@b3m2a1 Message about zero or negative element quality usually means that you have wrong ordering of element nodes or that some node positions coincide.

@Pinti Hmm I see. Any reason you know of that something generated from a plain ToElementMesh call with its internal default constructor would make that happen?

@b3m2a1 I am not sure if I understand your question? If you specify wrong order for element incidents then ToElementMesh will complain (with message) but still generate ElementMesh object. But the latter then doesn't work as basis for interpolation.

Hi everyone! Quick question for you. Is there a function which given a list will return an association/2d array of the number of distinct items and how many items they appear in the list? Something like: clojuredocs.org/clojure.core/frequencies

Nevermind! Got it! It's Tally.

@JeelShah or Counts

Awesome! Thanks!

@Kuba You would know the answer to this: why does the following not work?

Manipulate[ExampleData[spec], {spec, ExampleData["TestImage"]}]

This works:

Manipulate[
 ExampleData[spec], {spec, ExampleData["TestImage"],
  ControlType -> PopupMenu}]

Why is the control type not auto-detected in the first case? It's clear that it has to do with the nested list, but I don't know which specific other syntax it conflicts with

@Szabolcs probably because of heurystics they use for Manipulate

You can start with PrintDefinitions@Manipulate`Dump`processParameterForTypesetting

I can't focus on this right now :)

Does anyone know of a way to accept the free-form input interpretation using only the keyboard? Or how can I interact with the free-form input result in general (using the keyboard)? I often use it to enter quantities, and it would be nice to have a workflow along the lines of "CTRL+= -> enter e.g. 5m -> accept" without having to move my hand to the mouse

@Szabolcs I think it's interpreted as the last form of Slider[] in the docs: Slider[Dynamic[step], {ExampleData["TestImage"]}], in which the second argument should be of the form {{{e, w}..}}, where the e are expressions and the w are relative widths. Manipulate apparently does not parse the list to see if the w are valid numeric values.

@LukasLang On a mac, shift-backarrow, cmd-return (i.e. select, evaluate in place). I don't know another way.

Of course, that would evaluate the expression, so it's not exactly what you're looking for.

@MichaelE2 Yes, that's it!

@MichaelE2 Thanks, that seems to work perfectly for my use case!

Is there an image processing function that will take an image and a marker (a binary image), and will extend marker points to cover parts of image which are within a given gray-value range?

Like MorphologicalBinarize, but using a marker instead of an upper threshold

@halirutan Perhaps you'd know this if it existed in Mma ^

It's also similar to FillingTransform, which does take a maker. But I only want to fill up to a given height.

Hey folks, just a reminder that Stephen will be livestreaming today at 2:30 CST. This will be a follow-up on the paclet system framework.

@LukasLang I have packed your changes into a new release and it should soon be published in the Chrome store.

@C.E. I fixed up the submission form a bit so that now it can just format the request for you to copy-and-paste: paclets.github.io/PacletServer/pages/…

But without you needing to give any passwords

@JKlug I'm not a crazy person in thinking it's ~2:30 CST, right?

SW about @halirutan

@b3m2a1Sorry I didn't see your message. I left the room once the stream was scheduled to begin. But you're correct. Any time that I post for a livestream, you can be certain that it's CST

@Szabolcs I hope I did understand correctly what you want. Here is an idea:

szBinarize[img_?ImageQ /; ImageColorSpace[img] === "Grayscale",  marker_?BinaryImageQ, dpixelValue_?NumericQ] /; ImageDimensions[img] === ImageDimensions[marker] := Module[
  {vals, result},
  vals = Values@
    ComponentMeasurements[{img,
      MorphologicalComponents[marker]}, {"Mask", "Mean"}];
  result = Function[{mask, mean},
     SelectComponents[
      Binarize[img, {-dpixelValue, dpixelValue} + mean],
      Total[Flatten[#Mask*mask]] > 0.001 &]
     ] @@@ vals;
  HighlightImage[
   img,

And then you can do something like

img = ColorConvert[ExampleData[{"TestImage", "Lena"}], "Grayscale"];
mask = Image[ConstantArray[0.0, Reverse@ImageDimensions[img]], "Bit"];
mask = ReplaceImageValue[mask, {{275, 245}, {330, 60}} -> 1]

szBinarize[img, mask, 0.1]

Hacky, but I assume you get the idea.

@b3m2a1 "You can include here any other info you want that'll build to the server. Do this as a list of Name: Value pairs." What does this mean?

or nvm, I guess I know what it means.

@b3m2a1 When I click "Generate Request" it says "Password field must be filled out"

@C.E. Ah good check I forgot to turn off that alert for that button. You can always put in trash but I'll change the JS to not check for that.