2.2.pems.structure {pems.utils} | R Documentation |
This pages provides a brief outview description of the 'pems' object structure. It also lists some associated functions
getPEMSElement(x, pems = NULL, units = NULL, ..., fun.name="getPEMSElement", if.missing = "stop", .x = enquo(x)) getPEMSData(pems=NULL, ..., fun.name = "getPEMSData", if.missing = "stop", .pems = enquo(pems)) getPEMSConstants(pems=NULL, ..., fun.name = "getPEMSConstants", if.missing = "stop", .pems = enquo(pems)) pemsData(pems=NULL, ..., fun.name = "pemsData", if.missing = "stop", pems.name = deparse(substitute(pems))) pemsConstants(pems=NULL, ..., fun.name = "pemsConstants", if.missing = "stop", pems.name = deparse(substitute(pems))) pemsHistory(pems=NULL, ..., fun.name = "pemsHistory", if.missing = "stop", pems.name = deparse(substitute(pems)))
x |
(Required vector, typically pems.element) For |
pems |
(pems object) If supplied, the |
units |
(Optional) The units that |
... |
(Optional) Other Arguments, currently ignored. |
fun.name, if.missing, pems.name, .x, .pems |
(Various) Other options using for |
The pems
object is a managed data.frame
. It has five main components: data
,
units
, constants
, history
and tags
. data
is the main
data.frame
. Each element (named data.frame
column) is a data-series of the original
PEMS data. units
are the associated unit definitions. constants
is a list of associated
constants that are to be used with the pems
object. (The preference order is arguments given in a
call then constants
declared in the pems
object then constant
defaults held by the
pems.utils
package.) history
is a log of pems
object modifications. tags
are
any other components that the user wishes to add to a pems
object as identifiers.
getPEMSElement
gets a requested pem.element
from pems
if suppied or locally.
pemsData
and getPEMSData
get the data component of a supplied pems
object.
pemsConstants
and getPEMSConstants
get all constants locally defined for the supplied
pems
object.
pemsHistory
gets the history of supplied pems
object.
getPEMSElement
returns the requested element of a supplied pems
object as a managed vector or
pems.element
, if available. If missing, error handling is by checkIfMissing
. See
check...
for more details.)
pemsData
returns the data component of a supplied pems
object as a data.frame
.
getPEMSData
returns the data component of a supplied pems
object as a data.frame
.
pemsConstants
returns the constants component of a supplied pems
object as a list
.
getPEMSConstants
returns the constants component of a supplied pems
object as a list
.
pemsHistory
returns the history component of a supplied pems
object as a list
.
pems...
functions are in development pems
object handlers. They are intended for
convenient 'front of house' use. As part of this role, their structure will evolve over time,
so arguments and operations may change based on user feedback. Those wishing to develop
future-proof third party functions should also consider check...
functions when developing
their code. See common.calculations
for some Examples.
getPEMS...
functions are a revision of earlier pems...
pems
object handlers.
They are intended for convenient 'front of house' use.
rlang
and dplyr
functions now do all the heavy lifting for getPEMSElement
.
Karl Ropkins
rlang
and dplyr
package functions now do all the heavy lifting for getPEMSElement
.
Lionel Henry and Hadley Wickham (2018). rlang: Functions for Base Types and Core R and 'Tidyverse' Features. R package version 0.2.0. https://CRAN.R-project.org/package=rlang
Hadley Wickham, Romain Francois, Lionel Henry and Kirill Muller (2017). dplyr: A Grammar of Data Manipulation. R package version 0.7.4. https://CRAN.R-project.org/package=dplyr
See Also: check...
for check...
function equivalents; pems.generics
for pems
object class generic functions.
########### ##example 1 ########### #basic usage #using example data pems.1 #(supplied as part of pems.utils package) #pems structure pems.1 # extracting the pems.1 element velocity getPEMSElement(velocity, pems.1) ## Not run: #generic (SE) equivalents pems.1$velocity pems.1["velocity"] ## End(Not run)