An Introduction to SAS Character Functions including some new V9 functions

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An Introduction to SAS Character Functions including some new V9 functions

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Use the LENGTH statement as the very first statement in the DATA STEP to declare ... truncate the longer string to the length of the shorter string. ... –

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Title: An Introduction to SAS Character Functions including some new V9 functions

1
An Introduction to SAS Character Functions
(including some new V9 functions)

Ron Cody, Ed.D.

2
Some Functions We Will Discuss

LENGTH
SUBSTR
COMPBL
COMPRESS
VERIFY
INPUT
PUT
TRANWRD
SCAN

TRIM
UPCASE
LOWCASE
INDEX
INDEXC
SPEDIS
LENGTH

3
Some V9 Functions

ANYDIGIT
ANYALPHA
NOTDIGIT
NOTALPHA
CATX and CATS
COMPARE
LENGTHC
LENGTHN

STRIP
COUNT
COUNTC
PROPCASE
INDEXW

4
Character Storage Lengths

data chars1
length string 7
string 'abc'
length length(string)
storage_length lengthc(string)
display "" string ""
put storage_length /
length /
display
run

5
SAS Log

11 data chars1
12 length string 7
13 string 'abc'
14 storage_length lengthc(string)
15 length length(string)
16 display "" string ""
17 put storage_length /
18 length /
19 display
20 run
storage_length7
length3
displayabc

6
Moving the LENGTH Statement

data chars2
string 'abc'
length string 7
storage_length lengthc(string)
length length(string)
display "" string ""
put storage_length /
length /
display
run

7
SAS Log

1 data chars2
2 string 'abc'
3 length string 7
WARNING Length of character variable string has
already been set. Use the LENGTH statement as the
very first statement in the DATA STEP to declare
the length of a character variable.
4 storage_length lengthc(string)
5 length length(string)
6 display "" string ""
7 put storage_length /
8 length /
9 display
10 run
storage_length3
length3
displayabc

8
The INPUT Function

data special
INPUT is a special function often used
for character to numeric conversion
length c_date 10 numeral 3
input c_date numeral
sas_date input(c_date,mmddyy10.)
number input(numeral,3.)
datalines
11/12/1950 123
9-15-2004 99

Listing of Data Set SPECIAL c_date numeral
sas_date number 11/12/1950 123 -3337
123 9-15-2004 99 16329 99
9
The PUT Function

data special
PUT is a special function often used
for numeric to character conversion
input sas_date number ss
c_date put(sas_date,date9.)
money put(number,dollar8.)
ss_char put(ss,ssn.)
datalines
0 1234 123456789

Listing of Data Set SPECIAL sas_date number
ss c_date money ss_char 0
1234 123456789 01JAN1960 1,234 123-45-6789
10
Converting Multiple Blanks to a Single Blank

data multiple
input 1 _at_1 Name 20.
2 _at_1 Address 30.
3 _at_1 City 15.
_at_20 State 2.
_at_25 Zip 5.
name compbl(name)
address compbl(address)
city compbl(city)
datalines
Ron Cody
89 Lazy Brook Rd.
Flemington NJ 08822
Bill Brown
28 Cathy Street
North City NY 11518

Multiple Name Address Ron
Cody 89 Lazy Brook Rd. Bill Brown 28
Cathy Street City State Zip
Flemington NJ 08822 North City NY
11518
11
How to Remove Characters from a String

data phone
input phone 15.
phone1 compress(phone)
phone2 compress(phone,'(-) ')
datalines
(908)235-4490
(201) 555-77 99

Phone phone phone1
phone2 (908)235-4490 (908)235-4490
9082354490 (201) 555-77 99 (201)555-7799
2015557799
12
Another COMPRESS Example

data social
input ss_char 11.
ss input(compress(ss_char,'-'),9.)
easy_ss input(ss_char,comma11.)
datalines
123-45-6789

ss 123456789 (numeric) ss_easy 123456789
(numeric)
13
Compress Function (v9 changes)

COMPRESS (char_value lt, comp_stringgt
lt,modifiersgt)
char_value is a SAS character value
comp_string is a character value containing the
characters to remove from char_value.
modifiers add additional characters to the list
of
characters to remove or modify the way the
function works (see next slide).

14
Compress Function Modifiers (v9)

Selected list of COMPRESS modifiers (upper- or
lowercase)
a adds upper- and lowercase letters
d adds numerals (digits)
i ignores case
k keeps listed characters instead of removing
them
s adds space (blank, tabs, lf, cr) to the list
p adds punctuation

15
Examples
For these examples, char "A C123XYZ" , phone
"(908) 777-1234"
16
Using the Compress Modifiers

data phone
input phone 15.
number compress(phone,,'dk')
datalines
(908)235-4490
(201) 555-77 99

Listing of Data Set PHONE
phone number
(908)235-4490 9082354490
(201) 555-77 99 2015557799

17
The VERIFY Function

data verify
input _at_1 id 3.
_at_5 answer 5.
position verify(answer,'abcde')
datalines
001 acbed
002 abxde
003 12cce
004 abc e

Verify id answer position 001 acbed
0 002 abxde 3 003 12cce
1 004 abc e 4
18
Watch Out for Trailing Blanks

data trailing
length string 10
string 'abc'
position verify(string,'abcde')
run

String 'abc ' Position 4 (the position
of the first trailing blank)
19
Watch Out for Trailing Blanks

data trailing
length string 10
string 'abc'
position
verify(trim(string),'abcde')
run

Position 0
20
Using VERIFY for Data Cleaning

data clean
input id
Valid ID's contain letters X,Y, or Z
and digits
if verify(trim(id),'XYZ0123456789') eq 0
then valid 'Yes'
else valid 'No'
datalines
12X67YZ
67WXYZ

Listing of Data Set CLEAN id
valid 12X67YZ Yes 67WXYZ No
21
Substring Example

data pieces_parts
input Id 9.
length State 2
state substr(id,1,2)
Num input(substr(id,7,3),3.)
datalines
NYXXXX123
NJ1234567

Listing of Data Set PIECES_PARTS Id
State Num NYXXXX123 NY 123 NJ1234567
NJ 567
22
The SUBSTR Function on the Left-Hand Side of the
Equal Sign

data pressure
input sbp dbp _at__at_
length sbp_chk dbp_chk 4
sbp_chk put(sbp,3.)
dbp_chk put(dbp,3.)
if sbp gt 160 then
substr(sbp_chk,4,1) ''
if dbp gt 90 then
substr(dbp_chk,4,1) ''
datalines
120 80 180 92 200 110

23
The SUBSTR Function on the Left-Hand Side of the
Equal Sign

Listing of Data Set PRESSURE
sbp dbp sbp_chk dbp_chk
120 80 120 80
180 92 180 92
200 110 200 110

24
Unpacking a String

data pack
input string 5.
datalines
12345
8 642
data unpack
set pack
array x5
do j 1 to 5
xj input(substr(string,j,1),1.)
end
drop j
run

Listing of Data Set UNPACK string x1 x2 x3
x4 x5 12345 1 2 3 4 5 8 642 8 .
6 4 2
25
Parsing a String

data take_apart
input _at_1 date 10.
month input(scan(date,1,'-/'),2.)
day input(scan(date,2,'-/'),2.)
year input(scan(date,3,'-/'),4.)
sas_date input(date,mmddyy10.)
format sas_date mmddyy10.
datalines
10/21/1994
3-7-1960
1251970

Listing of Data Set TAKE_APART date month
day year sas_date 10/21/1994 10 21 1994
10/21/1994 3-7-1960 3 7 1960
03/07/1960 1251970 12 5 1970 12/05/1970
26
Using the SCAN Function to Extract a Last Name

data first_last
input _at_1 name 20.
_at_22 phone 13.
extract the last name from name
last_name scan(name,-1,' ')
minus value scans from the right
datalines
Jeff W. Snoker (908)782-4382
Raymond Albert (732)235-4444
Alfred Edward Newman (800)123-4321
Steven J. Foster (201)567-9876
Jose Romerez (516)593-2377

27
Using the SCAN Function to Extract a Last Name

Names and Phone Numbers in Alphabetical Order (by
Last Name)
Name Phone Number
Raymond Albert (732)235-4444
Steven J. Foster (201)567-9876
Alfred Edward Newman (800)123-4321
Jose Romerez (516)593-2377
Jeff W. Snoker (908)782-4382

28
Locating the Position of One String Within
Another String

data locate
input string 10.
first index(string,'xyz')
first_c indexc(string,'x','y','z')
datalines
abczyx1xyz
1234567890
abcx1y2z39

Listing of Data Set LOCATE string first
first_c abczyx1xyz 8 4 1234567890
0 0 abcx1y2z39 0 4
29
Locating One Word in a StringV9 Function INDEXW

data find_word
string 'anything goes any where'
index index(string,'any')
indexw indexw(string,'any')
put index indexw
run

index 1 indexw 15
30
Changing Case

Data case
input name 15.
upper upcase(name)
lower lowcase(name)
proper propcase(name)
Datalines
gEOrge SMITH
The end

Listing of Data Set CASE name upper
lower proper gEOrge SMITH GEORGE
SMITH george smith George Smith The end
THE END the end The End
31
Substituting One Word for Another in a String

data convert
input _at_1 address 20.
Convert Street, Avenue and
Boulevard to their abbreviations
Address tranwrd(address,'Street','St.')
Address tranwrd(address,'Avenue','Ave.')
Address tranwrd(address,'Road','Rd.')
datalines
89 Lazy Brook Road
123 River Rd.
12 Main Street

Listing of Data Set CONVERT Obs Address 1
89 Lazy Brook Rd. 2 123 River Rd. 3
12 Main St.
32
Spelling distance

data compare
length string1 string2 15
input string1 string2
points spedis(string1,string2)
datalines
same same
same sam
first xirst
last lasx
receipt reciept

Listing of Data Set COMPARE string1 string2
points same same 0 same
sam 8 first xirst 40 last
lasx 25 receipt reciept 7
33
The "ANY" Functions

data find_alpha_digit
input string 20.
first_alpha anyalpha(string)
first_digit anydigit(string)
datalines
no digits here
the 3 and 4
123 456 789

Listing of Data Set FIND_ALPHA_DIGIT
first_ first_ string alpha
digit no digits here 1 0 the 3
and 4 1 5 123 456 789 0
1
34
The "NOT" FunctionsBeware of Trailing Blanks

length string 10
string '123'
position notdigit(string)
pos_trim notdigit(trim(string))
position 4 (position of first blank)
pos_trim 0

35
The "NOT" Functions

data data_cleaning
input string 20.
not_alpha notalpha(trim(string))
not_digit notdigit(trim(string))
datalines
abcdefg
1234567
abc123
1234abcd

Listing of Data Set DATA_CLEANING
not_ not_ string alpha digit abcdefg
0 1 1234567 1 0 abc123
4 1 1234abcd 1 5
36
Concatenation Functions

data join_up
string1 'ABC '
string2 ' XYZ '
string3 '12345'
cats cats(string1,string2)
catx catx('',string1,string2,string3)
run

cats 'ABCXYZ' catx 'ABCXYZ12345
37
Some LENGTH Functions

data how_long
one 'ABC '
two ' ' / character missing value /
three ' XYZ'
length_one length(one)
lengthn_one lengthn(one)
lengthc_one lengthc(one)
length_two length(two)
lengthn_two lengthn(two)
lengthc_two lengthc(two)
length_three length(three)
lengthn_three lengthn(three)
lengthc_three lengthc(three)
run

3 3 6 1 0 1 6 6 6
38
The COMPARE Function

COMPARE(string1, string2 lt,'modifiers'gt)
I ignore case
L remove leading blanks
truncate the longer string to the length of the
shorter string. The default is to pad the shorter
string with blanks before a comparison.
(Note similar to the comparison operator)

If string1 and string2 are the same, COMPARE
returns a value of 0. If the arguments differ,
the sign of the result is negative if string1
precedes string2 in a sort sequence, and positive
if string1 follows string2 in a sort sequence
The magnitude of the result is equal to the
position of the leftmost character at which the
strings differ.
39
The COMPARE Function