Re: fill in harberger triangle

*To*: mathgroup at smc.vnet.net*Subject*: [mg115755] Re: fill in harberger triangle*From*: r_poetic <radford.schantz at mms.gov>*Date*: Thu, 20 Jan 2011 06:27:33 -0500 (EST)*References*: <igrqfp$qqp$1@smc.vnet.net>

On Jan 15, 4:47 am, Bob Hanlon <hanl... at cox.net> wrote: > With[{a = .1, e = 1.4}, > Show[ > Plot[a*p^e, {p, 20, 120}], > RegionPlot[20 < q < a*p^e && p < 100, > {p, 0, 120}, {q, 0, 80}], > Axes -> False, > Frame -> True, > FrameLabel -> {"P", "Q"}]] > > Bob Hanlon > > ---- r_poetic <radford.scha... at mms.gov> wrote: > > ============= > Hello, > while the Filling option for Plot is great, how can I use it (or > another feature of Mathematica 8) to fill in only the area between a > curve and a vertical line and a horizontal line? For instance, > between (1) the function Q= A * P ^ E, where A and E are given > constants, (2) a horizontal line e.g. P = 100, and (3) a vertical > line, e.g. Q = 20. The fill is only inside the triangle-like area. > This would be the "harberger triangle" showing consumer surplus in > economics. > > Thanks! Thanks for all responses, I am finding that RegionPlot is a convenient way to fill triangles and other odd shapes created from market curves and reference lines. As for what is horizontal or vertical, note that economists are necessarily confused about that, since we persist in plotting the causal variable on the vertical axis! RS