Bug / Corrupt File Needs Repair

Dave Yrueta shared this problem 1 year ago
Not a Problem

Hi All --

The following relates to this Geogebra activity: https://www.geogebra.org/ca...


The list named "l1" seems to exist, but its definition does not appear under the category of List objects in the expression bar. If you type "l1" into one of the expression boxes, you'll see what I mean. If I try redefining "l1" by setting it equal to another value (eg, "l1=7") the entire file crashes. Further, my function f(x, y)=xy is no longer viewable in 3D perspective. It seems the file is corrupt. Can it be fixed?

Edit: Since the "l1" list was a sequence based on evaluating a function f(x, y) on a list of points, the problem seems to go away if I delete the def of f(x, y) and then redefine it. Still, it's very buggy behavior.

Thanks!

Comments (3)

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Managed to fix the file, but only through lots of copying, pasting and renaming of variables. Here's the revised version for comparison: https://www.geogebra.org/ca...

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l1 is doing l * 1


The list is called L_{1}

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Hi Michael -

Yes, you're right: I managed to fix it by deleting the definition for f(x, y), which seemed to clear the file of it's definition of l1. I then redefined f(x, y) and set L_{1} to the old definition of l1. That put things right. Thanks for taking a look.

My next step for this project is to create a sequence of rectangular prisms to show the complete approximation of the volume under f(x, y). I'm pretty sure I know how to write the command to generate the sequence, but I'm concerned about flooding the display with labels of the prism edges. Is there a way to automatically suppress labels for a dynamically generated sequence of prisms? If you like, I can post this question to the board in general.

Thanks!

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