Can I use Stata to plot the graph of implicit function?

[Raymond Zhang]

Dear all,
I know that Stata can use twoway function to plot the graph of explicit function, such as

twoway function y=x

but my question is that how can I plot the graph of implicit function?such as sin(x)*cos(y)+exp(y)*log(x)=0?
Can Stata plot this kind of graph?Any help will be appreciated.

Best
Raymond

[Nick Cox]

I can’t visualize that from the equation alone, but twoway function is for single-valued functions. There are tricks: for example a circle or ellipse can be drawn as upper and lower parts. The most general method is to calculate (x, y) pairs that lie on the curve and join them smoothly. If a curve is closed the last pair should be a copy of the first.