dsattr {libr}

Assign Datastep Variable Attributes

Description

An object to assign attributes to a column in a datastep. The parameters allow you to set the following attributes: 'class', 'label', 'description', 'width', 'justify', and 'format'. Any other desired attributes can be set with ....

The attributes available in the dsattr class are closely aligned with those available on the dictionary object.

Usage

dsattr(
  default = NA,
  label = NULL,
  description = NULL,
  width = NULL,
  format = NULL,
  justify = NULL,
  ...
)

Arguments

default

The default value of the column. The default value can be any valid data value. Typical default values might be an empty string ("") or a zero (0). If no default value is specified, the column will be defaulted to NA.

label

The label to associate with this column. Accepts any string value. The label will appear as a column header on some data viewers and reporting packages.

description

A description for this column. Accepts any string value. The description is intended to be a longer explanation of the purpose or source of the variable.

width

The desired width for the column in number of characters.

format

The format associated with this column. See the fmtr package for more information about formatting.

justify

The desired justification for the column. This parameter is normally used only for fixed-width, character columns. Valid values are 'left', 'right', 'center', and 'centre'.

...

Any other attributes you wish to assign to this column. Pass these additional attributes as a name/value pair.

Value

The data step attributes object.

See Also

dictionary function to observe the attributes associated with a dataset. Also see the fdata function in the fmtr package for more information on formatting and rendering data frames.

Other datastep: [.dsarray(), datastep(), delete(), dsarray(), length.dsarray(), output()

Examples

library(libr)

# Create small sample dataframe
dat <- mtcars[1:10, c("mpg", "cyl")]

# Perform datastep and assign attributes
dat1 <- datastep(dat, 
                 attrib = list(mpg = dsattr(label = "Miles Per Gallon"),
                               cyl = dsattr(label = "Cylinders"),
                               mpgcat = dsattr(label = "Fuel Efficiency")),
                {
                
                  if (mpg >= 20) 
                    mpgcat = "High"
                  else 
                    mpgcat = "Low"
                
                })

# Print results                 
dat1
#                    mpg cyl mpgcat
# Mazda RX4         21.0   6   High
# Mazda RX4 Wag     21.0   6   High
# Datsun 710        22.8   4   High
# Hornet 4 Drive    21.4   6   High
# Hornet Sportabout 18.7   8    Low
# Valiant           18.1   6    Low
# Duster 360        14.3   8    Low
# Merc 240D         24.4   4   High
# Merc 230          22.8   4   High
# Merc 280          19.2   6    Low
                
# Examine label attributes
attr(dat1$mpg, "label") 
# [1] "Miles Per Gallon"

attr(dat1$cyl, "label") 
# [1] "Cylinders"

attr(dat1$mpgcat, "label")
# [1] "Fuel Efficiency"

# See labels in viewer 
# View(dat1)