SAS, Ch5, Data Transformations 7.29.18

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The ROUND Function example

NewVar=ROUND(argument<,round-off-unit>); NewVar6=round(42.65,.5); argument=is a number or numeric expression round-off-unit=is numeric and positive. If round-off-unit is not provided, argument is rounded to the nearest integer

The SCAN Function example

NewVar=SCAN(string,n<,charlist>); Second=scan(Phrase,2,', '); string=can be a character constant, variable, or expression n=specifies the nth word to extract from string charlist=lists the characters that delimit words

Automatic Numeric to Character Conversion

!! example Phone= '(' !! Area_Code !! ') ' !! Mobile; uses the best 12. format right aligns the resulting character value (fixed using the PUT function)

The CATX Function example

NewVar=CATX(separator, string-1,...string-n) separator=character string that is inserted between the concatenated string-1,...string-n arguments string-1...string-n=can be a character constant, variable, or expression. leading and trailing blanks are removed from each argument

The CEIL Function example

NewVar=CEIL(argument); x=ceil(4.4);

The COMPRESS Function example

NewVar=COMPRESS(source<,chars>); New_ID1=compress (ID);

The FLOOR Funciton example

NewVar=FLOOR(argument); y=floor(3.6);

The INT Function example

NewVar=INT(argument); z=int(3.9);

LENGTH Function example

NewVar=LENGTH(argument); ID=substr(Acct_Code,1,length(Acc_Code)-1);

the PROPCASE Function example

NewVar=PROPCASE(argument<,delimiter(s)>); name = propcase(name);

SAS Functions

a routine that performs a computation and returns a value. use arguments supplied by the user or by the operating environment an argument can be a constant, variable or any sas expression when you use a sas variable list in a sas function, use the keyword OF in front of the first variable name in the list

Concatenation Operator

an operator that joins character strings

Data Conversion

can be done in two ways: 1.automatically by allowing SAS to do it for you (add an arithmetic expression) 2.explicitly with these functions 2a.INPUT - character to numeric conversion 2b.PUT-numeric to character conversion

LOWCASE(string)

converts all letters in an argument to lowercase

UPCASE(string)

converts all letters in an argument to uppercase

the PROPCASE Funciton

converts all words in an argument to poper case, in which the first letter is uppercase and the remaining letters are lowercase argument=character constant, variable or expression delimiter=characters which separate words if omitted, the default delimiters are the blank, /, -,(,., and tab characters NewVar=is a new variable, it is created with the same length as argument

CAT Functions

converts any numeric argument to a character string by using the BEST12. format and then removing any leading blanks. No note is written to the log.

NMISS

count of missing numeric arguments

CMISS

count of missing numeric or character arguments

converting a variable example

data work.hrdata (drop=CharGross); set orion.convert(rename=(GrossPay=CharGross)); GrossPay=input(CharGross, comma6.);

CAT(string-1,...string-n)

does not remove leading or traililng blanks from the arguments before concatenating them

SAS Functions example

function-name(argument-1, argument-2...) Total=sum(qtr1, qtr2, qtr3, qtr4);

The SUBSTR Function (Right Side) example

NewVar=SUBSTR(string,start<,length>; item_type=substr(item-code,1,3); string-character constant, variable or expression start-specifies the starting position length-specifies the number of characters to extract. the substring consists of the remainder of string newVar-if a new variable, it will be created with the same length as string. to set a different length for newVar , use a LENGTH statement prior to the assignment statement

The CATX Function

joins or concatenates character strings

The TRANWRD Function example

NewVar=TRANWRD(source,target,replacement); product=Tranwrd(Product, 'Luci ', 'Lucky '); source=specifies the source string that you want to change target=specifies the string searched for in source replacement=specifies the string that replaces target

Concatenation Operator example

NewVar=string1 !! string2; Phone = '('!!area!!') '!!Number; operator can also be written as two vertical or two broken vertical bars

The INPUT Function example

NumVar=INPUT(source,informat); NVar1=input(CVar1,5.); source=contains a sas character expression informat=is the sas informat to apply to the source

CAT Functions example

Phone='(' !! put(area_code, 3.) !! ') ' !! Mobile;

The FIND Function example

Position=FIND(string,substring<,modifiers,startpos>); pos1=find(text, 'US');

The SUBSTR Function (Left Side) example

SUBSTR(string,start<,length>)=value; substr(Location,11,2)='OH'; string=specifies a character variable start=specifies the starting position to replace characters with the value length=specifies the number of characters to replace in string.

LEFT(string)

left aligns a character expression

VARNUM option in PROC CONTENTS

prints a list of the variables by their logical position in the data set

STRIP(string)

removes all leading and trailing blanks from a character string

CATS(string-1,...,string-n)

removes leading and trailing blanks from the arguments

COMPBL(string)

removes multiple blanks from a character string by translating each occurrence of two or more consecutive blanks into a single blank

The COMPRESS Function

removes the characters listed in the chars argument form the source if no chars are specified the function removes all blanks from the source

TRIM(string)

removes trailing blanks from a character string

CATT(string-1,...string-n)

removes trailing blanks from the arguments

The SUBSTR Function (Left Side)

replaces characters in a character variable

The TRANWRD Function

replaces or removes all occurrences of a given word (or a pattern of characters) within a character string. when using this function these details apply: 1. does not remove trailing blanks from target or replacement 2. if NewVar was not previously defined, it is given a length of 200 3. if the target string is not found in the source, then no replacement occurs

CHAR(string.position)

returns a single character from a specified position in a character string

The ROUND Function

returns a value rounded to the nearest multiple of the round off unit

The FLOOR Funciton

returns the greatest integer less than or equal to the argument

The INT Function

returns the integer portion of the argument

LENGTH Function

returns the length of a non-blank character string, excluding trailing blanks

The SCAN Function

returns the nth word of a character value a missing value is returned if there are fewer than n words in the string if n is negative, the function selects the word in the character string starting from the end of the string delimiters before hte first word have no effect any character or set of characters can serve as delimiters two or more contiguous delimiters are treated as a single delimiter the length of the created variable is 200 bytes a good practice is to explicitly define the length of any created variable with a LENGTH statement

The CEIL Function

returns the smallest integer greater than or equal to the argument

The INPUT Function

returns the value produced when the source is read with a specified informat used to explicitly convert character values to numeric

RIGHT(string)

right aligns a character expression

PUT Function example

CharVar=PUT(source,format); CVar1=put(NVar1,3.); source=identifies the SAS variable or constant whose value you want to reformat. This argument can be character or numeric format=contains the sas format that you want applied to the variabe or constant that is specified in the source. It msut agree with the surce in type.

Automatic Character to Numeric Conversion

sas automatically converts a character value to a numeric value when the character value is used in a numeric context, such as the following: assignment to a numeric variable an arithmetic operation logical comparison with a numeric value a function that takes numeric arguments

rename example

sas-data-set(RENAME=(od-name=new-name))

The FIND Function

searches a target string for a specified substring returns a numeric value that is: 1. the starting position of the first occurrence of substring within string, if substring is found 2. 0, if substring is not found modifiers can be: 1. I to indicate a case insensitive search 2. T to indicate to ignore trailing blanks in the string and substring values. startpos indicates where in the string to start searching for the substring.

Steps to converting a variable to another data type

steps: 1. use the rename= data set option to rename the variable that you want to convert sas-data-set(RENAME=(od-name=new-name)) 2. Use the INPUT function in an assignment statement to create a new variable with the original name of the variable that you renamed GrossPay=input(CharGross,comma6.); 3. use a drop= data set option in the data statement to exclude the original variable from the output sas data set. data work.hardata (drop=CharGross);

The SUBSTR Function (Right Side)

used to extract characters for example, can be used to create a new variable from some existing variable

PUT Function

writes values with a specific format returns the value produced when source is written with format always returns a character string


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