# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Library General Public
# License as published by the Free Software Foundation; either
# version 2 of the License, or (at your option) any later version.
#
# This library 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 Library General Public License for more details.
#
# You should have received A copy of the GNU Library General
# Public License along with this library; if not, write to the
# Free Foundation, Inc., 59 Temple Place, Suite 330, Boston,
# MA  02111-1307  USA

# Copyrights (C)
# for this R-port:
#   1999 - 2008, Diethelm Wuertz, Rmetrics Foundation, GPL
#   Diethelm Wuertz <wuertz@itp.phys.ethz.ch>
#   www.rmetrics.org
# for the code accessed (or partly included) from other R-ports:
#   see R's copyright and license files
# for the code accessed (or partly included) from contributed R-ports
# and other sources
#   see Rmetrics's copyright file

                                                
################################################################################
# FUNCTION:                 BASIC EXTENSIONS:                                   
#  align                     aligns time series objects by approximation        
#  align.default             align default method                               
#  atoms                     Extracts atoms from 'timeSeries' object           
#  atoms.default             atoms default method
#  attach                    attach a database to the R path                    
#  attach.default            attach default method 
#  colnames<-                colnames<- has become a generic function          
#  colnames<-.default        colnames<- default method 
#  cor                       cor has become a generic function                  
#  cor.default               cor default method    
#  cov                       var has become a generic function                  
#  cov.default               var default method                          
#  log                       log has become a generic function                  
#  log.default               log default method 
#  outlier                   outlier added generic function                  
#  outlier.default           outlier default method    
#  rownames<-                rownames<- has become a generic function          
#  rownames<-.default        rownames<- default method
#  rank                      rank has become a generic function 
#  rank.default              rank default method                                                       
#  sample                    sample has become a generic function               
#  sample.default            sample default method                              
#  sort                      sort has become a generic function                 
#  sort.default              sort default method   
#  stdev                     stdev added generic function                 
#  stdev.default             stdev default method
#  termPlot                  termPlot has become a generic function                  
#  termPlot.default          termPlot default method                              
#  var                       var has become a generic function                  
#  var.default               var default method 
#  volatility                volatility has become a generic function                  
#  volatility.default        volatility default method                                                                                                                                                                                                         
################################################################################


.conflicts.OK = TRUE


# ------------------------------------------------------------------------------


align <- 
    function(x, y, xout, ...)
{   
    # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Return Value:
    UseMethod("align")
}


# ------------------------------------------------------------------------------


align.default <- 
    function(x, y, xout, method = "linear", n = 50, rule = 1, f = 0,
    ties = mean, ...)
{   
    # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Align by Approximation:
    ans = approx(x = x, y = y, xout = xout, method = method, n = n,
        rule = rule, f = f, ties = ties, ...)

    # Return Value:
    ans
}


# ------------------------------------------------------------------------------


atoms <- 
    function(x, ...)
{   
    # A function implemented by Diethelm WUertz

    # FUNCTION:

    # Return Value:
    UseMethod("atoms")
}


# ------------------------------------------------------------------------------


atoms.default <- 
    function(x, ...)
{   
    # A function implemented by Diethelm WUertz

    # FUNCTION:

    # Return Value:
    invisible(x)
}


# ------------------------------------------------------------------------------


attach <- 
    function(what, pos = 2, name = deparse(substitute(what)),
    warn.conflicts = TRUE)
{   
    # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Return Value:
    UseMethod("attach")
}


# ------------------------------------------------------------------------------


attach.default <- base::attach


# ------------------------------------------------------------------------------


"colnames<-" =
    function(x, value)
{   
    # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Return Value:
    UseMethod("colnames<-")
}


# ------------------------------------------------------------------------------


`colnames<-.default` <- base::`colnames<-`


# ------------------------------------------------------------------------------


cor <- 
    function(x, y = NULL, use = "all.obs",
    method = c("pearson", "kendall", "spearman"))
{   
    # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Return Value:
    UseMethod("cor")
}


# ------------------------------------------------------------------------------


cor.default <- stats::cor


# ------------------------------------------------------------------------------


cov <-
    function(x, y = NULL, use = "all.obs",
    method = c("pearson", "kendall", "spearman"))
{   
    # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Return Value:
    UseMethod("cov")
}


# ------------------------------------------------------------------------------


cov.default <- stats::cov


# ------------------------------------------------------------------------------


log <- 
    function(x, base = exp(1))
{   # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Return Value:
    UseMethod("log")
}


# ------------------------------------------------------------------------------


log.default <-  
    function(x, base = exp(1)) 
{
    # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Return Value:
    base::log(x, base)
}


# ------------------------------------------------------------------------------


rank <- 
    function(x, na.last = TRUE, 
    ties.method = c("average", "first", "random", "max", "min")) 
{   
    # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Return Value:
    UseMethod("log")
}


# ------------------------------------------------------------------------------


rank.default <-  
    function(x, na.last = TRUE, 
    ties.method = c("average", "first", "random", "max", "min")) 
{
    # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Return Value:
    base::rank(x, na.last = na.last, ties.method = ties.method)
}


# ------------------------------------------------------------------------------


sample <-
    function(x, ...)
{   # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Return Value:
    UseMethod("sample")
}


# ------------------------------------------------------------------------------


sample.default <-  
    function (x, size, replace = FALSE, prob = NULL, ...)
{
    # FUNCTION:
    
    base::sample(x, size, replace = replace, prob = prob)
}


# ------------------------------------------------------------------------------


if(getRversion() < "2.4.0") {

    # Note:
    # sort() has been S3 generic in 'base' since 2.4.0
    # Otherwise use something that works here

    sort <- function (x, decreasing = FALSE, ...)
    {
        if (!is.logical(decreasing) || length(decreasing) != 1)
            stop("'decreasing' must be a length-1 logical vector.\nDid you intend to set 'partial'?")
        UseMethod("sort")
    }
    
    sort.default <- function(x, decreasing = FALSE, ...) {
        if (is.object(x))
        x[order(x, decreasing = decreasing)]
        else base::sort(x, decreasing = decreasing, ...)
    }

}# endif {only for outdated R}


# ------------------------------------------------------------------------------


outlier <- 
    function(x, sd = 5, complement = TRUE, ...)
{   
    # A function implemented by Diethelm Wuertz

    # FUNCTION:

    UseMethod("outlier")
}


# ------------------------------------------------------------------------------


outlier.default <- 
    function(x, sd = 5, complement = TRUE, ...)
{   
    # A function implemented by Diethelm Wuertz

    # Description:
    #   Returns outliers

    # Arguments:
    #   x - a numeric vector
    #   sd - a numeric value of standard deviations, e.g. 5
    #       means that values larger or smaller tahn five
    #       times the standard deviation of the series will
    #       be detected.
    #   complement - a logical flag, should the outlier series
    #       or its complements be returned.
    
    # Note:
    #   This function is thought to find splits in financial
    #   price or index data. If a price or index is splitted we
    #   observe in the returns a big jump of several standard
    #   deviations.

    # FUNCTION:

    # Find Outliers:
    SD = sd * sd(x)
    if (complement) {
        ans  = x[x <= SD]
    } else {
        ans = x[x > SD]
        names(ans) = as.character(which(x > SD))
    }

    # Return Value:
    ans
}


# ------------------------------------------------------------------------------


"rownames<-" =
    function(x, value)
{   # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Return Value:
    UseMethod("rownames<-")
}


# ------------------------------------------------------------------------------


`rownames<-.default` <- base::`rownames<-`


# ------------------------------------------------------------------------------


stdev.default <-
    function(x, na.rm = FALSE)
{   
    # A function implemented by Diethelm Wuertz

    # FUNCTION:
    
    # Return Value:
    stats::sd(x = x, na.rm = na.rm)
}


# ------------------------------------------------------------------------------


stdev <- stats::sd


# ------------------------------------------------------------------------------


termPlot <-
    function(model, ...) 
{
    # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Return Value:   
    UseMethod("termPlot")
}


# ------------------------------------------------------------------------------


termPlot.default <-
function(model, ...)
{
    # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Return Value:
    stats::termplot(model, ...)
}


# ------------------------------------------------------------------------------


var <- 
    function(x, y = NULL, na.rm = FALSE, use)
{   
    # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Return Value:
    UseMethod("var")
}


# ------------------------------------------------------------------------------


var.default <- stats::var


# ------------------------------------------------------------------------------


volatility <- 
    function(object, ...)
{   
    # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Return Value:
    UseMethod("volatility")
}


# ------------------------------------------------------------------------------


volatility.default <- 
    function(object, ...)
{   
    # A function implemented by Diethelm Wuertz

    # FUNCTION:

    # Compute volatility:
    x = object
    ans = (x - mean(x))^2

    # Return Value:
    ans
}


################################################################################