Designing Games with Game Maker - YoYo Games

max(val1,val2,val3,...) Returns the maximum of the values. The
function can have up to 16 arguments. They must either be all real or all
strings.
mean(val1,val2,val3,...) Returns the average of the values. The
function can have up to 16 arguments. They must all be real values.
median(val1,val2,val3,...) Returns the median of the values, that is,
the middle value. (When the number of arguments is even, the smaller of the
two middle values is returned.) The function can have up to 16 arguments.
They must all be real values.
point_distance(x1,y1,x2,y2) Returns the distance between point
(x1,y1) and point (x2,y2).
point_direction(x1,y1,x2,y2) Returns the direction from point (x1,y1)
toward point (x2,y2) in degrees.
lengthdir_x(len,dir) Returns the horizontal x-component of the vector
determined by the indicated length and direction.
lengthdir_y(len,dir) Returns the vertical y-component of the vector
determined by the indicated length and direction.
is_real(x) Returns whether x is a real value (as opposed to a string).
is_string(x) Returns whether x is a string (as opposed to a real value).
String handling functions
The following functions deal with characters and string.
chr(val) Returns a string containing the character with asci code val.
ord(str) Returns the asci code of the first character in str.
real(str) Turns str into a real number. str can contain a minus sign, a
decimal dot and even an exponential part.
string(val) Turns the real value into a string using a standard format (no
decimal places when it is an integer, and two decimal places otherwise).
string_format(val,tot,dec) Turns val into a string using your own
format: tot indicates the total number of places and dec indicates the number
of decimal places.
string_length(str) Returns the number of characters in the string.
string_pos(substr,str) Returns the position of substr in str (0=no
occurrence).