Hi,

I have a small problem. I want to findout area under a curve. I got the plot from solving a partial differential equation. I want to find out area under the curve with out using interpolation. Are there any methods to find this.

here i enclose the method i have done.

Es := 0.117108e12:

Ef := 0.78125e11:

l := 0.150e-6:

s := 0.500000e-3:

f := 0.5898334197e-6:

o := 0.9e-5:

d := 0.10e-17:

cb := 0.1e7/(19.9):

c := l*f/(d*cb):

PDE := diff(u(x, t), t)-(diff(u(x, t), x, x)) = 0:

with(plots):

with(plottools):

ys := -0.4245333333e-1:

IBC1 := {u(x, 0) = 0, (D[1](u))(0, t) = 0, (D[1](u))(1, t) = c}:

S1 := pdsolve(PDE, IBC1, numeric, time = t, timestep = 0.1e-2);

p2 := S1:-plot(t = .2525);

p3 := getdata(p2);

p3[3]:

co:=CurveFitting[PolynomialInterpolation](p3[3], x):

Area := int(co, x = x[1] .. x[2]):

So this is the procedure i used to find out, but can there be any other procedure to findout area directly from hte solution of PDE.

Thanks.