I need to do numerical computation by fourth order Runge Kutta Algorithm(adsbygoogle = window.adsbygoogle || []).push({});

in fortran. But I stuck in programming because the differential

equation contains imaginary part.

Take for e.g. the set of diff.equation are

x'=(i)y *exp(iwt) ;where i is imaginary no. and w is constant!

y'=(i)x*exp(iwt)

I tried to define complex function f and g as

f=(0,y *exp(iwt))

g=(0,x *exp(iwt))

and i defined x and y as real (because the argument of the complex

no.has to be real,right?/otherwise it doesn't accept)

But after every iteration,the x and y becomes real as

x=x0+some linear combination of the function f(which is complex)//and

real +complex gives complex no. and hence shows error!!!

So i unable to proceed further! So how should I proceed?

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# Differential equation in fortran

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