## Saturday, July 20, 2019

### Learning Computation Layer in Desmos: Day 2

Re-read my own notes from day 1, and I feel pretty ok with it. Still reading the Desmos CL documentation.

Sources:

So there's naming a component, which is different from script. You can name a component and not have any script associated with it, but not the other way.

"We can read things off all of its sources." I don't know what that means. (see day 4 for answer)

On screen 5, in the input, I entered 4^2, and this is what happened:

So 4^2 is being both converted into proper math notation AND evaluated. In GeoGebra, this happens in object boxes. To display 4^2 properly you use latex, and to display the value of 4^2 you type exactly that into an object box. Anyway.

The script was in the gearbox for the note. I just realized that I'm not sure where to put the script. Would it have made sense for the script to go anywhere else than under the note? Anyway this part of it defines the content sink with the : and the quotation marks enclose the string to be displayed. Not sure what the \${} is about. The script looks like:

content: "
You entered: \${l}
which evaluates to: \${v}"

Earlier in the script the variables v and l are defined:
v = exp5.numericValue
l = exp5.latex

and both those variables belong to exp5, which is the name of the input. So does this mean the exp5 is the source here? I typed 4^2 into the input and it got injected into the note AND the input. Soooooo the input is the source and the sink here?

Moving on, but not feeling steady.

Functions:

So the = is used to define a source (or a variable) whereas the : is used to define a sink? This script

latex = exp6.latex

uses exp6 as a source. I don't know why the word latex is at the beginning, but I think the one that's after the dot is there to define the type of data it is. Also, I don't know why we're seeing false and true suddenly.

Am I getting confused because I'm assuming I should already understand this but it will in fact be explained later?

Day 2 not going so well. I think it's time I looked at Jay Chow's site.