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.
dsattr( default = NA, label = NULL, description = NULL, width = NULL, format = NULL, justify = NULL, ... )
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. |
The data step attributes object.
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()
,
dsarray()
,
length.dsarray()
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)