Let’s try reading these dates and see how Stata handles them. Stata was able to read those dates without a problem. Generate birthday=date(bday,"MDY") format birthday %d Infix str name 1-4 str bday 6-17 using dates2.raw Version 9 it is declared in all lower case (i.e., "mdy").
Note that, asĭiscussed above, for Stata version 10 the order of the date is declared in upper We can try using the syntax from above to read in our new dates. It is always a month day year separated by a delimiter (e.g., space slash dot or dash). These dates are messy, but they are consistent. For example, consider the file dates2.raw. The date() function is very flexible and can handle dates written in almost any We can tell Stata that birthday should be displayed using the %d format to make itĮasier for humans to read. Of days from which is convenient for the computer storing and performing dateĬomputations, but is difficult for you and I to read. The value of birthday for John is 0Īnd the value of birthday for Mark is -207. The values for birthday may seem confusing. Let’s have a look at both bday and birthday. In Stata version 10: generate birthday=date(bday,"DMY") In Stata version 9: generate birthday=date(bday,"dmy") (Unless otherwise noted, all other Stata commands on this page So we use "DMY" (or "dmy" if you are using Stata 9) within the date() command. Our data are in the order day, month, year, Year (e.g., "DMY") but lower case if you want to specify hours, minutes or In Stata 9 it should be lowerĬase (e.g., "dmy") and in Stata 10, it should be upper case for day, month, and Theĭifference is in how the pattern is specified. Slightly different depending on which version of Stata you are using. The example below creates a date variable calledīirthday from the character variable bday. You can generate a date version of bday using the date() function. Since bday is a string variable, you cannot do any kind of date computations with it until you make aĭate variable from it.
Using the list command, you can see that the date information has been read correctly into You can read these data by typing: infix str name 1-4 str bday 6-17 using dates1.raw (4 observations read) You might have the following date data in your raw data file. Them as character strings, and then later convert them into a Stata date The trick to inputting dates in Stata is to forget they are dates, and treat
#Xline stata date format how to#
San Diego, CA: Academic Press, 61-63.This module will show how to use date variables, date functions, and date display formats in Stata.Ĭonverting dates from raw data using the "date()" function Calculate nice numbers for labeling or drawing grid lines. Stata tip 2: Building with floors and ceilings. There is a choice in there of 500 as a suitable step size subject-matter knowledge will often make that choice easy, or ambitious readers may wish to think how to automate a choice.Ĭox, N. See Cox (2003) for more on building with floors and ceilings. Conversely, the call to floor() rounds to the nearest multiple of 500, but always to the same value or downwards. Weight | 74 3019.459 777.1936 1760 4840The call to ceil() (think 'ceiling' if the function is new to you) rounds to the nearest multiple of 500, but always to the same value or upwards.
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