@bill93?ÿ
This is not meant for occupation, it was meant to take the field located centerline shots and create an alignment for the designers to have a starting point to create the new road.
Here's an Excel spreadsheet that solves the problem using Newton's method. Whereas a tightly-written program is a scalpel, Excel is more of a meat ax when set to such a task. What would be loops in a program are just multiple rows of calculations in Excel. But nowadays memory is cheap and processors are fast, so why put a premium on elegance?
Note that the spreadsheet attacks only the first problem posed, the bottom row "duplicates" the OP's numbers for both of the problems he posted. I haven't looked at the second one, but it will probably yield to similar analysis.
Excel computes to 15 significant digits, so the precision of the final answer is limited by that. On the other hand, change is minimal as the iteration continues.?ÿ
Plug in other numbers for E and L and see how it works for you.
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