Note that the filename must be enclosed in single quotes and must be spelled exactly as it exists in the UNIX system (i.e., capitalization matters).ĮXAMPLES: With data included with the program statements: It tells SAS two things: first, that the data will be coming from an external file, and second, the name of that file. The INFILE statement precedes the INPUT statement in the data step. Use this style of input when you want to enter the data directly into your program (i.e., not when reading in an external file using the INFILE statement).Ģ7 118 63 24 170 70 25 173 73 23 183 68 19 203 78 The keyword is named CARDS because years ago data fed into a computer came on real cards with holes punched to represent different characters or numbers. The CARDS statement tells SAS that the data immediately follows on the next line. The double 'at' character is used in an input statement when information for more than one observation will be located on each line. Input age sex $ salary line of data might look like this: If your data contains character variables, you must let SAS know by following the variable name in the INPUT statement with the dollar sign: The dollar sign ($) after a variable name tells SAS that the variable has character values (not numbers). However, sometimes you may want to put several observations for the variables on each line. When it has filled out the list, SAS moves on to the next line of data. SAS reads a dataset one line at a time, reading in each value and putting it into the next variable in the input statement list. Notice that column 6 is not used in this example. This statement tells SAS that the value of the variable age is found in the first two columns of each line, weight occupies columns 3-5 and height is in columns 7 and 8. It is also possible to specify the columns that the variables occupy. This is an example of using free format in naming the input variables. The variable names must follow the SAS naming rules, and a space separates the variable names in an input list. It designates the names of the variables in your dataset. The INPUT statement comes after the data statement. The name you choose is up to you, but it must conform to SAS naming conventions. This tells SAS to create a new dataset and call it hwk1. All data statements must end with a semicolon. This statement must begin your DATA step. The second style uses data from another file: it uses the INFILE statement to let SAS know where to get the file. However, the first style has the data lines inside the program, so it uses the CARDS statement. or other data manipulation statements.Įach style uses the DATA and INPUT statements. new variables, use if statements, do loops, In this part of the program, you can create new variables, use if statements, do loops. In this part of the program, you can create. Generally, the data step portion of your program will either look like this: DATA dataname INPUT varname1 varname2 (etc). INFILE statement indicates that data is in a file and the name of the file.CARDS statement indicates that data lines immediately follow.INPUT statement lists names of the variables.There are four statements that are commonly used in the DATA Step The data step transforms your raw data into a SAS dataset. Within the data step you tell SAS how to read the data and generate or delete variables and observations. The data step is used to describe and modify your data. However, when you specify filenames (as you do with the include and file SAS commands), you must type it exactly as it exists in UNIX. You can use capital or lowercase letters in your SAS variables. contain only letters, numbers, or underscores (_).You will make up your own names for your SAS datasets and variables. The data step reads data into a SAS dataset, the proc step analyzes the SAS dataset. There are two components to SAS programs: the data step and the proc step. SAS Programming From (accessed August 11, 2015) SAS Programming
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