Wolfram Mathematica

rm -rf

6:00 PM

They might've just not had the need to use a custom template in v9... (that, and not many people know/use it)

halirutan

@acl I believe not many people really use the template thing, but that's only a guess.

Szabolcs

I wonder how many beta testers they have.

acl

@halirutan I also think so (otherwise, someone would have noticed that it does not work!)

rm -rf

I'm glad we don't have screaming idiots on this site (or that we shut them down)

halirutan

@rm-rf Yes, even if you use it for you day to day work.. (1) how often do you write full usage code and (2) how often do you use this on your own functions?

acl

6:03 PM

@halirutan that sort of proves that nobody uses it! I do this for pretty much every function I write

halirutan

@acl Can I ask since what version do you use Mathematica?

Szabolcs

@NasserM.Abbasi It's a little deceiving to have that drop to zero in the very last data point of each plot, but trying not to look at that, the Mathematica group seems to have had the least decline. Probably all the others have moved to other communication channel much earlier.

acl

@halirutan funny that you ask:

halirutan

@acl Hmm, it's funny how different the users actually use the software.

Szabolcs

I tried 4.0 first, and it was a lot of fun, but didn't get the chance to get serious until about 5.2

acl

6:06 PM

@Szabolcs that was exactly the same for me, too

halirutan

I really use the doc very extensively but never got used to the template expansions.

On the other hand in Java, I really enjoy what my IDE is doing for me and I use all kind of expansion, suggestions, etc..

rm -rf

@halirutan I always write usage messages with templates for stuff I put in a package... things that are in a notebook (and thus, floating), I just have some notes in a text cell

Rojo

Something will have to be redesigned for template expansions

halirutan

@rm-rf But are you using the template expansion for your own functions?

Szabolcs

I used to use Ctrl-K all the time, but Ctrl-Shift-K almost never

rm -rf

6:08 PM

@halirutan Yes, of course. Why would I write a template other wise?

halirutan

For others

using your package.

;-)

Rojo

They could even be automatic wihtout requiring usage definitions, in which case everyone would use them

rm -rf

@halirutan I'm in academia... I don't write for "others" =)

Kārlis Baumanis

sorry for the stupid question, but how to draw Circle in the Plot?

Rojo

Now we aren't restricted to just one expansion per function

Graphics[Circle[]]

acl

6:09 PM

@rm-rf nor produce anything, as has been repeated a few times here :)

halirutan

@rm-rf I do.. I love to code stuff for colleagues.

Rojo

Plot[Sin[x], {x, 0, 10}, Epilog->Circle[]]

Kārlis Baumanis

@Rojo thanks, but than I don't see X and Y axes

rm -rf

@KārlisBaumanis add Axes -> True

Rojo

@KārlisBaumanis Hard to know exactl what you want

You could also plot and then manually draw a circle with the drawing tools

halirutan

6:11 PM

@acl That's not true.. but I didn't wanted to join this discussion.

rm -rf

@Rojo or print the plot and use a compass + pencil...

acl

@halirutan I'm joking of course (otherwise I'd be claiming I am producing nothing myself!)

Szabolcs

@Kārlis Plotting functions, such as Plot, also produce Graphics objects with primitives such as Line, Circle, etc. inside. Try to put your cursor in a cell containing a plot and press Ctrl-Shift-I

halirutan

@rm-rf And if you want you can use different settings for Pi.. we already have a solution for this :-P

rm -rf

:D

halirutan

6:12 PM

@acl Yes, I felt that joke. I was just jumping on your train.

rm -rf

@Szabolcs Ha! I never knew that... is there a way to go back to the formatted expression using shortcuts?

halirutan

Btw, does someone know where we lost J.M.? I miss him for several days now.

rm -rf

He said he was going to be away for a few weeks

halirutan

Ok

Arnoud Buzing

Quick update: We're testing a new build for Windows with a fix for the Blue Screen issue. So far it is checking out ok (we can reproduce the Blue Screen issue and observe that the new build addresses the issue).

3

Oleksandr R.

6:24 PM

@ArnoudBuzing bad luck on your part to hit this issue! Did you report it to Microsoft? Seems like it might be known but not sure if this is the same thing?

@ArnoudBuzing hmm, does this patch mitigate the issue at all?

Kārlis Baumanis

@rm-rf after 15 minutes I found how to add Axes :) thanks for all answers!

Arnoud Buzing

@OleksandrR. It seems unrelated (and I have this patch installed), but I will check this out.

Oleksandr R.

@ArnoudBuzing certainly it would not be good to find yet another font-related 0day in win32k.sys, but to all appearances, unless there are some mitigating circumstances, you've uncovered a serious bug in Windows...

PAGE_FAULT_IN_NONPAGED_AREA is... well, a pretty bad crash.

soandos

Anyone know when Mathematica 9 is going to be re-released for windows?

Szabolcs

6:54 PM

@rm-rf Yes. Cmd-Shift-I is Input Form, Cmd-Shift-N is Standard ("Normal"?) Form, Cmd-Shift-T is Traditional Form. The latter two format Graphics as actual rendered graphics by default.

So just press Cmd-Shift-N. But I don't know how to do this for part of a cell only.

Arnoud Buzing

@soandos Our goal is to have this back up by the end of Monday.

soandos

@ArnoudBuzing if you don't mind me asking, what happened?

Arnoud Buzing

@soandos The Mathematica 9 installer fails to completely update previously installed versions of the Mathematica fonts. Our current reproducible case is to install V7, run it, then install V8, run it, reboot machine, start V8 again, make sure certain fonts are displayed, keep V8 open, install V9, reboot, start V9 and display certain fonts again.

soandos

@ArnoudBuzing thanks. Is there a website/page where updates will be posted?

Arnoud Buzing

@soandos The fix is to more rigorously remove any old fonts from previous installations, in a matter very similar to what is described here: support.wolfram.com/kb/11160

soandos

7:06 PM

But to rebuild the installers will take until Monday?

Arnoud Buzing

@soandos The user portal will have the replaced download and a new checksum.

soandos

@ArnoudBuzing perfect, thank you

Arnoud Buzing

@soandos The installers were rebuild last night and we're currently testing them.

soandos

@ArnoudBuzing, very nice turnaround

rm -rf

@Szabolcs Thanks. Would've been nice to have Cmd-Shift-F for FullForm, which is what I need more than the others. Nevertheless, good to know

Arnoud Buzing

7:24 PM

@soandos Thanks. Being able to communicate directly with users in this chat has been very useful.

Kārlis Baumanis

7:48 PM

is there a way to calculate trilateration with Mathematica?

Oleksandr R.

2

Q: Using triangulation

I have been presented with 3 known points and the power densities at those points. I need to use those points to find the location of the actual antenna which is generating the signals. Power Density is calculated through $PD=(power by antenna)/4*Pi*R^2$ and the inverse law also applies, $PD=\...

Kārlis Baumanis

@OleksandrR. thank you! I was hoping for something much easier.. this is way too complicated for guy who saw Mathematica for first time today :)

soandos

8:12 PM

@KārlisBaumanis basically it sets up the system of 3 equations and solves it, the same way you would do by hand

Kārlis Baumanis

@soandos the problem is that I don't know jet how to do it by hand

rm -rf

@KārlisBaumanis You might want to ask those questions at Mathematics then...

soandos

or physics.stackexchange.com

Kārlis Baumanis

@soandos there is good manual here en.wikipedia.org/wiki/Trilateration and good explanation here stackoverflow.com/questions/9747227/2d-trilateration I won't get anything better

soandos

@KārlisBaumanis so where is the problem?

Kārlis Baumanis

8:16 PM

@soandos imagine person who hears of vectors for first time and you will understand :)

soandos

Don't think of it in terms of vectors. Just think of it as a set of equations that have to be satisfied

(and vectors are not necessary I don't think)

Kārlis Baumanis

I think I would be useful for me to understand this example:
dist[x0_, x1_] := (x0 - x1).(x0 - x1);
power[x0_, x1_] := c/dist[x0, x1];
findAnt[l : {{_, _} ..}] :=
Solve[And @@ (power[{x0, y0}, #[[2]]] == #[[1]] & /@ l), {x0, y0,
c}];

l = {{1/3, {1, 0}}, {1/15, {0, 3}}, {3, {0, 0}}};
sol = findAnt[l];

Graphics[{PointSize[.05], Blue, Point[l[[All, 2]]], Red,
Point[{x0, y0} /. sol], Green,
Dashed, {Circle[{x0, y0} /. sol[[1]],
EuclideanDistance[{x0, y0} /. sol[[1]], #]],
Circle[{x0, y0} /. sol[[2]],

soandos

That involves quite a bit of complex syntax (for someone that does not know it already)

Kārlis Baumanis

@soandos yeah.. this is only 2D trilateration example I found

Kārlis Baumanis

8:33 PM

It is strange that I can't do Undo after I have evaluated cells

rm -rf

8:44 PM

@KārlisBaumanis Welcome to Mathematica =)

2

acl

8:57 PM

@KārlisBaumanis it is, yes :)

but at least the documentation is not dishonest: reverses the previous action, if possible

rm -rf

9:15 PM

@acl For ridiculous definitions of "action"...

Sjoerd C. de Vries

The option "FlowTable" in FindMaximumFlow doesn't seem to work

FindMaximumFlow[Graph[{"s", 1, 2, 3, 4, 5, 6, "t"},
{{{1, 2}, {1, 3}, {1, 4}, {2, 5}, {3, 6}, {4, 7}, {5,
8}, {6, 8}, {7, 8}, {4, 6}, {3, 5}}, Null},
{EdgeStyle -> {Arrowheads[0.06]}, GraphLayout ->
{"MultipartiteLayout", "VertexPartition" -> {1, 3, 3,
1}}, VertexShapeFunction -> {"Name"}}], "s", "t",
"FlowTable"]

Kārlis Baumanis

9:35 PM

.can I convert this to decimal numbers is.gd/dQgM22 ?

Oleksandr R.

@KārlisBaumanis no, absolutely not. Mathematica only works in base 29.

@KārlisBaumanis just joking. Here: reference.wolfram.com/mathematica/ref/N.html?q=N&lang=en

Kārlis Baumanis

@OleksandrR. tnx!

r1 = 8
r2 = 11
r3 = 8

In[183]:= x = (r1^2 - r2^2 + d^2)/2*d

Out[183]= 1/2 Sqrt[797] (797 + r1^2 - r2^2)

can you tell me why I see r1 and r2 in output?

instead of 8 and 11

I found a solution - I had to evaluate these first variables

Mike Honeychurch

10:51 PM

Given we've accumulated a bug listing here has anyone with 9 had a chance to see if any of these known bugs have been fixed (...if so maybe make an annotation?)

Transcript for