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). They 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 d. The left hand side of this must be d(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. d(1)=-4.d0*y(1)+y(1)*y(2)*x+3.d0*y(2) d(2)=1.d0*y(1)-2.d0*y(2)-x*y(1)*y(2)+0.1d0

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 w, all of dimension n. You must formulate these such that the condition w = 0 corresponds to R(ya,yb) = 0. You must obey the FORTRAN conventions.
The problem variables n, m 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).
w(1)=ya(1)-ya(2)-1.d0 w(2)=3.d0*yb(1)-yb(2)-2.d0 c****** these are linear inhomogeneous conditions

Select two components of y for plotting:
index1=index2=1 is allowed

index1 =		Important index1 from 1,...,n !
index2 =		Important: index2 from 1,...,n !

Here you must choose the initial guesses and some
parameters for BVPSOL

The number of grid points : m = The grid points : (must be in increasing order, a is the first and b the last one!) 0.0, 0.3, 0.6, 0.9, 1.2, 1.5 The initial guesses for the solution on this grid (the example is for n=2 and m=6): 0,1, 1,0.5, 1.5,0.2, 1.5,-0.2, 1,-0.5, 0,-1 The desired precision in solving the nonlinear system for the initial values si Must be in [1.0e-16,0.01]: tol = The maximal stepsize of the integrator (should be smaller than the minimum griddistance/5) Mustbe in [1.0e-16,1]: hmax = The maximal order the integrator should try (requires 2maxord/2 evaluations of F for each step) Mustbe in{2,4,...16}: maxord = The maximum number of Newton steps allowed, must be >=2 : itmax = The amount of output of the BVP solver (damped Newton solver) : info=-1 none, info=0 intermediate values, info =1 very detailed info =

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