A set of predicates and assertions for checking the properties of variables, such as length, names and attributes. Most of the documentation is on the assertive page. End-users will usually want to use assertive directly.
To install the stable version, type:
install.packages("assertive.properties")
To install the development version, you first need the devtools package.
install.packages("devtools")
Then you can install the assertive.properties package using
library(devtools)
install_bitbucket("richierocks/assertive.properties")
has_attributes
checks a variable for the presence of named attributes. has_any_attributes
and has_no_attributes
check for the presence or absence of any attributes at all.
has_dims
, has_rows
, and has_cols
check for the dimensions, rows and columns respectively.
has_duplicates
and has_no_duplicates
check whether or not a vector has duplicate elements.
has_names
, has_dimnames
, has_rownames
, and has_colnames
check for various types of name.
is_atomic
, is_recursive
, and is_vector
check for these types of variables.
is_empty
, is_non_empty
, is_scalar
, and is_non_scalar
check for objects of length 0 or 1 (or objects with 0/1 element).
is_of_length
, has_elements
, and is_of_dimension
provide more general variable size checks.
are_same_length
and have_same_dims
check for two variables having the same length/dimensions.
is_null
and is_not_null
check whether an object is NULL
or not.
is_unsorted
checks for unsorted vectors.
Predicates that return a vector have two corresponding assertions. For example, has_attributes
has assert_has_all_attributes
and assert_has_any_attributes
.
Predicates returning a single logical value have one corresponding assertion. For example, is_null
has assert_is_null
.
DIM
returns the dimension of an object, and works with vectors (like NROW
and NCOL
).
n_elements
returns the number of elements in an object.