User-defined Function

Menu location: Data_Transforming and Deriving_User-defined Function.

This applies an algebraic expression to any selection of data. The workbook column(s) you select are given the variable names X1, X2 ... Xn in the order that they are selected from left to right across the workbook. You can then create a new column as a function of those selected. You do this by entering an algebraic expression that can use any of the functions, operators and constants below. For example X1/SQR(X2) would produce a column where each row entry was that of the first selected column divided by the square root of the corresponding row entry in the second selected column.

The same results can be achieved using intrinsic functions within a StatsDirect workbook. Large complex functions may be handled faster by the intrinsic workbook functions of StatsDirect.

Constants
PI	3.14159265358979323846 (p)
EE	2.71828182845904523536 (e)

Arithmetic Functions
ABS	absolute value
CLOG	common (base 10) logarithm
CEXP	anti log (base 10)
EXP	anti log (base e)
LOG	natural (base e, Naperian) logarithm
LOGIT	logit: log(p/[1-p]), p=proportion
ALOGIT	antilogit: exp(l)/[1+exp(l)], l=logit
SQR or SQRT	square root
!	factorial (maximum 170.569)
LOG!	log factorial
IZ	normal deviate for a p value
UZ	upper tail p for a normal deviate
LZ	lower tail p for a normal deviate
TRUNC or FIX	integer part of a real number
CINT	real number rounded to nearest integer
INT	real number truncated to integer closest to zero

Please note that the largest factorial allowed is 170.569398315538748, but you can work with Log factorials via the LOG! function, e.g. LOG!(171).

Arithmetic Operators
^	exponentiation (to the power of)
+	addition
-	subtraction
*	multiplication
/	division
\	integer division

Calculations give an order of priority to arithmetic operators; this must be considered when entering expressions. For example, the result of the expression "6 - 3/2" is 4.5 and not 1.5 because division takes priority over subtraction.

Priority of arithmetic operators in descending order

Exponentiation (^ or **)
Negation (-X) (Exception = x^-y; i.e. 4^-2 is 0.0625 and not -16)
Multiplication and Division (*, /)
Integer Division (\)
Addition and Subtraction (+, -)

Trigonometric Functions
ARCCOS	arc cosine
ARCCOSH	arc hyperbolic cosine
ARCCOT	arc cotangent
ARCCOTH	arc hyperbolic cotangent
ARCCSC	arc cosecant
ARCCSCH	arc hyperbolic cosecant
ARCTANH	arc hyperbolic tangent
ARCSEC	arc secant
ARCSECH	arc hyperbolic secant
ARCSIN	arc sine
ARCSINH	arc hyperbolic sine
ATN	arc tangent
COS	cosine
COT	cotangent
COTH	hyperbolic cotangent
CSC	cosecant
CSCH	hyperbolic cosecant
SIN	sine
SINH	hyperbolic sine
SECH	hyperbolic secant
SEC	secant
TAN	tangent
TANH	hyperbolic tangent

To convert degrees to radians, multiply degrees by pi/180. To convert radians to degrees, multiply radians by 180/pi.

Logical Functions
AND	logical AND
NOT	logical NOT
OR	logical OR
<	less than
=	equal to
>	greater than
<> (also ><)	not equal to
>= (also =>)	greater than or equal to
<= (also =<)	less than or equal to
true	expression outcome is true
false	expression outcome is false