acl

@Heike that seems to be the case here yes. But I was wondering if there was anywhere in the documentation where I could find a complete description

Mr.Wizard

Let me go try your original code again with a fresh kernel just to be sure.

Sjoerd C. de Vries

@MrWizard Well, must be one of those undocumented v7-v8 differences then.

Heike

@acl The documentation on Pick seems to be a bit minimal.

acl

8:27 PM

@Heike I was hoping there was a tutorial somewhere with more detail

Sjoerd C. de Vries

@heike Could you test my modification of your code?

Mr.Wizard

@SjoerdCdeVries I suppose so. Confirmed on a fresh kernel with -noinit: left fails but right works.

Sjoerd C. de Vries

4

A: LocatorPane and multiple EventHandlers, PassEventsDown option

The following code does what you want. It requires that you press shift to move a locator that is being overlapped by a polygon, instead of moving that polygon. DynamicModule[{pts, range, gr, drag, pts0}, pts = RandomReal[1, {7, 2}]; range = {Span[1, 4], Span[5, 7]}; gr = {{Red, Polygon[Dyna...

Heike

@SjoerdCdeVries Your code seems to work fine on my system.

Sjoerd C. de Vries

@Heike your on v8 too, right?

Heike

8:30 PM

@SjoerdCdeVries Yes, 8.0.4 for OSX

Sjoerd C. de Vries

@heike We should ask Brett if he could arrange a courtesy copy of v8 for mr.wiz

@Rm The comment he posted was: "the url does not seem to end in anything that's the problem: look at it: [link]( "http://www.xxxxx.com/framesetperpc.asp?lang="+lang+"&ref="+strCheckRef;")" He clearly intended me to click on it.

Heike

@SjoerdCdeVries Or of v9

Sjoerd C. de Vries

@Heike Yeah! And include us in the party as well ;-)

Mr.Wizard

@SjoerdCdeVries Thanks, but I'm just being stubborn about waiting for v9.

@SjoerdCdeVries what question was this? I need to keep track of such things.

Heike

@SjoerdCdeVries I think anyone with >3000 rep deserves a copy of v9

6

Sjoerd C. de Vries

8:35 PM

Try to estimate the number of hours we spend here; bill that with a consultancy fee of, say, $100. One copy should be a cheap way to man a help desk.

3

Mr.Wizard

@Heike Good luck with that! Maybe if you make it 20K+ someone might consider it....

R.M

@MrWizard you guys should talk to the community team/chaos re: possible promotions during v9's launch... See diablo3acts.com, skyrimvsmw3.com and thenewipadishere.com for some previous contests. Also this:

Blog - Stack Exchange: More Notes on Contest Format

Lauren Gundrum on April 20, 2012

A few months ago, I outlined a contest formula called “Hot Topics,” which has become a staple in CHAOS’s site-promotion efforts. For those who missed that post, Hot Topics initially worked like this:

Pick a topic of the week, and enter everyone who asks a question related to that topic into a random drawing to win a prize. The number of entries a person gets is equal to the number of questions they ask about the topic of the week.

We now have a few variations on this contest format.

Variations on the Hot Topic Format …

I guess technically, all that's needed is a meta post with little more details than wishful thinking

This was a start... perhaps needs to be taken up again when v9's release date is known for sure

Sjoerd C. de Vries

@rm So, Chaos (which I gather is the SE promotion team) could fund a few copies?

Heike

@RM I'm not sure what this would do to the community spirit.

Things could get pretty competitive.

Sjoerd C. de Vries

@Heike That may be a concern indeed

R.M

8:39 PM

@Heike I agree with that... we need to come up with our own format and present it to them. One that does not turn us all into nasty piranhas

I participated in the apple contest (and won an ipod) and it was very nasty... voting nearly shut down unless it was a true diamond of an answer. On the last day, people started strategically downvoting others just to get ahead in the race

Mr.Wizard

@RM That sounds like nothing I want to bring to Mathematica.SE.

R.M

@MrWizard hence "we need to come up with our own format and present it to them."... I would hate for that to be brought here too.

Mr.Wizard

Yes I understand, I just had to add my two bits.

R.M

Oh, the main reason that apple's was bad was because it wasn't exactly a draw of lots... they made it so that the top X at the end of the contest won stuff, which meant that you could win if someone else was lower than you. Gaming's contests generally are very popular, and they have a randomness factor in determining the winner(s)

Heike

@RM Sounds like the british education system.

R.M

8:48 PM

ha!

Heike

Maybe we could get someone high up at WRI to be judge.

Sjoerd C. de Vries

@RM I undeleted the question. You may have a look at it, but I think this is a not a well-thought-out question

Heike

@SjoerdCdeVries Do you think the dubious link was an accident?

Sjoerd C. de Vries

@Heike He claims that was the case, but I don't see why he would put in in a clickable format in a comment then.

Heike

@SjoerdCdeVries He has also put a ;) after it which doesn't help his case, although I don't know if that was there before he changed the link.

Sjoerd C. de Vries

9:03 PM

@heike I changed the link. I asked him to do it himself, but he didn't. The ;) was there.

The question doesn't make sense to me at all. It boils down to having MMA launch a Javascript script and have that collect data from another site and get that data back in MMA. But where should the script run? Javascript is usually browser only, so you should have a webserver hosting this code.

belisarius

9:28 PM

Anyone knows if there is any video format which could be used to Import both audio and video into Mma?

belisarius

9:45 PM

?

Heike

@belisarius I don't think there is. Maybe you could save the soundtrack of the video as a separate sound file.

belisarius

10:37 PM

@Heike Thanks! That s what I am doing, but I am experiencing some synch problems when I save both image and sound after some manipulation.

Nothing that I can not solve by other means, I mean

That is why I don't post it as a Q

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