Internship, CRO and pharmaceutical companies, are required to SAS, a word, learn!
SAS program comprises two parts, a data and proc
SAS SAS program must be based on a keyword (keyword) at the beginning, usually end with a semicolon (semicolon), case-insensitive, you can write multiple lines
RUN write a lot of advantages, easy to read and debug
Each execution SAS generates a log, log processing and including processing results and error
File storage format libref.filename, an intermediate period (period)
Built-in logic library name: work
Connecting a fixed logic library libname test 'C: \ sas';
The name of the data set: letters or begin with an underscore, 1-32 characters
In general, SAS data set includes description section (descriptor portion) and a data portion (data portion)
A behavior of an observation unit (observation), a listed as a variable (variable)
Properties of the variable (variable attributes) include the name of name, type of type, the length of the length, format format, informat, tag label
There are character and numeric type
character missing values (NA) of the blank (blank), numeric values deletion period (period)
character accounted for the largest 32,767 bytes, numeric default 8 bytes (default length)
There format character, numeric, time, date, format variables can affect the way the value written. You can also customize the format
Two significant figures: for example 2 becomes 2.00, format is COMMA8.2 denotes the width (width) is 8, two decimal places (2 decimal places)
In the SAS data set, the variable setting permanent format. Temporary variables in the proc
When mixed with the character number, eg: $ 1,000.00, informat will enter the value read in a standard format
label a variable name as a label as you wish