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An Introduction to SAS Character Functions (including some new SAS ® 9 functions)

An Introduction to SAS Character Functions (including some new SAS ® 9 functions). Ron Cody, Ed.D. Some Functions We Will Discuss. LENGTH SUBSTR COMPBL COMPRESS VERIFY INPUT PUT TRANWRD SCAN. TRIM UPCASE LOWCASE INDEX INDEXC INDEXW SPEDIS LENGTH. Some SAS ® 9 Functions.

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An Introduction to SAS Character Functions (including some new SAS ® 9 functions)

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  1. An Introduction to SAS Character Functions (including some new SAS® 9 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 • INDEXW • SPEDIS • LENGTH

  3. Some SAS® 9 Functions • ANYDIGIT • ANYALPHA • NOTDIGIT • NOTALPHA • CATX and CATS • COMPARE • LENGTHC • LENGTHN STRIP COUNT COUNTC PROPCASE FIND FINDC

  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_length=7 length=3 display=:abc :

  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_length=3 length=3 display=:abc:

  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 @1 Name $20. #2 @1 Address $30. #3 @1 City $15. @20 State $2. @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 (SAS® 9 changes) COMPRESS (char_value <, comp_string> <,modifiers>) 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 (SAS® 9) 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,,'kd'); 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 @1 id $3. @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 @@; 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. Parsing a String data take_apart; input @1 Cost $10.; Integer = input(scan(Cost,1,' /'),8.); Num = input(scan(Cost,2,' /'),8.); Den = input(scan(Cost,3,' /'),8.); if missing(Num) then Amount = Integer; else Amount = Integer + Num/Den; datalines; 1 3/4 12 1/2 123 ; Listing of Data Set TAKE_APART Cost Integer Num Den Amount 1 3/4 1 3 4 1.75 12 1/2 12 1 2 12.50 123 123 . . 123.00

  25. Using the SCAN Function to Extract a Last Name data first_last; length last_name $ 15; input @1 name $20. @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 ;

  26. 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

  27. 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'); /*Equivalent indexc(string,'xyz') */ datalines; abczyx1xyz 1234567890 abcx1y2z39 XYZabcxyz ; string first first_c abczyx1xyz 8 4 1234567890 0 0 abcx1y2z39 0 4 XYZabcxyz 7 7

  28. Locating the Position of One String Within Another String data locate; input string $10.; first = find(string,'xyz','i'); first_c = findc(string,'xyz','i'); /* i means ignore case */ datalines; abczyx1xyz 1234567890 abcx1y2z39 XYZabcxyz ; string first first_c abczyx1xyz 8 4 1234567890 0 0 abcx1y2z39 0 4 XYZabcxyz 1 1

  29. Locating One Word in a String Function INDEXW data _null_; string = 'anything goes any where'; index = index(string,'any'); indexw = indexw(string,'any'); put index= indexw=; run; index = 1 indexw = 15 Note: You can specify delimiters for indexw in a third argument

  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 @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; length cats $ 6 catx $ 17; string1 = 'ABC '; string2 = ' XYZ '; string3 = '12345'; cats = cats(string1,string2); catx = catx('***',string1,string2,string3); run; cats = 'ABCXYZ' catx = 'ABC***XYZ***12345 Without the length statement, cats and catx would have a length of 200

  37. Some LENGTH Functions data how_long; one = 'ABC '; miss = ' '; /* char missing value */ length_one = length(one); lengthn_one = lengthn(one); lengthc_one = lengthc(one); length_two = length(miss); lengthn_two = lengthn(miss); lengthc_two = lengthc(miss); run; 3 3 6 1 0 1

  38. The COMPARE Function COMPARE(string1, string2 <,'modifiers'>) 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 data compare; input code $ @@; value = 'V30.450'; c1 = compare(code,value); c2 = compare(code,value,':i'); c3 = compare(trim(code),value,':i'); datalines; V30 V30.450 v30.4 ; Listing of Data Set COMPARE code value c1 c2 c3 V30 V30.450 -4 -4 0 V30.450 V30.450 0 0 0 v30.4 V30.450 1 -6 0

  40. The STRIP Function data _null_; length concat $ 8; file print; one = ' ABC '; two = ' XYZ '; one_two = ':' || one || two || ':'; strip = ':' || strip(one) || strip(two) || ':'; concat = cats(':',one,two,':'); put one_two= / strip= / concat=; run; one_two=: ABC XYZ : strip=:ABCXYZ: concat=:ABCXYZ:

  41. COUNT and COUNTC Functions data Dracula; /* Get it Count Dracula */ input string $20.; count_abc = count(string,'abc'); countc_abc = countc(string,'abc'); count_abc_i = count(string,'abc','i'); datalines; xxabcxABCxxbbbb cbacba ; Listing of Data Set DRACULA count_ countc_ count_ string abc abc abc_i xxabcxABCxxbbbb 1 7 2 cbacba 0 6 0

  42. Contact Information Author: Ron Cody You may download copies of the Powerpoint presentation from: www2.umdnj.edu/codyweb/biocomputing

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