@halirutan Hopefully you've seen the thawed room.

@0x4A4D What is that?

@halirutan I thawed the chat room for your plug-in.

It was frozen, but now thawed.

@0x4A4D Ah, I see it's open again.

Thanks

@WolframBlog "...most Mathematica 1.0 code will still run unchanged today." - I love how you weaseled yourself out with the word "most", Stephen. :P

hi there - does anybody know whether one is allowed to specify a function as such?

Function[{param1,param2,{param3a,param3b,param3c}}]

or must I specify it as Function[{param1,param2,listparam1}] and then within my code take specify that {param3a,param3b,param3c}=listparam1?

I like my parameters being highlighted in green for readability :)

@VincentTjeng No, only symbols or list of symbols are allowed.

@VincentTjeng What you can do is something along this

okay then

f = Function[{a, b, l},
  Block[{c, d},
   {c, d} = l;
   a + b + c + d
   ]
  ]

What's the prupose of the Block[]?

ah... I see

that's very nice :)

@VincentTjeng The purpose of Block is to localize c and d so that you don't overwrite/use global variables.

yep. I was trying to figure out whether it would have any impact on my code and I think it should work just fine. Now i'm wondering what the difference in use between Block[] and Module[] are though - would you have time to explain?

@VincentTjeng Very popular question. Lucky for us we have a site where those get answered: mathematica.stackexchange.com/questions/559/…

i should really do a search next time first. thank you!

No problem

@halirutan would you by any chance happen to know whether having a Manipulate[] called within a function will cause a drop in performance? I'm Manipulating a Plot of InterpolatingFunctions generated by NDSolve[], am trying to figure out whether the problem is general or specific to what I'm plotting.

by calling within a function, I mean that I write it as Function[{a,b,c}, Manipulate[...]]

instead of a=a0, b=b0, c=c0 then Manipulate[]

@VincentTjeng This shouldn't have influence in the way you described it.

okay. let me work out what the real problem is and post it as a question here if necessary. it seems to be rendering the plot ten times slower though, I waas wondering whether it was due to some value being calculated repeatedly.

@VincentTjeng This is very likely but I don't think it's related to Function

@VincentTjeng I have a system of 120 ODE's that are fairly large of the form Manipulate[Plot[Evaluate[NDSolve...]]] and haven't seen much decrease in performance when adjusting sliders... at least no more so than one would expect with 120+ fairly large equations.

Ah, not sure about the performance impact of Maniuplate within another function though.

where positionFunction is simply a small custom function i wrote to get the position of each of my particles at timeValue with n as the total number of particles

so basically I'm plotting the solution to all the ODEs at a given time, then manipulating the time.

anyone here know some logic

@VincentTjeng I'm not sure, but if you do figure out how to increase performance on that front, do share. I'll do the same. I can't see a way around having to re-evaluate the NDSolve command, though...

yep, will do!

@Ethan I would offer to help, but I'm not sure if I could do much ... (seeing your level of mathematics)

@Ethan I, too, am fresh out of logic. Shipments are blockaded from the East and West, not sure when we'll get more... ^.^

@VincentTjeng You don't happen to know a way to only have the Plot display one or two (or any select few) of the many solutions to larger, coupled ODE systems, do you?

@Ghersic - what exactly do you mean?

when I solve an ODE, i normally get a list of interpolating functions

I call my coupled equations z1, z2, z3, ..., z120 for the 120 equations (where zn' are given in terms of other zn)

ok.

(are they solvable analytically?)

So my setup is Manipulate[Plot[Evaluate[z1[t], ..., z120[t] /. NDSolve[{z1'= ..., ... z120' = ...}, {z1, ..., z120}, +(other specifications for NDSolve)] +(Manipulatable parameters)]

@Ghersic in terms of mathematical logic can you give me a definition of 'type'

The book I am reading defines it as a "representative of inscriptions that look the same and utterances that sound the same"

oh no, they are highly non-linear (but only first-order)... that is actually a separate projects of mine, to linearize them to approximate the system.

@Ethan One second, let me look into that.

i find this definition kind of vague, could you elaborate possibly with a few examples, I would greatly appreciate it

so how do the solutions to the system differ? AFAIK, one set of starting parameters would only lead to one (numerical) solution - or am I mistaken there?

@Ethan - sorry to be asking this, but have you tried the Math chat? This is the chat for Mathematica.

yes lol

that is normally where i am

okay haha

@VincentTjeng Are you sure you need a pure function? You can make definitions like f[a_, b_, {c_, d_, e_}] := which is similar to what you wanted

@rm-rf In fact, I don't - but I've used pure functions all the time since I started programming in MMA, i'm not sure exactly how := behaves.

@VincentTjeng If you have slow to compute functions, use ControlActive to do the computation only when the slider is let go and display something else meaningful when dragged. Also, plotting functions are plotted twice — first with PerformanceGoal -> "Speed" and then with "Quality". To avoid this, set it to quality in your plotting command

@rm-rf I shall try that

lol

@Ethan It sounds like in type theory, fundamental operations (addition, subtraction, etc.) are each their own distinct "type" of argumentation. However, I'm not too familiar with symbolic logic. Sorry.

ahh, thanks anyway

@Ghersic ye I was looking for more of the second one, the definition on wikipedia uses model theory and some other stuff

@Ghersic do you study mathematics?

I've graduated but studied physics and mathematics in university (just at the undergraduate level) with an admittedly disproportionate effort towards the applied mathematics / physics side. Employment has, of course, bolstered my concern for the applied side.

You study biology?

@Ethan I wish I had more of a knack for theoretical math.

@Ghersic ahh I just study what ever seems interesting or makes me happy

@Ethan Yes, as of late anyways ;). I suppose you could call it physical virology. Heavy emphasis on mathematical modeling, which is very on the applied side.

@Ghersic so you study microbiology?

That's good... you just have to do that until you get good enough at it someone throws money your way for it. haha

Aye. It's a trip, lemme tell you. Makes me wish I had taken at least a few upper level chemistry and biology classes rather than almost exclusively physics, haha.

Yes, I have found some topics in biology interesting some stuff about Abiogenisis in particular, but I suppose interest in things like this is natural in any field in which the topic confronts fundamental questions, i would assume these attract lots of inexperienced/curious people, and or cranks.

I am trying to stay grounded with one field though, I guess id rather be sort of experienced in several fields rather then being a 'jack of all trades'

Yeah, specializing has greater chances netting you larger pay anyways... as fun as multi-disciplinarity is.

That's why I'm not too embarrassed to have been nodding off a bit during the more biochemical / less mathematical portions of group lab meetings...

@Ghersic Mind if I ask where your from lol

Bloomington, IN in the US... just a college town of a liberal arts / science research university. You?

California, I am still in high school

you watch any television?

I'd like to visit the west coast sometime. I'm only 22, so not that old comparatively.

Usually just shows I've stuck with for awhile, Game of Thrones, Dexter, etc. that friends hooked me on long ago. Other than that, I try to tell myself I don't watch much TV.

I waste time in other, equally frivolous ways.

lol I usually watch the coltbert report, the dailyshow or archer/american dad other then that I don't usually watch alot of tv, mostly comedy if I do

*colbert

something like this works... but seems unnaturally troublesome

@VincentTjeng Hi Vincent. I think those NumberForm thing (and his friends) are actually what the standard Plot used. It may look troublesome, I think that's why they hide all those things behind a simple Plot.

Hmm.. It's so annoying images hosted on i.stack.imgur.com are occasionally blocked by THE Firewall..

Ah, Friday evening. The start of a time to work on what your boss hasn't given you time to work on during the week for fear of failure... mmm, research as a non-Ph.D.

Haha, just kidding of course. Hope everyone's Friday (insert time period) is going well.

Looking to the right, my God man, a NASA rover prepared bagel would be the most delicious thing since... robot sliced bread.

@halirutan Congratulations on the request to write for them! That is awesome. Alright, I'm done spamming everyone with my well wishes.

@Ghersic Thanks. The editor likes my article and I will add some final changes tonight or tomorrow.

@halirutan nice