Math & Science ⇒ multido | Endpoint Approximations under Curves

[mmdailey]

I'm trying to type up examples of right endpoint approximations of area under curves and I would like to be able to use multido to create the rectangles.

What I would love is for the code below to work. It is creating 6 rectangles using right endpoints for f(x) = 2x + 3 on the interval [0,3].

Code: Select all

\psset{xunit=.5cm, yunit=.5cm, algebraic=true, plotpoints=10000}
\begin{pspicture}(-10,-5)(5, 10)
\psgrid[subgriddiv=1,griddots=10,gridlabels=0pt, gridcolor=gray](0,0)(-10,-5)(5, 10)
\multido{\n=0+0.5}{6}{
        \psline(\n,0)(\n, 2*\n +3)
        \psline(\n, 2*\n+3)(\n+0.5, 2*\n +3) 
        \psline(\n+0.5, 0)
        }
\end{pspicture} 

Is there an easy way to do this? Thanks.