SAS: formats/informats/types. Their differences
format, informat, sas, types
Solution
In SAS, variables have two possible types: character or numeric.
Informat is similar but a little different. It controls how SAS read data from external data sources. There are three variants, numeric, character and date/time. Citing the code you provide here, `informat=ddmmyy16.` tells SAS to read input data in a date/time format. `16` is the width. There are many informat, conditioning on like length, decimals etc.
And also, are dates (__ToDate, __FromDate ) have a numeric type? (their missing value is dot ., not quotes "")?
In SAS, missing value of character type is given double quote `""`. For numeric type, it is dot `.`. Date/time is regarded as a numeric type.
Problem
another question about formats and informats: formats are using for output (for show me and other user data in tables), so, i don't care about it, if i want read data from tables in programming way, yes? but what is informat? i have data step with code like this: ``` data Out; attrib __fromDate __ToDate informat=ddmmyy16. format=worddatx32. __name __country length = $10 ; set InputTab; /*see Dates*/ retain __fromDate .; retain __ToDate .; /*see Strings*/ retain __name ""; retain __country ""; __fromDate=coalesce(__fromDate,fromDate); __ToDate=coalesce(__fromDate,fromDate); __name=coalescec(__name,name); __country=coalescec(__country,country); run; ``` Does this code work and what type have all these vars on each statement? Am i right, that informat and type of var are similar? And also, are dates (`__ToDate`, `__FromDate` ) have a numeric type? (their missing value is dot `.`, not quotes `""`)? Thank you!