#
# xts: eXtensible time-series
#
# Copyright (C) 2008 Jeffrey A. Ryan jeff.a.ryan @ gmail.com
#
# Contributions from Joshua M. Ulrich
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
indexTZ <- function(x, ...)
{
.Deprecated("tzone", "xts")
tzone(x, ...)
}
tzone <- function(x, ...) {
UseMethod("tzone")
}
`indexTZ<-` <- function(x, value) {
.Deprecated("tzone<-", "xts")
`tzone<-`(x, value)
}
`tzone<-` <- function(x, value) {
UseMethod("tzone<-")
}
`tzone<-.xts` <-
function(x, value)
{
if (is.null(value)) {
value <- ""
}
tzone <- as.character(value)
attr(attr(x, "index"), "tzone") <- tzone
# Remove tz attrs (object created before 0.10-3)
attr(x, ".indexTZ") <- NULL
attr(x, "tzone") <- NULL
x
}
tzone.default <-
function(x, ...)
{
attr(x, "tzone")
}
`tzone<-.default` <-
function(x, value)
{
if (!is.null(value)) {
value <- as.character(value)
}
attr(x, "tzone") <- value
x
}
tzone.xts <-
function(x, ...)
{
tzone <- attr(attr(x, "index"), "tzone")
# For xts objects created pre-0.10.3
if (is.null(tzone)) {
# no tzone on the index
sq_tzone <- sQuote("tozne")
sq_both <- paste(sq_tzone, "or", sQuote(".indexTZ"))
warn_msg <-
paste0("index does not have a ", sq_tzone, " attribute")
tzone <- attr(x, "tzone")
if (is.null(tzone)) {
# no tzone on the xts object, look for .indexTZ
tzone <- attr(x, ".indexTZ")
}
if (is.null(tzone)) {
# no .indexTZ on the xts object
tzone <- ""
warn_msg <- paste0(warn_msg, "\n and xts object does not have a ",
sq_both, " attribute\n", " returning ", dQuote(tzone))
warning(warn_msg)
return(tzone)
}
sym <- deparse(substitute(x))
warning(warn_msg, "\n use ", sym,
" <- xts:::.update_index_attributes(", sym, ") to update the object")
}
return(tzone)
}
isClassWithoutTZ <-
function(tclass, object = NULL)
{
.classesWithoutTZ <- c("chron","dates","times","Date","yearmon","yearqtr")
has_no_tz <- FALSE
if (is.null(object)) {
has_no_tz <- any(tclass %in% .classesWithoutTZ)
} else {
has_no_tz <- inherits(object, .classesWithoutTZ)
}
return(has_no_tz)
}
isUTC <- function(tz = NULL) {
if (is.null(tz)) {
tz <- Sys.timezone()
}
switch(tz,
"UTC" = ,
"GMT" = ,
"Etc/UTC" = ,
"Etc/GMT" = ,
"GMT-0" = ,
"GMT+0" = ,
"GMT0" = TRUE,
FALSE)
}
check.TZ <- function(x, ...)
{
check <- getOption("xts_check_TZ")
if (!is.null(check) && !check) {
return()
}
x_tz <- tzone(x)
x_tclass <- tclass(x)
if (isClassWithoutTZ(x_tclass)) {
# warn if tzone is not UTC or GMT (GMT is not technically correct, since
# it *is* a timezone, but it should work for all practical purposes)
if (!isUTC(x_tz)) {
warning(paste0("object index class (", paste(x_tclass, collapse = ", "),
") does not support timezones.\nExpected 'UTC' timezone, but tzone is ",
sQuote(x_tz)), call. = FALSE)
} else {
return()
}
}
x_tz_str <- as.character(x_tz)
sys_tz <- Sys.getenv("TZ")
if (!is.null(x_tz) && x_tz_str != "" && !identical(sys_tz, x_tz_str)) {
msg <- paste0("object timezone ('", x_tz, "') is different ",
"from system timezone ('", sys_tz, "')")
if (is.null(check)) {
# xts_check_TZ is NULL by default
# set to TRUE after messaging user how to disable the warning
msg <- paste0(msg, "\n NOTE: set 'options(xts_check_TZ = FALSE)' ",
"to disable this warning\n",
" This note is displayed once per session")
options(xts_check_TZ = TRUE)
}
warning(msg, call. = FALSE)
}
}
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