What does this function do? 1

That's basically it. The bolded equal sign is the constraint, i.e., find an "H" such that the RHS expression is equal to "L" which is presumably defined above, along with q and a.

The assignment operation H:=find(H) assigns the found value that satisfies the constraint back into H for use below, but is not required otherwise, i.e., you could stop at "find(H) =" if you only what do see what the value is, and one could always copy the found value back into the guess value. The reason for forcing a guess value is that one might be looking at a constraint equation with multiple solutions, and the user might desire finding only one particular solution.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list

Thanks IRS... do you know what the function/equation does, and what the variables are?

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

Maybe something to do with a catenary:
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I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list

Thanks IR, good to get that cleared up. If I may also ask; do you have any idea what this monstrosity might be doing?

F is a function whose roots at H1 and H2 are to be found. Beyond that, the outer root call seems a bit unnecessary, since the two roots are linearly combined with delta; one would think that just requires some algebraic manipulation. The inner root functions seem to have more parentheses than necessary as well.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list

Thanks...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik