Question: Integrating a function with Runge-Kutta (rkf45), trouble evaluating solution past initial point.

Hey there,

I've been struggling for a few days to integrate a function using rkf45.

For some context, I wish to numerically intergrate a function K * s_R (K,a,w) dK using runge kutta over a 2D grid of (a,w) values. Essentialy, performing the same sort of K-integral many different times for slightly different combinations of a and w. For one such (a,w) combination, the function looks something like this:

and rkf45 works just fine, and returns a numeric result. On the other hand, for a different combination of (a,w), the function looks like this:

and an attempt to perform rkf45 returns the following error: "cannot evaluate the solution past the initial point, problem may be complex, initially singular or improperly set up."

Here is a simplified version of my maple document for reference

I'm happy to clarify anything that may be confusing and any thoughts or suggestions would be greatly appreciated.

Thank you!

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