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Numerical Solution to a System of Differential Equations...



Can someone please help me solve this problem?

I have been trying (unsuccessfully) to numerically solve a system of
differential equations of the form y'=M.y, where y', M and y are all
matrices. I also specify an initial value matrix Init which will be
assigned to y0, the initial value vector.

Now, I try to solve using NDSolve:

In[4]:= NDSolve[ {MapThread[Equal,{y', M.y}],
MapThread[Equal,{y0,Init}]}, 
        y, {t,0,10}]

and obtain an output which looks like this:

Out[4]={y1[t]\[Rule]InterpolatingFunction[{{0.`,10.`}},"<>"][t],
        y2[t]\[Rule]InterpolatingFunction[{{0.`,10.`}},"<>"][t],
        y3[t]\[Rule]InterpolatingFunction[{{0.`,10.`}},"<>"][t]}}

(y1, y2, y3 are elements in the y vector.)

But when I try to look at the result for a given value of the dependent
variable t (say 5):

In[5]:= y3[5] /. %

all I get is

Out[5]= y3[5]

Thanks,
Ragavan,
University of Virginia




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