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I looked this up in the forums but there didn't seem to be a response.

I have the following equation:

##i\sum\limits_{n = 1}^N {{\sigma _n}} \left[ {\int\limits_{{\zeta _{n - 1}}}^\infty {\phi \left( \zeta \right)d\zeta - \int\limits_{{\zeta _{n}}}^\infty {\phi \left( \zeta \right)d\zeta } } } \right]##

where φ represents two cases:

Vertical Case:

##{\phi _V}\left( \zeta \right) = \frac{{4\zeta }}{{{{\left( {4{\zeta ^2} + 1} \right)}^{3/2}}}}##

And horizontal case:

##{\phi _H}\left( \zeta \right) =2 - \frac{{4\zeta }}{{{{\left( {4{\zeta ^2} + 1} \right)}^{1/2}}}}##

and ζ = z/r.

I am trying to express these integrals in summation form, but have never attempted discrete calculus. I apologize if the question is not complete, but I can try and provide more details as the post proceeds.

I am trying to learn.

Thanks!

VV5

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# How to discretize an integral

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