Possible bug : curve undefined

cooooldog shared this question 5 years ago
Answered

In order to create the following animated GIF:


44f4d42552300faf00e1e0fdd5fb8933


I uses the following GGB:


https://ggbm.at/569353


When you open the GGB, and enable animation for slider f, you will find both curves h and i become "undefined".


By copying

    r=If[5 > f > 0, 2^(4(5 - f) / 5) + 1, If[f ≥ 5, 2, ? ]]


    but, i don't anderstand your algorithm...

    choose a value for ?


    I try to modifie ? to k ( slider)

    and it's ok (?)

    https://ggbm.at/569357

photo
1

First, when I initially created the curve via

    Curve[r cos(v) - r + 2 + cos(v) (1 + sin(5r (π / r + v))), r sin(v) + sin(v) (1 + sin(5r (π / r + v))), v, -2π / r, 2π / r]

without closing and re-openning the GGB, then it worked successfully in obtaining the GIF;

So there should be no problem in either the slider or the algorithm;


second, I tried to edit the objective properties of the curve, by adding "f>=0" to "condition to show object" in Advanced tab, it seems the problem disappears: even I close and reopen the GGB, there is no "curve undefined" problem any more. Or the "condition to show object" in Advanced tab would disappear when curve becomes undefined!


https://ggbm.at/569367


So still I think this might be a bug.


Hi,


it doesn't work because r is not defined for all values of f :

r=If[5 > f > 0, 2^(4(5 - f) / 5) + 1, If[f ≥ 5, 2, ? ]]


but, i don't anderstand your algorithm...

choose a value for ?


I try to modifie ? to k ( slider)

and it's ok (?)

photo
1

Try to see the attached GGB which I modified the "Condition to show object" options of the two parametric curves, under the Advanced Tab of Object Propertes.


https://ggbm.at/569369


Nothing else changed

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