Simultaneous Format and Informat

[aaronh]

I came across a SAS variable the other day that had both format and informat assigned to it. (I forgot to take a screenshot)

I am just curious that what happens if the format and informat are completely incompatible? Will the variable still be displayed?

Sorry for asking a weird question...

[Kurt_Bremser]

They can be "incompatible". Think of this: data from Excel was saved incorrectly to a csv, and you have the raw numbers for dates in there. So you read with the informat 5., add '30dec1899'd, and assign the yymmddd10. format to have a SAS date column.

[aaronh]

Thank you Kurt. So if I run a proc print, what format or informat will it display?..

[Tom]

---

@aaronh wrote:
Thank you Kurt. So if I run a proc print, what format or informat will it display?..

---

It will not print either of them.

It will use the FORMAT attached to the variable to determine how to convert the values stored in the variable into the text needed to print.

[Kurt_Bremser]

---

@aaronh wrote:
Thank you Kurt. So if I run a proc print, what format or informat will it display?..

---

It will not show you the names of the formats, but it will use the assigned format to display the values.

[Tom · Accepted solution]

An INFORMAT is used to convert text to values.  Once you have a variable in a SAS dataset the informat attached to the variable is of little value anymore.  It mainly will serve as documentation of how the variable was created.

Having an INFORMAT and a FORMAT which share the same name is possible, but does not mean they are compatible or even related.  In real usage it is probably rare that variables would have matching format and informat names anyway, other than the many that should have neither an informat or a format attached..  For most character variables there is no need to attach either an informat or a format.  Similarly for most numeric variables.  Unless you need to represent more than 11 significant digits or want to enforce a fixed number of decimal places on display.  The main need is for DATE, TIME and DATETIME values.  And there it is pretty normal to read the values using one format (or even one of the ANYDTxxx informats) and display with another.