Simulation study in R

Here I am in a simulation study where I want to find different values
of x and y such that f(x,y)=c (some known constant) w.r.t. x, y >0,
y<=x and x<=c1 (another known constant). Can anyone please tell me how
to do it efficiently in R. One way I thought that I will draw
different random numbers from uniform dist according to that
constraints and pick those which satisfy f(x,y)=c. However it is not I
think computationally efficient. Can anyone here suggest me any other
efficient approach?

You have not specified the distributions proper for X and Y. Using a 
uniform distribution is only appropriate when it meets requirements.

One obvious approach is to sample one of the variables, say X, and 
then solve your equation for Y. If you're going to draw a lot of 
samples, it would pay to develop y = g(x) first.

But you need to know how to sample X in the first place. Is its 
distribution uniform, or something else?

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Robert A. LaBudde, PhD, PAS, Dpl. ACAFS  e-mail: ral at lcfltd.com
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