PlaysDice

@CarlLange I've followed the field a bit. Most good SDR software seems to be python-based and as you know, now, WL ...

@ChrisK. Yup. SW pretty much kept answers limited to his stated AMA topic:his infrastructure and the related blog post.

@Kuba Thanks. I had wondered if the $ was a by-product of the Demonstration-intake/publish process. A quick check of another Demonstration had no suffix$. The original Demo had local variables w/o the $ too.

Is anyone else ticked that, as far as I can tell (emails to WR) Mathematica Annual Subscription now does NOT include updates/upgrades during that year - you need to add a Personal License or Service Pack to get those updates? I have no idea if even bug fixes are included. For sure, WR can set whatever terms they want for their product..but this change just seems out of step with what most people expect - or until recently received - under an subscription license. Is it just me?

In beta: Wolfram University. Video tutorials, a 'scratchpad' and supporting text alongside. Impressive see example

@William. Works for me m11, Ubuntu 14.04 and m10.3 same system

@Searke sorry, just saw your answer too. Argh Volume@Ball[]

@YungHummmma At the risk of being misunderstood, the answer is "balls". Mathematica calls the 3D (solid) a Ball, and not a Sphere. For example Volume@Ball[r] gets volume of unit object.

@ShutaoTANG @Shu It may or may not be what you asked but this article discusses matrix inversion johndcook.com/blog/2010/01/19/dont-invert-that-matrix

Anyone else tried Wolfram Programming Lab or Development Platform? I really want to like them but I find they break too often. Case in point- just tried WPL and it crashed as I tried to edit one of their examples - as the guide text suggests. I then tried to use the on-page feedback box but it has hung trying to send!

@J.M Well don't bottle it up on my account

@J.M. now you're going all "group theory" on my dodecahedron ;)

@MichaelHale @J.M appreciated. I baulked at even trying to plot them but now you've kindly parsed them, I can see clearer how they work.

@J.M. huh! N@, its is. Thanks!

......

(sample output)..{{-Sqrt[1 + 2/Sqrt[5]], 0, Root[1 - 20 #1^2 + 80 #1^4 &, 3]},

Wolfram support assures me the "slots' are correct. If thats the case, how do I turn the coordinate list into a plotable set?

PolyhedronData for a (unit) Cube gives nice, clean VertexCoordinates. But for a (unit) Dodecahedron (and many more) Mathematica returns coordinates with Slots.

@IstvánZachar thanks, @Pickett too. GeneralUtilities` requires v10.1. When I upgrade I look forward to exploring!

@IstvánZachar fair enough. btw- what does PrintDefinitions@RunProcess do?

@IstvánZachar Run["date > output.dat"] works for me on v10.0.2 on Ubuntu. The function returns '0' which means 'successful completion'.

@William if you are on Linux, the command line 'tail' can select n lines from the end. It can be accessed via Mathematica using the ReadList[... command. A quick google suggests there is a [Windows equivalent] (stackoverflow.com/questions/187587/…)

@halirutan ... I took another read of the Docs and I can see that the first variable in Quantity is a (numeric, absolute) magnitude and my passing Quantity in there messed it up. So, maybe not unexpected behavior, but just not what I was er, expecting.

@halirutan thanks for checking. Odd behavior (Quantity[Quantity... ] ) but your work around is appreciated! Even appreciated ^2 ! :)

gives 24 h (squared). Is it just me ?

On v 10.0.2 Quantity[Quantity[1, "Days"], "Hours"]

@blochwave. I am (v10.0.2, 14.04 LTS). Its running stable, no probs.

@kirma. I went and made a very crude parser that takes a limited set of Mathematica input (multivariate equations and variable definitions) and outputs a .z3 format text file than can be handed to z3 on the command line. It aint pretty (and I need to hand edit some things in the .z3 file) but it works and now saves time.

@kirma Do you know of a way to link Mathematica with the Z3 running on the same machine (e.g. bindings)? After your post I tried Z3 via rise4fun.com. In the blink of an eye Z3 solved a problem Mathematica couldn't handle.

@Karsten. Thanks. uT is smaller, for sure. As far as I can tell, perp isnt listed as a named character. +1 for the random monkeys!

hah! (random typing later).... its [esc] perp [esc]

Can anyone guide me if M has the special symbol 'eet' (basically an upside down T)? I cant see it in the documentation

@chuy thanks! I also like the use of outside brackets to turn Sequence into List.

Is there a way to feed back the result of a Reduce into the original equation? (toy example...) whereas Solve[x^2==16] gives rules { x->4, x->-4 }(easy to feed back into the formula), Reduce[x^2==16] gives x=4||x=-4 - I cannot see how to feed this back.

I think its often said, but worth repeating...Mathematica.StackExchange is a great site full of helpful people. Thanks to all !

Its not just a job search tool. You can find consultants, check out competitors, track who the HR-bod just got LinkedIn with to shadow possible job competitors. (+You're welcome).

I think it would be (better to create). It takes time to gather, build and edit a profile, and perhaps get some written recommendations posted (not 'skills' endorsement clicks).

@Kuba. It depends. Its interesting to track colleagues' colleagues..... 'competitive intelligence'. Its becoming spammy with the ''endorsements' (of your skills) by people who have only a passing acquaintance with you. The web-based portal allows you to tailor a sentence or two in introductions. But the mobile version shoots a generic, plain msg, making you look lazy. Useful..? Maybe, sometimes, although not a critical tool for me. But imho, its main game in town.

@halirutan. Done.

I've been working on the SAX approach but am stuck after standardizing and grouping datavalues and turning them into Strings. SAX then clusters them by string dis/similarity. The only built-in Mathematica String dis/similarity I can find is based on substitutions. I think the SAX approach requires that the difference between ABC and FBC isnt MMA's "1" (1 substitution) but "4" (letters different). Is there an alternate suggestion?

Can someone outline a good approach to group datasets, based on their plots having 'plots' of the same shape ? Extreme examples would be datasets that plot like: horizontal line, a diagonal line (uptrend), diagonal (downtrend) and a square wave.

@MichaelHale. Thank you! That's what I wanted.

for clarity, an ideal output would be { r[g[b]] , r[b[g]] }

@halirutan on your recent graph answer if we get a 'branch' with, say, relations r [ g[b] , b[g] ] how can I get (using a generic approach) each sub-branch r[g[b]] and r[b[g]] ? I tried various Maps and Applys

@MichaelHale Sounds like a bad case of WolfREM (TM)

@Szabolcs. I haven't tested but I wonder if the burden of ParallelTable is causing your laptop to emerge from some form of power saving and increase clocking to the CPU.

anyone interested in helping me on a quick Graph AdjacencyMatrix Q?

@user14717 In your answer you mention you solve equations for a living. I'm curious.. can you provide some general details about the type of problems you solve?