Write a Matlab code that shows the differences in compression reinforcement in case of changes in tension reinforcement in an unconfined concrete section with dimensions b$=300$ mm$,$ h$=500$ mm$,$ with tensile reinforcement ratios $=2\%,1\mathrm{.}25\%$ and $0\mathrm{.}6\%$ and compression reinforcement ratios $=0\mathrm{.}5\%,1\mathrm{.}25\%,2\%$ and $5\%.$ Explain the ductility and other parameters according to the graphs of the differences in compression reinforcement in the change of tensile reinforcement.