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Here are the functions i've made using mathematical functions in a plc.
The most are very easy, but mostly effective to make a program more readable. The variable type that is used can mostly easy be converted to another type. You have to change the In and Outputs of the FC's and change the math function to the type used in the new function.
Not all functions are tested to the bone!

download awl source (incl. functions.)

Symbol table:

Limit (int)	FC 1040	FC 1040	Limit (int)
Y = a.X+b (int)	FC 1041	FC 1041	Linear formal: Y = a . X + b
X = (Y-b)/a (int)	FC 1042	FC 1042	Linear formal: X = (Y - b)/ a (invert of FC1040)
Y = a.X^2+b.X+c (int)	FC 1043	FC 1043	formal: Y = a.X^2 + b.X + c

limit: FC 1040: Limits a value and write the min. or max. value is not in range.

Input:	EN	Enable function
	Min	Lower limit of the value
	Max	Upper limit of the value
In-/Output:	Value	If value is smaller then min then the value is set equal to min If value is bigger then max then the value is set equal to max
Output:	ENO	If value is changed ENO is high.

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Y=ax+b: FC 1041: Linear function Y = a.x + b

Input:	EN	Enable function
	a, b & X	The variables of the function
Output:	Y	Result of Y = a.x + b (linear formal)
	ENO	If there was an error in the formal ENO is high.

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X=(Y-b)/a: FC 1041: inverted linear function X=(Y-b)/a

Input:	EN	Enable function
	a, b & Y	The variables of the function
Output:	X	Result of X = (Y - b)/ a (opposite of the linear function described above.
	ENO	If there was an error in the formal ENO is high.

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2nd degree function: FC 1043: 2 end degree function

Input:	EN	Enable function
	a,b,c & X	The variables of the function
Output:	Y	Result of Y = a ·X² + b ·X + c
	ENO	If there was an error in the formal ENO is high.

The opposite formal:

X =	-b ±√(b² - 4 ·a ·(c-Y)) 2 ·a

It's possible, but I have not made it yet.
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