SAS PROGRAMMING
                                     HANDOUT #6
                                   SAS FUNCTIONS

      SAS allows many functions to be used in the data step, for example:

+,-,/,*                       plus, minus, divide, multiply
ABS(X)                        absolute value of x
LOG(X)                        natural logarithm of x (base e)
LOG10(X)                      logarith base 10 of x
EXP(X)                        exponential of x
SQRT(X)                       computes square root of x
MEAN(X1,X2,...)               generates the mean of X1,X2...   (non-missing values)
STD(X1,X2....)                generates the standard deviation of X1,X2...
STDERR(X1,X2...)              generates the standard error of X1,X2...
MIN(X1,X2....)                generates the minimium of X1,X2...
MAX(X1,X2....)                generates the maximium value of X1,X2....
SUM(X1,X2...)                 generates the sum of X1,X2,...


INT(X)                        computes the integer part
ROUND(X)                      round off x
FLOOR(X)                      computes largest integer less than x
LAG(X)                        computes the previous x-value


COS(X), TAN(X), SIN(X)        cosine, sine, tangent of x (angle in radians)
ARCOS(X), ARSIN(X), ATAN(X)   arc-cosine, sine, tangent of x
COSH(X), SINH(X), TANH(X)     hyperbolic cosine sine, tangent of x
GAMMA(X)                      computes gamma function of x


PROBNORM(X)                   computes probs for normal,              PROBNORM(1.96)=.975
PROBCHI(X,df)                 computes probs for chisq,               PROBCHI(3.247,10)=.025
PROBT(X,df)                   computes probs for t-dist,              PROBT(2.228,10)=.975
PROBF(x,ndf,ddf)              computes probs for F-dist,              PROBF(3.33,5,10)=.95
PROBBNML(p,n,m)               computes probs for binom,               PROBBNML(.5,10,4)=.377


PROBIT(P)                     computes inverse normal values,         PROBIT(.975)=1.96
TINV(P)                       computes inverse t-values,              TINV(.975,10)=2.228
GAMINV(P,eta)                 computes inverse gammas parameter eta


RANNOR(0),NORMAL(0)           generates a random normal value mean 0, sd 1
RANBIN(0,n,p)                 generates a random binomial (n,p)
RANGAM(,0,alpha)              generates a random gamma value with parameter alpha
2*RANGAM(0,alpha)             generates a random chisquare with df=2*alpha
RANPOI(0,lamb)                generates a random Poisson with mean lamb


MDY(month,day,year)           generates a SAS date value
TODAY()                       generates todays date
DAY(date)                     generates day of month of date (also MONTH,YEAR functions)
WEEKDAY(date)                 generates the day of week (1=Sunday, etc)
ZIPNAME(zipcode)              generates the state name of the zipcode

SUBSTR                        used to truncate character variables, for example, if
                              X equals ABCDEFG then Y=SUBSTR(X,2,3) equals BCD.
                                 SUBSTR(X,1,3)='AAA';  changes X to equal AAADEFG
SCAN                          SCAN returns the nth word separted by the delimiter
                              For example if A is AB?CDE?GHIJ then B=SCAN(A,2,'?') is CDE
                              If the delimiter is not specified then it is assumed
                                    to be: blank,.,;,<,(,+,etc
                              Thus is  A  is A.BC<DEF(GH)IJ;K then  B=SCAN(A,4)  is  GH

TRIM(charvar)                Removes trailing blanks from character variables
RIGHT(charvar)               Trailing blanks moved to the beginning
LEFT(charvar)                Trailing blanks moved to the end
                               For example, if A=' ABC  '  (ie, 1 blank at beginning, and 2 at end)
                                            then TRIM(A)=' ABC',RIGHT(A)='   ABC', LEFT(A)='ABC   '

PUT(numvar,format)           Converts numeric variable to character variable.
                                For example, if date=11160, and date2=put(date,z6.) then date2='011160'
INPUT(charvar,format)        Converts character variable to numeric variable.
                                For example, if date2='011160', and date3=input(date2,mmddyy6.) then date3=10.
                                             since Jan 10,1960 is 10 days after jan 1,1960


A||B                          concantenates A and B
A||"-"||B                     puts a "-' sign between A and B

(statement)                   this is the logical function which is 1 if the statement is true
                              and 0 otherwise, for example   Y=(X>1);