Displaying 20 results from an estimated 1000 matches similar to: "date and matrices"
2013 Feb 19
1
data format
Hi,
Try this:
el<- read.csv("el.csv",header=TRUE,sep="\t",stringsAsFactors=FALSE)
?elsplit<- split(el,el$st)
?
datetrial<-data.frame(date1=seq.Date(as.Date("1930.1.1",format="%Y.%m.%d"),as.Date("2010.12.31",format="%Y.%m.%d"),by="day"))
elsplit1<- lapply(elsplit,function(x)
2008 Oct 03
2
suggestions for plotting 5000 data points
Dear all,
I have a collection of 5000 entries which represent the evolutionary
rates of 3 animals.
I would like to show the differences between the rates of all 3
animals and have tried using the function parallel (from the lattice
package) and pairs() function.
The parallel function would have been perfect save for the large
number of data (5000). The pairs() function doesn't show
2009 Sep 09
2
Matrix multiplication and random numbers
Dear All
I new to using R and am struggling with some matrix multiplication.
I have two matrices, one containing random numbers, these are multiplied
together to get another matrix which is different each time. When I put in
another for loop to repeat this process a multiple times the matrices are
all the same. I?m sure there is a way to keep the randomness of the
different matrices but I think
2010 Mar 29
2
Need help on matrix manipulation
Dear all,
Ket say I have 3 matrices :
mat1 <- matrix(rnorm(16), 4)
mat2 <- matrix(rnorm(16), 4)
mat3 <- matrix(rnorm(16), 4)
Now I want to merge those three matrices to a single one with dimension
4*3=12 and 4 wherein
on resulting matrix, row 1,4,7,10 will be row-1,2,3,4 of "mat1", row
2,5,8,11 will be row-1,2,3,4 of "mat2" and row 3,6,8,12 will be row-1,2,3,4
of
2013 Feb 01
2
Nested loop and output help
Hello Everyone,
My name is Thomas and I have been using R for one week. I recently found
your site and have been able to search the archives of posts. This has
given me some great information that has allowed me to craft an initial
design to an inquiry I would like to make into the breakdown of McNemar's
test. I have read an intro to R manual and the posting guides and hope I am
not violating
2005 Apr 29
1
na.action
Hi,
I had the following code:
testp <- rcorr(t(datcm1),type = "pearson")
mat1 <- testp[[1]][,] > 0.6
mat2 <- testp[[3]][,] < 0.05
mat3 <- mat1 + mat2
The resulting mat3 (smaller version) matrix looks like:
NA 0 0 0
0 NA 0 NA
0 0 NA 2
0 0 2 NA
To get to the number of times a '2' appears in the rows, I was
2008 Aug 29
2
Newbie: Examples on functions callling a library etc.
Hello
R is pretty new to me. I need to write a function that returns three
matrices of different dimensions. In addition, I need to call a function
from a contributed package with the function. I have browsed several
manuals and docs but the examples on them are either very simple or
extremely hard to follow.
Many thanks
Ed
[[alternative HTML version deleted]]
2010 Jan 27
1
How to sort data.frame
Dear R heleprs
Suppose I have following data
Scenarios
combination_names
series1
series2
Sc1
MAT2 GAU1
7.26554
8.409778
Sc2
MAT2 GAU2
7.438128
8.130275
Sc3
MAT3 GAU1
8.058422
8.06457
Sc4
MAT1 GAU2
8.179855
8.022071
Sc5
MAT3 GAU2
8.184033
8.191831
Sc6
MAT3 GAU2
7.50312
8.232425
Sc7
MAT1 GAU2
7.603291
8.200993
Sc8
MAT1 GAU1
8.221755
8.380097
Sc9
MAT3 GAU2
7.904908
2009 May 19
3
how to calculate means of matrix elements
useR's,
I have several matrices of size 4x4 that I want to calculate means of their
respective positions with. For example, consider I have 3 matrices given by
the code:
mat1 <- matrix(sample(1:20,16,replace=T),4,4)
mat2 <- matrix(sample(-5:15,16,replace=T),4,4)
mat3 <- matrix(sample(5:25,16,replace=T),4,4)
The result I want is one matrix of size 4x4 in which position [1,1] is the
2010 Jan 29
7
Simple question on replace a matrix row
Hello, I have a matrix mat1 of dim [1,8] and mat2 of dim[30,8], I want to
replace the first row of mat2 with mat1, this is what I do:
mat2[1,]<-mat1 but it transforms mat2 in a list I don't understand, I want
it to stay a matrix...
-----
Anna Lippel
--
View this message in context: http://n4.nabble.com/Simple-question-on-replace-a-matrix-row-tp1427857p1427857.html
Sent from the R help
2009 Sep 17
3
generating unordered combinations
Hi,
I am trying to generate all unordered combinations of a set of
numbers / characters, and I can only find a (very) clumsy way of doing
this using expand.grid. For example, all unordered combinations of
the numbers 0, 1, 2 are:
0, 0, 0
0, 0, 1
0, 0, 2
0, 1, 1
0, 1, 2
0, 2, 2
1, 1, 1
1, 1, 2
1, 2, 2
2, 2, 2
(I have not included, for example, 1, 0, 0, since it is equivalent to
0, 0, 1).
I have
2010 Oct 14
1
rbind ing matrices and resetting column numbers
Sorry for the verbose example. I want to row bind two matrices, and all works except I want the column labelled "row" to be sequential in the new matrix, shown as "mat3" here, i.e. needs to be 1:6 and not 1:3 repeated twice. Any suggestions?
Thanks
J
> colnm1 <- c("row","ti","counti")
> colnm2 <-
2003 Sep 15
2
Persp and color
How can I control de "wrap-around" color behaviour in the persp
function ?
I am using something like :
persp(bb[1:100,2:97], col= rainbow(8,start=0.1, end=0.8)))
Depending on the rainbow length value I get several "wrap-around" blocks of
the selected color range...something that I wanted to avoid...
My idea is to use the color in order to make a separation from a
certain
2010 Mar 02
2
turn character string into unevaluated R object
Hi,
How to turn a character string into an unevaluated R object? I want to load some files in a directory into data matrix R objects. I could do this with read.table and assign (see below). Then, I want to turn the character string representing a file name (the evaluated expression of i) into an unevaluated R object. Basically, I want to create matrices whose names are the same as the related file
2012 Nov 12
5
Matrix to data frame conversion
I have a matrix which I wanted to convert to a data frame. As I could not
succeed and resorted to export to csv and reimport it again. Why did I fail
in the attempt and how can I achieve what I wanted without this
roundabouts?
The original matrix:
> str(comb_model0)
num [1:90, 1:4] 3.5938 0.0274 0.0342 0.0135 0.0207 ...
- attr(*, "dimnames")=List of 2
..$ : chr [1:90]
2013 Feb 15
2
data formatting
Dear Eliza,
Try this:
Lines1<-readLines(textConnection("1911.01.01?????? 7.87
1911.01.02?????? 9.26
1911.01.03?????? 8.06
1911.01.04?????? 8.13
1911.01.05????? 12.90
1911.02.06?????? 5.45
1911.02.07?????? 3.26
1911.03.08?????? 5.70
1911.03.09?????? 9.24
1911.04.10?????? 7.60
1911.05.11????? 14.82
1911.05.12????? 14.10
1911.06.13?????? 7.87
1911.06.14?????? 9.26
2007 Nov 14
2
Generating these matrices going backwards
I have generated the following:
x=
E1 E2 E3
D1 0 0 1
D2 1 0 3
D3 0 2 0
y=
E1 E2 E3
D1 0 0 1.75
D2 1.75 0 1.3125
D3 0 3.5 0
Where x and y are linked by:
y =sum(x) * x / (rowSums(x)%o%colSums(x))
N=x[x[1:3,]>0]
R=y[y[1:3,]>0]
Now suppose I ONLY
2013 Jan 04
2
Working with Matrix
Hello again,
Let say I have 2 matrices which equal number of columns but different
number of rows like:
Mat1 <- matrix(1:20, 4, 5)
Mat2 <- matrix(1:25, 5, 5)
Now for each column 1-to-5 I need to fetch the corresponding columns
of these 2 matrices and add the corresponding elements (ignoring NA
values if any). Therefore for the 1st column I need to do:
(1+1), (2+2),...,(4+4), (NA+5)
and
2006 Jul 20
2
Timing benefits of mapply() vs. for loop was: Wrap a loop inside a function
List:
Thank you for the replies to my post yesterday. Gabor and Phil also gave
useful replies on how to improve the function by relying on mapply
rather than the explicit for loop. In general, I try and use the family
of apply functions rather than the looping constructs such as for, while
etc as a matter of practice.
However, it seems the mapply function in this case is slower (in terms
of CPU
2011 Apr 24
2
random roundoff?
On my CentOS 5 box, in a C++ program that does much arithmetic,
including numerous matrix multiplications, I have a situation in
in which the result depends on the nature of nearby I/O. Thus,
with all arithmetic done with type double, and where values
are mostly in the range [-1.0e0,+1.0e0] or nearby, I do:
cerr << "some stuff" << endl;
mat3 = matmult(mat1,mat2);
I