If there are functions that you don't know how to perform in LiveStage, then you can email to Matthew Peterson.
If you have more functions and you would like to contribute, then you can email to Francis Gorgé

Trucs et infos: Numerical Recipes for LiveStage
A
ABS: ABSOLUTE VALUE. Built-in function. ABS(x)

ATAN: ARC-TANGENT, Inverse tangent.

ATAN(x) =
x-x*x*x/3 + x*x*x*x*x/5 - x*x*x*x*x*x*x/7 + x*x*x*x*x*x*x*x*x/9 - x*x*x*x*x*x*x*x*x*x*x/11

This is an approximation of the standard ARCTAN function and returns an angle in radians (See RAD2DEG). It is only valid for values of x between -1 and 1. If you want a "4 Quadrant ARCTAN function" (also called ARCTAN2),
please download the script.
C
CART2POL: Cartesian coordinates to polar coordinates.
Download function from:
http://www.mindinst.org/livestage/DistandDirection.hqx

CEIL: CEILING FUNCTION. For positive numbers: ceil(x) = (x + 0.9999) DIV 1
ex: ceil(5.2) = (5.2 + 0.9999) DIV 1 = 6

COS: Cosine Function. Download the script.
D
DIV: Integer division. Built-in function. a DIV b returns the integer number of times b can divide into a. ex:
5 DIV 2 = 2

DEG2RAD: Converts degrees into radians: DEG2RAD(x) = x*3.141593/180, or x/57.3
E
Exp: Exponential Function. Possible to do. If you need this function, please
email matthew@pinoko.berkeley.edu
F
Floor: Flooring function. For positive numbers, Floor(x) = x DIV 1. Same as Trunc(x).

ex: Floor(5.9) = 5.9 DIV 1 = 5
M
MAX: Maximum Function. MAX(a,b) = (a+b + ABS(a-b))/2
ex MAX(2,4.5) = (2+4.5 + ABS(2-4.5))/2 = 4.5

MIN: Minimum Function. MIN(a,b) = (a+b - ABS(a-b))/2
ex MAX(2,4.5) = (2+4.5 - ABS(2-4.5))/2 = 2I

MOD: would like to warn people that the MOD function in LiveStage 1 is not really a MOD function. It is actually a REM (Remainder) function.
What's the difference?
Well, x MOD y has the same sign as y while x REM y has the same sign as x.
This is a very important distinction.
a MOD b = ((a MOD b) + b) MOD b
0
Perspective: Download Spinner Script

PI: PI constant: PI = 3.141593 (approximate)

POLAR2CART: Converts polar coodinates to Cartesian coodinates.
Use x =r*COS(angle), y = r*SIN(angle)

Download script for COS and SIN functions.
R
REM: Remainder function. The built-in MOD function is actually a REM function in LS 1. See MOD.
builtin function in livestage PRO

ROUND: Round to nearest integer. ROUND(x) = ((ABS(x) + 0.5) DIV 1) *
(x/ABS(x))
If you know that x is positive, you can use ROUND(x) = (x + 0.5) DIV 1
If you know that x is negative, you can use ROUND(x) = (x - 0.5) DIV 1

WARNING: You must first check that x is not zero.

ex: ROUND(4.6) = ((ABS(4.6) + 0.5) DIV 1) * (4.6/ABS(4.6)) = 5
ex: ROUND(-4.6) = ((ABS(-4.6) + 0.5) DIV 1) * (-4.6/ABS(-4.6)) = -5

RAD2DEG: Convert from Radians to Degrees: RAD2DEG(x) = x*180/3.141593, or x*57.3
S
Sign, sgn: Returns the sign of the number(1 or -1). sgn(x) = x/ABS(x)
WARNING: You must first check that x is not zero.

ex: sign(-4) = -4/ABS(-4) = -1

SIN: Sine function: Download script.

SQRT: Square Root function. Download the script.

If you are using the squareroot function to calculate distance
( SQRT(a^2 +b^2) ) you might also want to look at the Angle and Distance Calculating script:
Download script.
T
TAN: Tangent Function. Download script.

TRUNC: Truncate decimal portion off, leaving only integer portion. TRUNC(x) = x DIV 1

ex: TRUNC(4.7) = 4.7 DIV 1 = 4