## Reading and writing

Read and write Stata DTA files.

Read and write SAS files.

Read SPSS (SAV & POR) files. Write SAV files.

Read and write SAS transport files

## Labelled vectors

SAS, SPSS, and Stata share a simply concept of “labelled” vectors, which are similar to factors but a little more general. The `labelled()`

class provides a natural representaion in R.

Convert input to a factor.

Labelled vectors for SPSS

Create a labelled vector.

Print the labels of a labelled vector

## tagged_na

Both SAS and Stata supported tagged missing values, where a missing value can have multiple “types”, given by an letter from A through Z. `tagged_na()`

provides a convenient way of representing these types of missing values in R by taking advantage of the binary representation of `NA`

.

"Tagged" missing values

## Remove attributes

There are a number of SPSS/SAS/Stata features that have no direct equivalent in R. Haven preserves them so you can choose what do with them. To simply eliminate them, use one of the zap functions.

Convert empty strings into missing values.

Remove format attributes

Zap labels

Zap special missings to regular R missings