nhanesAttr: Returns the attributes of an NHANES data table.

In nhanesA: NHANES Data Retrieval

Returns the attributes of an NHANES data table.

Description

Returns attributes such as number of rows, columns, and memory size, but does not return the table itself.

Usage

nhanesAttr(nh_table)

Arguments

nh_table

The name of the specific table to retrieve

Details

nhanesAttr allows one to check the size and other charactersistics of a data table before importing into R. To retrieve these characteristics, the specified table is downloaded, characteristics are determined, then the table is deleted. Downloads a table from the NHANES website as is, i.e. in its entirety with no modification or cleansing. If the environment variable NHANES_TABLE_BASE was set during startup, the value of this variable is used as the base URL instead of https://wwwn.cdc.gov (this allows the use of a local or alternative mirror of the CDC data).

Value

The following attributes are returned as a list
nrow = number of rows
ncol = number of columns
names = name of each column
unique = true if all SEQN values are unique
na = number of 'NA' cells in the table
size = total size of table in bytes
types = data types of each column

Examples

bpx_e = nhanesAttr('BPX_E')
length(bpx_e)
folate_f = nhanesAttr('FOLATE_F')
length(folate_f)

nhanesA documentation built on July 4, 2024, 9:08 a.m.