R: Getting the List of Options CTechST for 'compContourM1/2u'
getCTechSTM1/2u
R Documentation
Getting the List of Options CTechST for compContourM1/2u
Description
The functions getCTechSTM1u and getCTechSTM2u
set the default list of options CTechST for computing
all the directional (regression) quantiles by means of
compContourM1u and compContourM2u,
respectively.
Usage
getCTechSTM1u()
getCTechSTM2u()
Arguments
none
Details
Fortunately, the default list of options usually
leads to a satisfactory performance in all but very large
problems.
Value
Both getCTechSTM1u and getCTechSTM2u produce
a list with a few components whose default values are stated
below after the equality sign.
The components OutFilePrefS and getCharST
are initialized in a method-specific way.
The components CubRegWiseI, ArchAllFI,
and SkipRedI are relevant only if D2SpecI
is zero or if the dimension of directions/responses is
higher than two, i.e., if the breadth-first search algorithm
is used.
Most of the components are generated by both functions.
Nevertheless, the component SkipRedI is only generated
by getCTechSTM2u and used by
compContourM2u.
The output components are as follows:
ReportI
= 0; if some information (such as the progress
of computation) is displayed on the screen (1)
or not (0).
The display mode may slightly slow down the
computation, especially when the dimension of
responses is higher than two.
On the other hand, it shows the new value of the
quantile level (Tau) (if the input one has been
changed internally), the initial L2-normed
directional vector used (U0Vec), the
number of failures to find an initial solution
(NNotFound), the number of found initial
solutions not having the right number of clearly
nonzero coordinates (NBad), and also the
width of each layer of the breadth-first search
algorithm if it is employed.
OutSaveI
= 0; if the detailed output is stored in
file(s) into the working directory (1) or
not (0). The file output seems necessary only
for very large problems if some information
about individual cones has to be recorded
(such as all the regression quantile
hyperplanes used for the regression
quantile contour computation).
D2SpecI
= 1; this option is relevant only for bivariate
directions/responses and determines if the cones
are visited counter-clockwise (1) or by means of
the breadth-first search algorithm as in the
general case (0). The default option (1) leads
to a more precise and reliable computation than
the other.
BriefOutputI
= 1; if the brief (1) or verbose (0)
output is prepared by
compContourM1/2u.
Even the default option (1) is sufficient
for almost all common applications.
See also getCharSTM1u and
getCharSTM2u for the
description of the possible
method-specific file output in both cases.
CubRegWiseI
= 1; if the directional space is divided
into orthants investigated separately (1)
or not (0).
On the one hand, the default option (1)
splits the problem into smaller ones.
On the other hand, it also generates
some artificial cones with at least one
facet in the orthant borders.
ArchAllFI
= 1; if all the past cone facet
identifiers (1) or only those from the last
few layers (0) are stored during the computation.
The default option (1) makes the computation
more likely to terminate successfully than
the other. Unfortunately, it is also slower
and more memory demanding. If the dimension
of responses is higher than three, then
ArchAllFI = 1 is considered internally
by compContourM1/2u no matter
what the input CTechST actually says.
SkipRedI
= 0; if the information should be skipped (1)
or stored (0) also from the cones with all
non-artificial facets already known (such cones
are redundant/irrelevant with probability one
if only all the quantile regression
hyperplanes necessary for the quantile contour
computation are required from
compContourM2u).
The skipping makes the output smaller but
maybe also slightly less reliable. It also
affects the reliability of the information
regarding the inner points; see
compContourM2u.
OutFilePrefS
= ‘DQOutputM1_’/‘DQOutputM2_’;
the prefix of possible output
file name(s).
getCharST
= getCharSTM1u/getCharSTM2u; the function
computing some overall characteristics that
can be replaced with a user-defined one.
See getCharSTM1u and
getCharSTM2u for the default
choices.
Examples
##- a typical use of getCTechSTM1u:
##computing all directional 0.01-quantiles of 49 random points
##(uniformly distributed in the unit cube centered at zero)
##after changing the default settings
Tau <- 0.01
XMat <- matrix(1, 49, 1)
YMat <- matrix(runif(3*49, -0.5, 0.5), 49, 3)
CTechST <- getCTechSTM1u()
CTechST$ReportI <- 1
COutST <- compContourM1u(Tau, YMat, XMat, CTechST)