Displaying 20 results from an estimated 7000 matches similar to: "Loess fit"
2006 Jul 31
1
questions regarding spline functions
Greetings,
A couple general questions regarding the use of splines to interpolate depth
profile data.
Here is an example of a set of depths, with associated attributes for a given
soil profile, along with a function for calculating midpoints from a set of
soil horizon boundaries:
#calculate midpoints:
mid <- function(x) {
for( i in 1:length(x)) {
if( i > 1) {
a[i] = (x[i] -
2018 Jan 17
3
always allow canonicalizing to 8- and 16-bit ops?
Example:
define i8 @narrow_add(i8 %x, i8 %y) {
%x32 = zext i8 %x to i32
%y32 = zext i8 %y to i32
%add = add nsw i32 %x32, %y32
%tr = trunc i32 %add to i8
ret i8 %tr
}
With no data-layout or with an x86 target where 8-bit integer is in the
data-layout, we reduce to:
$ ./opt -instcombine narrowadd.ll -S
define i8 @narrow_add(i8 %x, i8 %y) {
%add = add i8 %x, %y
ret i8 %add
}
But on
2018 Jan 22
0
always allow canonicalizing to 8- and 16-bit ops?
Hello
Thanks for looking into this.
I can't be very confident what the knock on result of a change like that would be,
especially on architectures that are not Arm. What I can do though, is run some
benchmarks and look at that results.
Using this patch:
--- a/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -150,6 +150,9 @@
2013 Jun 19
2
Relative position between two windows
Hi,
I'm Luca from Savona, Italy.
I'm using Compiz and I'm writing an application with Xlib to draw two
windows,
let's say window_A and window_B. I would like to keep fixed the relative
position
between two established corners of them that they have when mapped.
So that if I move or resize one of the window, the other if necessary
automatically
moves to observe the condition.
2018 Jan 22
2
always allow canonicalizing to 8- and 16-bit ops?
Thanks for the perf testing. I assume that DAG legalization is equipped to
handle these cases fairly well, or someone would've complained by now...
FWIW (and at least some of this can be blamed on me), instcombine already
does the narrowing transforms without checking shouldChangeType() for
binops like and/or/xor/udiv. The justification was that narrower ops are
always better for
2013 Jun 19
0
Relative position between two windows
Hi Luca,
In recent versions of compiz (0.9.10) if you have lazy positioning on
(org.compiz.move 'lazy-positioning') other clients won't get a configure
notification until the end of the move.
This is a performance optimization to avoid a slow path on the nvidia
drivers with vsync.
If you want such notifications you need to turn this option off. Either
that or implement this as a
2010 May 05
1
Predict when regressors are passed through a data matrix
Hi everyone,
this should be pretty basic but I need asking for help as I got stuck.
I am running simple linear regression models on R with k regressors where k
> 1. In order to automate my code I packed all the regressors in a matrix X
so that lm(y~X) will always produce the results I want regardless of the
variables in X. I am new to R but I found this advice somewhere so I guess
it is
2017 Nov 16
3
Manera eficiente de añadir el valor anterior por grupo
Buenas
Tengo un Data table de la siguiente manera:
datos<-data.table(grupo=rep(c("a","b"),5),x=c(1:10),y=rnorm(10,2,1))
Lo que quiero es añadir una fila por cada grupo y en esa nueva fila, al valor de la x ponerle el valor anterior de la y
Lo que hago es añadir una nueva fila por grupo, con:
datos[,.SD[1:(.N+1)],by=grupo]
Y para añadir el valor anterior uso la función
2009 Aug 20
1
Calculating loess value
Hello,
I'm attempting to evaluate the accuracy of the probability predictions
for my model. As previously discussed here, the AUC is not a good
measure as I'm not concerned with classification accuracy but
probability accurcy.
It was suggested to me that the loess function would be a good measure
to look at.
I can see some libraries (Design) will plot the loess function as a
curve
2012 Mar 10
1
How to fit a line through the "Mountain crest", i.e., through the highest density of points - in a "loess-like" fashion.
Hi,
I'm trying to normalize data by fitting a line through the highest density
of points (in a 2D plot).
In other words, if you visualize the data as a density plot, the fit I'm
trying to achieve is the line that goes through the "crest" of the mountain.
This is similar yet different to what LOESS does. I've been using loess
before, but it does not exactly that as it takes
2009 Sep 10
1
Exporting the formula for a LOESS fit
I'm at my wit's end, and have searched all of my sources. I need to generate
a relatively large number of individual LOESS fits each month of data (I
have about 16 months of data). Fitting the polynomial is not my problem,
figuring out what the formula that describes that polynomial is. apologies
in advance if this is so simple, but I need a hand here. Thanks.
--
View this message in
2010 Oct 05
2
loess and NA
Hi everyone.
I'm trying to do a loess with missing value on independant variable.
doc = c(2.27904, 2.59536, 7.44696, NA, 6.24264, 4.58400, 5.79192, 5.39502,
7.41216, 4.09440, 4.22868, 4.24620, 5.43804, 1.95528);
distance = c(26.5,56.5, 90.3, 123.0, 147.5, 176.0, 215.7, 229.3, 252.0,
325.3, 362.0, 419.3, 454.6, 470.0);
myloess = loess(doc ~ distance, na.action = na.omit);
plot(distance,
2012 Apr 03
2
How does predict.loess work?
Dear R community,
I am trying to understand how the predict function, specifically, the
predict.loess function works.
I understand that the loess function calculates regression parameters at
each data point in 'data'.
lo <- loess ( y~x, data)
p <- predict (lo, newdata)
I understand that the predict function predicts values for 'newdata'
according to the loess regression
2007 Feb 08
1
Point estimate from loess contour plot
Hi,
I was wondering if anyone knows of a way by which one can estimate values
from a contour plot created by using the loess function? I am hoping to
use the loess contour plot as a means of interpolation to identify
the loess created values at points at pre-defined (x,y) locations.
Could anyone point me in the right direction please?
Thanks.
Laura Quinn
Institute of Atmospheric Science
School
2001 Feb 21
1
Gradient field from loess
I have a two-dimensional loess fit, and need to calculate the
gradient field from it. Even after looking at loess.c and loess.f,
I don't understand the meaning of the returned polynomial coefficients.
Or is the brute force method of using a tangential approx
to the fitted values the way to go?
Dieter Menne
---------------------------------------
Dr. Dieter Menne
Biomed Software
72074
2010 Aug 27
3
predict.loess and NA/NaN values
Hi!
In a current project, I am fitting loess models to subsets of data in
order to use the loess predicitons for normalization (similar to what
is done in many microarray analyses). While working on this I ran into
a problem when I tried to predict from the loess models and the data
contained NAs or NaNs. I tracked down the problem to the fact that
predict.loess will not return a value at all
2005 Aug 18
1
display of a loess fitted surface
Good morning,
I am Marta Colombo,student at Politecnico,Milan. I am studying local regression models and I am using loess function. My problem is that when I have a loess object I don't know how to display the fitted surface; in fact, while in S when you have a loess object you can see it writing plot(object), in R this dosen't work. Also I'd like to know if there is something like the
2007 Jul 25
3
loess prediction algorithm
Hello,
I need help with the details of loess prediction algorithm. I would like
to get it implemented as a part of a measurement system programmed in
LabView. My job is provide a detailed description of the algorithm. This
is a simple one-dimensional problem - smoothing an (x, y) data set.
I found quite a detailed description of the fitting procedure in the "white
book". It is also
2005 Jul 12
1
getting panel.loess to use updated version of loess.smooth
I'm updating the loess routines to allow for, among other things,
arbitrary local polynomial degree and number of predictors. For now,
I've given the updated package its own namespace. The trouble is,
panel.loess still calls the original code in package:stats instead of
the new loess package, regardless of whether package:loess or
package:lattice comes first in the search list. If I
2023 Mar 23
1
loess plotting problem
Thanks, John.
However, loess.smooth() is producing a very different curve compared to the
one that results from applying predict() on a loess(). I am guessing they
are using different defaults. Correct?
On Thu, 23 Mar 2023 at 20:20, John Fox <jfox at mcmaster.ca> wrote:
> Dear Anupam Tyagi,
>
> You didn't include your data, so it's not possible to see exactly what
>