https://github.com/cran/tseries
Tip revision: 9904ab805281cb299599623bc068eb3316f90f55 authored by Kurt.Hornik on 27 August 2001, 00:00:00 UTC
version 0.7-6
version 0.7-6
Tip revision: 9904ab8
finance.R
## Copyright (C) 1997-2001 Adrian Trapletti
##
## 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, 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.
##
## A copy of the GNU General Public License is available via WWW at
## http://www.gnu.org/copyleft/gpl.html. You can also obtain it by
## writing to the Free Software Foundation, Inc., 59 Temple Place,
## Suite 330, Boston, MA 02111-1307 USA.
##
## Financial time series analysis
##
portfolio.optim <- function (x, ...) UseMethod ("portfolio.optim")
portfolio.optim.ts <-
function (x, ...)
{
if(!is.ts(x))
stop("method is only for time series")
if(NCOL(x) == 1)
stop("x is not a multivariate time series")
res <- portfolio.optim.default(as.matrix(x), ...)
res$px <- ts(res$px, start = start(x), frequency = frequency(x))
return(res)
}
portfolio.optim.default <-
function(x, pm = mean(x), riskless = FALSE, shorts = FALSE,
rf = 0.0, reslow = NULL, reshigh = NULL, covmat = cov(x), ...)
{
if(!require(quadprog, quietly=TRUE))
stop("Package quadprog is needed. Stopping")
if(NCOL(x) == 1)
stop("x is not a matrix")
if(any(is.na(x)))
stop("NAs in x")
k <- dim(x)[2]
if(!is.matrix(covmat)) {
stop("covmat is not a matrix")
}
if((dim(covmat)[1] !=k) | (dim(covmat)[2] !=k)) {
stop("covmat has not the right dimension")
}
Dmat <- covmat
dvec <- rep(0, k)
big <- 1e+100
if(!is.null(reslow) & is.null(reshigh)) {
reshigh <- rep(big, k)
}
if(is.null(reslow) & !is.null(reshigh)) {
reslow <- -rep(big, k)
}
if(!is.null(reslow)) {
if(!is.vector(reslow)) {
stop("reslow is not a vector")
}
if(length(reslow) != k) {
stop("reslow has not the right dimension")
}
}
if(!is.null(reshigh)) {
if(!is.vector(reshigh)) {
stop("reshigh is not a vector")
}
if(length(reshigh) != k) {
stop("reshigh has not the right dimension")
}
}
if(riskless) {
a1 <- apply(x, 2, mean)-rf
if(shorts) {
a2 <- NULL
b2 <- NULL
}
else {
a2 <- matrix(0, k, k)
diag(a2) <- 1
b2 <- rep(0, k)
}
if(!is.null(reslow) & !is.null(reshigh)) {
a3 <- matrix(0, k, k)
diag(a3) <- 1
Amat <- t(rbind(a1, a2, a3, -a3))
b0 <- c(pm-rf, b2, reslow, -reshigh)
}
else {
Amat <- t(rbind(a1, a2))
b0 <- c(pm-rf, b2)
}
res <- solve.QP(Dmat, dvec, Amat, bvec=b0, meq=1)
}
else {
a1 <- rep(1, k)
a2 <- apply(x, 2, mean)
if(shorts) {
if(!is.null(reslow) & !is.null(reshigh)) {
a3 <- matrix(0, k, k)
diag(a3) <- 1
Amat <- t(rbind(a1, a2, a3, -a3))
b0 <- c(1, pm, reslow, -reshigh)
}
else {
Amat <- t(rbind(a1, a2))
b0 <- c(1, pm)
}
}
else {
a3 <- matrix(0, k, k)
diag(a3) <- 1
b3 <- rep(0, k)
if(!is.null(reslow) & !is.null(reshigh)) {
Amat <- t(rbind(a1, a2, a3, a3, -a3))
b0 <- c(1, pm, b3, reslow, -reshigh)
}
else {
Amat <- t(rbind(a1, a2, a3))
b0 <- c(1, pm, b3)
}
}
res <- solve.QP(Dmat, dvec, Amat, bvec=b0, meq=2)
}
y <- t(res$solution%*%t(x))
ans <- list(pw = res$solution, px = y, pm = mean(y), ps = sd(y))
return(ans)
}
get.hist.quote <-
function(instrument = "^gdax", start, end,
quote = "Open", provider = "yahoo", method = "auto")
{
if(missing(start)) start <- "1991-01-02"
if(missing(end)) end <- format(Sys.time() - 86400, "%Y-%m-%d")
provider <- match.arg(provider)
start <- as.POSIXct(start, tz = "GMT")
end <- as.POSIXct(end, tz = "GMT")
if(provider == "yahoo") {
url <- paste("http://chart.yahoo.com/table.csv?s=",
instrument,
format(start, "&a=%m&b=%d&c=%Y"),
format(end, "&d=%m&e=%d&f=%Y"),
"&g=d&q=q&y=0&z=",
instrument,
"&x=.csv",
sep = "")
destfile <- tempfile()
status <- download.file(url, destfile, method = method)
if(status != 0) {
unlink(destfile)
stop(paste("download error, status", status))
}
status <- scan(destfile, "", n = 1, sep = "\n", quiet = TRUE)
if(substring(status, 1, 2) == "No") {
unlink(destfile)
stop(paste("No data available for", instrument))
}
x <- read.table(destfile, header = TRUE, sep = ",")
unlink(destfile)
nser <- pmatch(quote, names(x)[-1]) + 1
if(any(is.na(nser)))
stop("This quote is not available")
n <- nrow(x)
## Yahoo currently formats dates as `26-Jun-01', hence need C
## LC_TIME locale for getting the month right.
lct <- Sys.getlocale("LC_TIME")
Sys.setlocale("LC_TIME", "C")
on.exit(Sys.setlocale("LC_TIME", lct))
dat <- gsub(" ", "0", as.character(x[, 1])) # Need the gsub?
dat <- as.POSIXct(strptime(dat, "%d-%b-%y"), tz = "GMT")
if(dat[n] != start)
cat(format(dat[n], "time series starts %Y-%m-%d\n"))
if(dat[1] != end)
cat(format(dat[1], "time series ends %Y-%m-%d\n"))
jdat <- julian(dat)
ind <- jdat - jdat[n] + 1
y <- matrix(NA, nr = max(ind), nc = length(nser))
y[ind, ] <- as.matrix(x[, nser, drop = FALSE])
colnames(y) <- names(x)[nser]
return(ts(y, start = jdat[n], end = jdat[1]))
}
else stop("provider not implemented")
}