Please write here the piece of code which computes the functions F₁,...,F_n which make up the ode's right hand side F(x,y). This must have the mathematical structure
F_i = F_i(x,y(1),...,y(n)).
You must obey the FORTRAN conventions.
Input values are n, x, y, output value is f. The left hand side of this must be f(i) = with i ranging from 1 to n. 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). No other variables can be used.
c******** dummy for the case of using predefined c******** y''+y-1=0, y(0)=0, y'(pi)=-1 => y(x)=-cos(x)+sin(x)+1 f(1)=y(2) f(2)=-y(1)+1.d0

Please write here the piece of code which computes the functions R which make up the boundary conditions:
The input variables are the vectors ya and yb and the result is a vector r, all of dimension n. You must formulate these such that the condition r = 0 corresponds to R(ya,yb) = 0. You must obey the FORTRAN conventions.
The problem variable n can be used. You might use here local 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).
c**** boundary conditions y(0)=0 y'(pi)=-1 y=y_1, y'=y_2 r(1)=ya(1) r(2)=yb(2)+1.d0 c****** these are linear inhomogeneous conditions

Please specify here the interval bounds
a =
b =

Please specify whether you know the exact solution or not:

	The exact solution is known. Write the piece of code for comtuing it below. There is only one input variable x. The result must be named y The rules for coding this piece of program given above apply. y(1)=-dcos(x)+dsin(x)+1.d0 y(2)=dcos(x)+dsin(x)
	The exact solution is not known

Here you decide whether to generate the initial guess for the solution internally or to specify it directly:

	generate it internally This requires the input of the code for ytrue! Specify the amount of perturbation here: perturb =
	Direct input of yinit This requires minit × n values!

Warning!!! - This may take some time.

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

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