Is this a bug?

[ptc-5793265]

The image should be self-explanatory, but I am plotting a half circle in 3d space, extruded along the x-axis. Everything seems to be working except that the range that I set for y does not seem to work.

Now we play the ageless game: bug or user error?

[ptc-5793265]

Really looks like a bug - if I define "z" to be between -1 and 1, now the plot shows the half circle extruded along the y-axis instead of extruding it along the x-axis as I intend.

[AndyWesterman]

Prime will only return a single, positive, value for the square root function ; so your plot will only show 1 half.

to plot the other , the easy way is to define a second function as -sq root.

regards

Andy