Hi Kyle,
First, I still don't understand. I do not know what your abbreviations stand for. I assume this is a Civil Engineering problem. I am a yacht designer, not a civil engineer, so I can tell you what GM, LCF, etc mean, but not "PVC sta", "grade in" "grade out" etc.
What it seems like to me is that you have two different spots in a road, each with a required slope of the road (2% and 3% here) and a certain distance apart, and elevation difference, and you are asked to draw a smooth curve of some sort between them. Is this true?
As far as programming goes, that is really not so hard---you just type in what you do "by hand" but in program mode, and you have most of it.
If you need to solve iteratively, then you can put an expression into a subroutine, use the Fn=label to set that routine, and then have your main program solve. Or, you can write one single routine and manually solve that routine for your unknown variable.
For your Equation, it would be, in ALG mode,
(be sure you are in ALG mode before you start typing in, or your "(" won't work)
LBL label
ALG
INPUT I
INPUT L
INPUT B
INPUT S
INPUT P
INPUT F
INPUT E
{and INPUT for any other variables I forgot--
be sure all of them are there}
RCL I
-
RCL L
/
2
*
etc
etc
/
100
)
y^x
2
)
-
RCL
E
ENTER
(put an RPN statement here if you prefer RPN command operation)
RTN
Note that I moved your "E=" to the other side as a minus E, so as to make the whole thing an expression.
To solve for your variable, you would go back to regular mode (RPN or ALG) and say FN=label, and then SOLVE _variable.
Alternatively, you could simply re-write your equation in either program mode, or in the equation list, and move the "E" across so as to make it all an expression, and solve for the variable you want to. If you do an equation in a program, be sure to decide whether to clear or set flag 10 to control automatic prompting--you won't need auto-prompting if you include INPUT statements in program mode. If you are in the equation list, the Solver will attempt to algebraicly find a direct solution first.
You can also use initial guesses by storing your lower guess in the variable, and your upper bound in the x-register (calculator line) and then solving.
You will find most of this in the manual (and the other stuff from Gene's recent post!).
Best regards,
Bill
Edited: 8 Sept 2004, 5:13 p.m.