ODE: initial value problem - Gragg-Bulirsch-Stoer
user defined problem

Please specify the dimension of the vector y here
n =   Important: 1 <= n <= 10!

Please write here the piece of code which computes the functions f1,...,fn
which make up the right hand side of the ode y' = f(t,y), f = (f1,...,fn)T. They must have the structure fi = fi(t,y(1),...,y(n)). You must obey the
FORTRAN conventions.
You might use here variables i,j,k (e.g. for loops or counting), the logicals bool1, bool2 , bool3, a vector of 100 components v(.) , the variables h1,h2,h3,h4 (e.g. for intermediate calculations) which all are initialized with zero resp. false and the constants pi, e, sqrt2 (with their mathematical meaning).

Specify the integration interval:
t0 =
tend =

Specify the initial values for y
This is a list of n numbers, separated by blank or comma.

Select two components of y for plotting: index1=index2=1 is allowed
index1 = Important index1 from 1,...,n !
index2 = Important: index2 from 1,...,n !

please specify the relative precision you want to obtain
tolrel =
please specify a typical value for ''small'' function values to be replaced by this parameter smally in the relative error criterion:
smally=

Please select the maximum allowed stepsize hmax:
hmax = Important: 0 < hmax < (tend-t0)/2 !

Please specify the maximal order allowed:
maxorder=
Important: 2 <= maxorder <= 16 and even

Please specify the number of subintervals of equal length, which must be processed separately:
1 <= num <= 100. 1 means there are no fixed intermediate grid points (recommended).

Warning!!! - This may take some time.

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

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22.03.2011