Difference method for a BVP - user defined

In the following three fields you will specify the computation of f(x,y,y'), g1(y(a),y'(a)), g2(y(b),y'(b))
These pieces of code have a common structure: for your computation 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.
remember the special role of the first 6 columns in these pieces of code!
Here follows the code for f. The input variable names are x, y, ys, with the meaning ys=y'(x). The output must be named yss

Here follows the code for g1. The input variable names are ya, yas. The result must be named g1. You must formulate the boundary condition as g1(ya,yas)=0. Due to a curious error in JAKEF you must write a von Neumann condition by adding and finally subtracting ya, for example the condition
y'(a) = 1
must be written as
g1= ya + (yas-1.d0) -ya .
The same applies for g2!


And here the code for g2. The input variable names are yb,ybs. The result must be named g2. You must code this as g2(yb,ybs)=0

Here you may choose whether to use fictitious points or not
no appears as version 1 in the plots
yes
appears as version 2 in the plots

Please specify the number of grid points here: this must be in the range {3,1000}
N =

Here you decide whether to use some default values or to specify these explicitly:
Use the defaults
itmax =
  eps =
specify whether to print a solution table or not:
no
yes

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 definig it in the following area. There is only one input variable x. The result must be named yex
The rules for coding this piece of program given above apply.
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

Warning!!! - This may take some time.

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

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02.06.2016