![]() ![]() Regardless of the informat, date values in SAS are stored as the number of days since January 1, 1960. This is particularly useful when you have numerically coded categorical variables for example, a variable representing a multiple-choice question.įor more on defining your own formats, check out the User-Defined Formats tutorial. In addition to the built-in formats, it's possible to define your own formats in SAS. you can add, subtract, multiply, and divide them), but arbitrarily change the formatted display of those numbers without sacrificing the "numeric-ness" of the variable.įor a full list of built-in formats, see the SAS documentation: This may seem like a small matter, but it's incredibly powerful: it allows you to have variables in your dataset that function as numbers (i.e. Writing numbers as roman numerals ( ROMANw.Formatting for percentages ( PERCENTw.d format). ![]() Formatting for dollar amounts ( DOLLARw.d format).Comma formatting for large numbers ( COMMAw.d format).Here's a small selection of built-in SAS formats that can change the display of numeric variables: In addition to the above generic informats, there are also many specific display formats. SAS will not recognize the informat name without the dot. This helps SAS recognize that it is an informat name rather than a variable name. Notice that the format/informat names contain a period. In these codes, w denotes the width of the variable, and d denotes the number of decimal places. Reads in numeric data of length w with d decimal points Generically, the informat/format codes follow these patterns: Type There are three main types of built-in informats in SAS: character, numeric, and date. Built-In Formats & Informatsįormats and informats in SAS use a common set of pattern codes. So informats and formats are a shared set of common patterns for reading and writing data values - the only difference is whether we apply them at the "interpretation" stage (informats) or at the "display" stage (formats). Informats are the way we give SAS an explicit rule to follow so that it makes the right judgements.įormats, on the other hand, allow SAS to change the display value "after the fact" - i.e., once SAS knows that 12-01-99 should be interpreted as MM-DD-YY, it knows that date could also be displayed as "" or "December 1, 1999" or "1 December 1999". When reading data, SAS also must make the same judgement to interpret the true meaning of the values. But if you're in Europe or Canada, you probably write your dates using DD-MM-YY order, and therefore interpret the date as "12 January 1999". If you're in the United States, you probably write your dates using MM-DD-YY order, and would therefore interpret the date as "December 1, 1999". How do you know if I mean "December 1, 1999" or "January 12, 1999"? Suppose I tell you that a person's birthday is on 12-01-99. To understand the need for informats and formats, let's start with a simple example. In this tutorial, we'll focus on SAS's built-in formats, which mostly cover numeric, date, and character variables. In SAS, formats and informats are pre-defined patterns for interpreting or displaying data values. ![]()
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