Tan Function Rounding Error

[thisandagain]

Expected Behavior

Tan of 90 returns infinite, NaN, or similar. Tan of 180 should give 0.

Actual Behavior

Because we're converting from degrees to radians, there is a rounding error. Such that you get to nearly 0, and large numbers, but not the exact number / result desired.

Steps to Reproduce

Input values into mather operation, set to tan, click.

Operating System and Browser

Ubuntu 16.04, chrome 56.0.2924.76

I am sure you're already working on this, just adding an issue so I can share our first play test findings / complaints.

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Moved from scratchfoundation/scratch-blocks#779
/cc @SillyInventor

[thisandagain]

A PR with associated unit test coverage (see "operators" test suite) would be most appreciated.

[SillyInventor]

Sure.