I have set of inequalities in two dimension space which represent relation between $X$ and $Y$. Now I want a function whose input is $X$ and output is $Y$. In other words, I want $F$ such that $F(X)=Y$ satisfying given inequalities.
For example $$ X \le 0,~ Y\ge0,~ X\le63,~ Y\le15, ~X\ge4Y,~ X\le4Y+3$$
Now in above case if I input X, function should return Y. Hence, for example, in above case $F(0)=0$ and $F(4)=1$ and so on...
You can plot these function on WolframAlpha and see how it gives integer solutions. But I'm looking for a function which maps X to Y.
Is it possible to get such function?