Negative numbers problem

Help with Snap!
1

Just by playing I put the number table to start with a negative number. Everything seemed to work fine but try to locate the number -1 by clicking on the squares. What could be the problem?

2

I have almost finished the numerical table, I have put all the options that I will need in class (with children of 6-7 years), but I can not understand the problem of -1. Instead of -1, -3 appears. All other negative numbers are going well, only the problem appears in -1. What could be the reason?

Now, to test the negative numbers you have to click on the question button and put for example -10 (so that the table starts counting from that number).

3

I haven't worked out in detail where the -3 comes from, but the underlying problem is that you can't use numbers as the names of costumes, because that SWITCH TO COSTUME block also takes costume numbers (i.e., position in the costume list) as input. The usual solution is to create a costume name with JOIN (X) (NUM) where X is a literal letter X (or anything else) and NUM is the variable containing the number.

4

You can use costume index this way
tablanum2 script pic

5

Thank you very much, I will keep in mind that using the SWITCH TO COSTUME...or by name or by number, but not a mix. But it is strange that if I use these blocks separately and I change the NUM variable by hand (-5, -4, -3, -2, -1...), it works fine and does not show -3 instead of -1.

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6

Thanks, it works, but I don't know why:sweat_smile:
And...it breaks the other options and doesn't show the numbers (only turtles appear).