Start/Stop a Vertical Line

I’m using an activity from Jennifer Vadnais and making modifications. The vertical line is set to move across the graph when you click the button. I would like it to do 1 of 2 things below.

  1. Stop the vertical line from moving by clicking the button again.
  2. Stop at the point I direct it to stop (when it crosses 2 points at once).

Below is the link to the activity.

Thanks for any help given!

There are soooo many ways to do this, I hate to limit it with an example, but here’s one way:

From your post I assume you mean that you want a line to move across the screen until either a student presses stop or it reaches a certain point. If you add a max value in when you create the line you should get that behavior. Desmos | Graphing Calculator

Side note: I would LOVE to see all of the different ways that contributors to this forum handle this interaction!

Jay, don’t stop! Keep giving us more examples!!! I want to see them ALL!!!

PS I never think to use mod, it doesn’t come natural for me yet!
Still need to dig in to this CL, but excited to see the example!
Thank you!

Jay,
When I take your activity and add the table from Kay’s it works fine.
BUT, when I take Kay’s activity and add your pieces, it doesn’t work.
I’m confused. I even tried deleting and adding it all back in.


I thought maybe it was because the table was in spot 1 instead of bottom. I’m completely stumped!

Jay, you give me way to much credit because I can’t take what you did, put it into my activity, and make it work. Your knowledge is far superior than mine on coding. I’m lost! lol Is there a way you can take my file and do what you did on my slide 2, where I have the circle? Below is the link. Thanks for your help!

I’m sure it’s something really small!! Sometime variables collide when we try to combine activities. I’ll take a look later today.

This one works!
On the other one: I still don’t know why it sometimes works and sometimes doesn’t (or where I was messing up).

NOTE: (1 reason it sometimes didn’t work) I did discover that the parameter t_ime MUST be set to “play” and not pause. (Why? IDK)

I took your example and then adjusted with a mod expression so that the line repeatedly moves along the same path from -10 to 10.

I changed slide 2 for you. I didn’t look at what Jay did. I added CL into the btn1 and what is now graph1. The line still jumps back to the start because the time resets to zero.

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Example with timeSincePress, nice! Keep em coming folks!

Thanks to all of you! I finished the activity! Great support!!!

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Thanks! I actually thought the capture sink was the most useful part, so that components don’t continue to change. I’ve found it useful for feedback as well.