Help with aggregate, lists and histograms

I’m using aggregate to collect pendulum timing data from a class. Here are some questions I have:

  1. How can display the data so that students can copy/paste the data for later use? Apparently, you can’t pull a desmos table or list INTO the paste buffer…
  2. When I show two histograms of overlapping distributions on the same graph, the areas of overlap are hard to read. I want students to see both histograms distinctly and simultaneously. Is there a way to show the two “stacked” histograms- perhaps on one graph by shifting one vertically or reflecting it across the x-axis? Or perhaps in two resized graphing windows?

Here’s the activity: Unit 0 Prototype • Activity Builder by Desmos

Thanks for any help you can provide,
David Abbott

You can add the max value of one list to the other for its histogram, effectively shifting right by the max value. Here’s a sample. I added an additional unit to have a separation between the histograms. I also removed the x-axis labels in order to manually insert a set for each histogram.

Daniel,

What you propose shifts the graph horizontally- not vertically. I’d like students to see two overlapping distributions simultaneously to visually compare central tendency and spread.

David

I found a solution to problem #1 above. It’s not very elegant, but it works. It uses “elementAt” to list the first twenty elements on the list: Here’s the CL from the Note:

A=aggregate(GetTTop.numericValue)
content: "Here’s a list of the first twenty data points from the class. All times are in seconds:

{A.elementAt(1)}, {A.elementAt(2)}, {A.elementAt(3)}, {A.elementAt(4)}, {A.elementAt(5)}, {A.elementAt(6)}, {A.elementAt(7)}, {A.elementAt(8)}, {A.elementAt(9)}, {A.elementAt(10)}, {A.elementAt(11)}, {A.elementAt(12)}, {A.elementAt(13)}, {A.elementAt(14)}, {A.elementAt(15)}, {A.elementAt(16)}, {A.elementAt(17)}, {A.elementAt(18)}, {A.elementAt(19)}, {A.elementAt(20)}"

Along the way, I noticed that there might be an (undocumented) sink for Note called exportNumberList. Does anyone know what exportNumberList does and/or have an example to share?

Oops! Something happened to my CL code in the cut/paste process. The correct code is in the updated version of Unit 0 Prototype (see link above).

You could display a histogram for list 1 and a histogram for the combined lists. There doesn’t seem to be a way to mess with the overlay or opacity, which I think would make it more like what you’re looking for.

You can get frequency counts like this, and then make your own histograms using something like in this thread:

Thanks, Daniel. I think I will build my own “reflected” histogram using the tools you’ve pointed to. Nice to learn about join, sort and unique operators. Hadn’t seen those yet…

David