Adaptive quadrature using Simpson's rule

Please choose an integrand:
f(x) = 1.0/((x-0.3)**2+0.001)+1.0/((x-0.9)**2+0.004)-6.0
f(x) = cos(40.d0*x*pi)**2
A function of your own:
Please type the evaluation program of your function here using FORTRAN rules. Your final statement must be
      fu= some expression you computed before or just here depending on x
You may use the constants pi, e(=exp(1)), sqrt2(=1.414...), the integer variables i,j,k, the logicals bool1,bool2,bool3 and the double precision variables sum,h1,h2,h3,h4,y(100),z(100),a(100,100) which are all intialized with zero resp. .false. . The routine has the parameters x (double, input) and fu (double out). never change x!. first is a local integer and set 0 before calling the function the first time. You may use this in order to initialize some local data and set it 1 afterwards to avoid multiple such initialization. Your settings of the local variables are preserved during program execution.

Please specify the interval of integration (a < b):
a = b =

We also need an upper bound for the stepsize:
hmax=

hmax <= (b-a)/10 is controlled internally.

Choose your desired precision (bound on the absolute error):
eps=
Important: 1.0e-10 <= eps <= 0.01

Click on "evaluate", in order to submit your input.

A message ''h reduced to hmin'' may be issued for a too small eps or if f is not smooth

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14.05.2015