Displaying 20 results from an estimated 7000 matches similar to: "Question about curve fitting..."
2006 Mar 11
1
Non-linear Regression : Error in eval(expr, envir, enclos)
Hi..
i have an expression of the form:
model1<-nls(y~beta1*(x1+(k1*x2)+(k1*k1*x3)+(k2*x4)+(k2*k1*x5)+(k2*k2*x6)+(k3*x7)+(k3*k4*x8)+(k3*k2*x9)+(k3*k3*x10)+ (k4*x11)+(k4*k1*x12)+(k4*k2*x13)+(k4*k3*x14)+(k4*k4*x15)+(k5*x16)+(k5*k1*x17)+(k5*k2*x18)+(k5*k3*x19)+
2010 Aug 20
5
paired samples, matching rows, merge()
Hi everyone!
I'm matching two samples to create one sample that have
pairs of observations equal for the k1 variable. Merge()
doesn't work because I dont't want to recycle the values.
x <- data.frame(k1=c(1,1,2,3,3,5),
k2=c(20,21,22,23,24,25))
x
y <- data.frame(k1=c(1,1,2,2,3,4,5,5),
k2=c(10,11,12,13,14,15,16,17))
y
merge(x,y,by="k1")
k1 k2.x k2.y
1 1 20
2007 Oct 23
1
How to avoid the NaN errors in dnbinom?
Hi, The code below is giving me this error message:
Error in while (err > eps) { : missing value where TRUE/FALSE needed
In addition: Warning messages:
1: In dnbinom(x, size, prob, log) : NaNs produced
2: In dnbinom(x, size, prob, log) : NaNs produced
I know from the help files that for dnbinom "Invalid size or prob will
result in return value NaN, with a warning", but I am not able
2007 Oct 24
1
Error in nls model.frame
Error in model.frame
When I run the following nls model an error message appears and I dont
know how to solve that. Could you help me??
mat = c(1,2,3,4,5,6,7,8,9,12,16,24,36,48,60)
for (i in 1:length(j30)) {
bliss = nls(c(j[i,1:length(mat)]) ~ b0 + b1*((1-exp(-k1*mat))/(k1*mat)) +
b2*(((1-exp(-k2*mat))/(k2*mat))-exp(-k2*mat)),
start = list(k1=0.1993, k2=0.1993, b0= 22.0046,
2018 Feb 25
2
include
HI Jim and all,
I want to put one more condition. Include col2 and col3 if they are not
in col1.
Here is the data
mydat <- read.table(textConnection("Col1 Col2 col3
K2 X1 NA
Z1 K1 K2
Z2 NA NA
Z3 X1 NA
Z4 Y1 W1"),header = TRUE,stringsAsFactors=FALSE)
The desired out put would be
Col1 Col2 col3
1 X1 0 0
2 K1 0 0
3 Y1 0 0
4 W1 0 0
6 K2 X1
2018 Feb 25
0
include
Jim has been exceedingly patient (and may well continue to be so), but this smells like "failure to launch". At what point will you start showing your (failed) attempts at solving your own problems so we can help you work on your specific weaknesses and become self-sufficient?
--
Sent from my phone. Please excuse my brevity.
On February 25, 2018 7:55:55 AM PST, Val <valkremk at
2004 Jan 22
4
Fitting compartmental model with nls and lsoda?
Dear Colleagues,
Our group is also working on implementing the use of R for pharmacokinetic compartmental analysis. Perhaps I have missed something, but
> fit <- nls(noisy ~ lsoda(xstart, time, one.compartment.model, c(K1=0.5, k2=0.5)),
+ data=C1.lsoda,
+ start=list(K1=0.3, k2=0.7),
+ trace=T
+ )
Error in eval(as.name(varName), data) : Object
2014 Dec 04
2
[PATCH v2] v2v: When picking a default kernel, favour non-debug kernels over debug kernels (RHBZ#1170073).
---
v2v/convert_linux.ml | 18 +++++++++++++++---
1 file changed, 15 insertions(+), 3 deletions(-)
diff --git a/v2v/convert_linux.ml b/v2v/convert_linux.ml
index f670812..39a520c 100644
--- a/v2v/convert_linux.ml
+++ b/v2v/convert_linux.ml
@@ -49,13 +49,14 @@ type kernel_info = {
ki_modules : string list; (* The list of module names. *)
ki_supports_virtio : bool; (* Kernel has
2008 Feb 01
2
the "union" of several data frame rows
Hi,
I have a question about how to obtain the union of several data frame
rows. I'm trying to create a common key for several tests composed of
different items. Here is a small scale version of the problem. These
are keys for 4 different tests, not all mutually exclusive:
id q1 q2 q3 q4 q5 q6
1 A C
2 B D
3 A D B
4 C D B D
I would like
2004 Jan 30
1
MATLAB to R
Ladies and Gentlemen,
In MATLAB, I can write:
for J=1:M
Y(J+1)=Y(J)+ h * feval(f,T(J),Y(J));
...
In R, I can write above as:
for (J in 2:M)
{
y = y + h * f(t,y)
...
}
----
In MATLAB, I can write:
for J=1:M
k1 = feval(f,T(J),Y(J));
k2 = feval(f,T(J+1),Y(J)+ h * k1
How do I write k2 in R?
k1 = f(t,y)
k2 = ?
Thanks,
/oal
2018 Feb 25
0
include
Hi Val,
My fault - I assumed that the NA would be first in the result produced
by "unique":
mydat <- read.table(textConnection("Col1 Col2 col3
Z1 K1 K2
Z2 NA NA
Z3 X1 NA
Z4 Y1 W1"),header = TRUE,stringsAsFactors=FALSE)
val23<-unique(unlist(mydat[,c("Col2","col3")]))
napos<-which(is.na(val23))
preval<-data.frame(Col1=val23[-napos],
2013 May 07
2
recode categorial vars into binary data
Dear R-List,
I would like to recode categorial variables into binary data, so that all values above median are coded 1 and all values below 0, separating each var into two equally large groups (e.g. good performers = 0 vs. bad performers =1).
I have not succeeded so far in finding a nice solution to do that in R. I thought there might be a better way than ordering each column and recoding the
2013 May 07
2
recode categorial vars into binary data
Dear R-List,
I would like to recode categorial variables into binary data, so that all values above median are coded 1 and all values below 0, separating each var into two equally large groups (e.g. good performers = 0 vs. bad performers =1).
I have not succeeded so far in finding a nice solution to do that in R. I thought there might be a better way than ordering each column and recoding the
2010 Jul 24
1
Doubt about a population competition function
Hi,
I'm doing a function that describe two populations in competition.
that's the function that i wrote:
exclusao<-function(n10, n20, k1, k2, alfa, beta, t){
n1<-k1-(alfa*n20)
n2<-k2-(beta*n10)
if(t==0){plot(t, n10, type='b', xlim=range(c(1:t),c
(1:t)), ylim=range(n10, n20), xlab='tempo',
ylab='tamanho populacional')
points(t, n20, type='b',
2004 Oct 04
3
Beginners problem
Hi,
I'm new to R and have a problem with a little test program (see below).
Why doesn't <<- in function rk4
assign the new value to y so that it is seen in rktest. I thought that
<<- does exactly this. But it seems that I
didn't get it right. I would be very appreciative for an explanation of
that behaviour of <<-. I know how to
write the whole thing so that it
2005 Oct 24
2
(small) bug in nb_decode?
Hi,
So I got a crash on the following code:
k1=SUBMODE(lpc_enh_k1);
k2=SUBMODE(lpc_enh_k2);
which in the newer codebase is:
bw_lpc(SUBMODE(lpc_enh_k1), st->interp_qlpc, awk1, st->lpcSize);
bw_lpc(SUBMODE(lpc_enh_k2), st->interp_qlpc, awk2, st->lpcSize);
I am not sure if the newer code will have the same issue but the
following check is
2018 Feb 25
3
include
Thank you Jim,
I read the data as you suggested but I could not find K1 in col1.
rbind(preval,mydat) Col1 Col2 col3
1 <NA> <NA> <NA>
2 X1 <NA> <NA>
3 Y1 <NA> <NA>
4 K2 <NA> <NA>
5 W1 <NA> <NA>
6 Z1 K1 K2
7 Z2 <NA> <NA>
8 Z3 X1 <NA>
9 Z4 Y1 W1
On Sat, Feb 24, 2018 at 6:18 PM, Jim
2011 Jul 27
2
fitting sine wave
Dear R-helpers
?
I have 7 data points that I want to fit a continuous curve to, that should look similar to a sine wave
My data points would mark the local minima and maxima respectively.
This is what I?ve got so far. And I would keep doing so, but sadly nls() then says that it has reached the maximum number of Iterations?
?
2009 May 13
2
ode first step
Hi all,
I try to assess the parameters (K1,K2) of a model that describes the
adsorption of a molecule onto on adsorbent.
equation: dq/dt = K1*C*(qm-q)-K2*q
I know the value of 'qm' and I experimentally measure the variables 'q',
'C', and the time 't'.
t C q
1 0 144.05047 0.0000000
2 565 99.71492 0.1105625
3 988 74.99426
2012 Mar 02
5
Calculation of standard error for a function
Dear list,
If I know the standard error for k1 and k2, is there anything I can call in
R to calculate the standard error of k1/k2? Thanks.
Jun
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