plotting - Iterator variable not blocked in ParametricPlot

Bug introduced in 10.0 and fixed in 10.3

It appears that perhaps the iterator variable r is not Block-ed in the ParametricPlot code below. This does not happen with other Plot* commands nor with Table. The plot is produced successfully, however.

r = {0., 0.5, 1.};
ParametricPlot[r {Cos[t], Sin[t]}, {r, 0, 1}, {t, 0, 2 Pi}]

Thread::tdlen: Objects of unequal length in {0.,0.5,1.} {Cos[t],Sin[t]} cannot be combined. >>

Am I doing something wrong, or is it a bug?

This happens in V10.0.2 and V10.1 (Mac OSX). It does not happen in V9. I came across this in my answer to How to make a ArrayPlot/MatrixPlot in polar coordinates?.

Answer

I assume it is a bug based on the following findings:

In v9.0.1 it does not happen.

Adding Evaluated -> False does not fix it. Strangely Evaluated -> True does fix it.

As you mention, other plotting functions, such as ParametricPlot3D, do not have this problem, regardless of the Evaluated setting.

This is not an answer, just some arguments on why I think it is a bug.

Comments

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