hi I have a matrix (10x10) and I have to perform t tests on each row by considering first 5 elements as data set A and next 5 as data set B. This part is easy, However after one t test on each row, I have to randomly permute each column to get new values for each row and then perform another t.test. I can permute the column randomly using the function sample(x) but i am having problem in fitting this into the matrix to perform t test on the row. I would appreciate if someone can help me with this. Or is there a function to randomly get different matrix from one original matrix without having to deal with different columns? -- View this message in context: http://www.nabble.com/help-needed-tp20648304p20648304.html Sent from the R help mailing list archive at Nabble.com.
would you post reproducible code with dummy data so that we have something to start with. thanks On Sun, Nov 23, 2008 at 12:08 PM, gauravbhatti <gaurav15984 at hotmail.com> wrote:> > hi I have a matrix (10x10) and I have to perform t tests on each row by > considering first 5 elements as data set A and next 5 as data set B. This > part is easy, However after one t test on each row, I have to randomly > permute each column to get new values for each row and then perform another > t.test. I can permute the column randomly using the function sample(x) but i > am having problem in fitting this into the matrix to perform t test on the > row. I would appreciate if someone can help me with this. > Or is there a function to randomly get different matrix from one original > matrix without having to deal with different columns? > -- > View this message in context: http://www.nabble.com/help-needed-tp20648304p20648304.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >-- Stephen Sefick Let's not spend our time and resources thinking about things that are so little or so large that all they really do for us is puff us up and make us feel like gods. We are mammals, and have not exhausted the annoying little problems of being mammals. -K. Mullis
Thankyou for the quick reply
p <- array( 0, dim =c(5,100))
porig <- array( 0, dim =c(5,1))
x1 <- array( rnorm(990,mean=0,sd=1), dim =c(4,10))
x <- rbind(c(1,1.5,1.4,3,1.9,4,4.9,2.6,3.2,2.4),x1)
i = 1; j=1;
for ( i in (1:5) )
{
xorig1 = x[1,(1:5)];
xorig2 = x[1,(6:10)];
yorig = t.test(x1,x2,var.equal=TRUE);
porig[i,1] = yo[[1]];
for ( j in (1:100))
{
z = array( sample(x), dim =c(5,10))
x1 = z[1,(1:5)];
x2 = z[1,(6:10)];
y = t.test(x1,x2,var.equal=TRUE);
p[i,j] = y[[1]];
j = j + 1;
}
i = i + 1;
}
This is the code i have been able to write so far. In this case i calculate
the t values for each row initiallay and then store it in porg matrix.In
order to randomize the matrix, I use sample(x) where x is the vector
containing all elements of the matrix. I create a new matrix of same
dimensions with the ranmdomized data and then perform t tests on each row
and store t values in p. this is done 100 times.
Please comment if you think there is better way.
gauravbhatti wrote:>
> hi I have a matrix (10x10) and I have to perform t tests on each row by
> considering first 5 elements as data set A and next 5 as data set B. This
> part is easy, However after one t test on each row, I have to randomly
> permute each column to get new values for each row and then perform
> another t.test. I can permute the column randomly using the function
> sample(x) but i am having problem in fitting this into the matrix to
> perform t test on the row. I would appreciate if someone can help me with
> this.
> Or is there a function to randomly get different matrix from one original
> matrix without having to deal with different columns?
>
--
View this message in context:
http://www.nabble.com/help-needed-tp20648304p20649213.html
Sent from the R help mailing list archive at Nabble.com.
I need some help in comparing t values avalaible from two data frames. I
have two data frames with each containing a column for t valuse
For example one data frame looks like as follows
ID logFC t P.Value adj.P.Val
B
39 a39 -1.737037118 -2.861784118 0.004212637 0.3120295 -2.504407
1 a1 -1.660000000 -2.734864780 0.006240591 0.3120295 -2.729203
53 a53 1.443725119 2.378549988 0.017380880 0.4517324 -3.305806
52 a52 -1.323602459 -2.180646836 0.029209548 0.4517324 -3.591351
14 a14 -1.288769209 -2.123258747 0.033732176 0.4517324 -3.669516
58 a58 1.286212422 2.119046418 0.034086544 0.4517324 -3.675172
75 a75 -1.268523811 -2.089904273 0.036626400 0.4517324 -3.713989
I have another one like it but the order of the ID column is different as
shown below
ID logFC t P.Value adj.P.Val
B
76 a1 0.157096693 -0.258818201 0.795775514 0.9146845 -5.075035
63 a53 -0.146205781 -0.240875326 0.809651746 0.9200588 -5.077872
88 a58 0.108707988 0.179097379 0.857861240 0.9638890 -5.086083
23 a52 -0.086871304 -0.143121247 0.886194425 0.9757266 -5.089752
98 a53 0.085552023 0.140947720 0.887911243 0.9757266 -5.089947
90 a14 0.068456451 0.112782613 0.910202903 0.9868965 -5.092209
91 a75 -0.052087970 -0.085815394 0.931613169 0.9868965 -5.093904
I have to plot the t values obtained for each id against each other. Since
the order of the IDs in the two data frames is different , I am finding it
difficult to plot the t values. Can anyone help in arranging the t values in
the increasing order of the ID values like
1 a1 ..............
2 a2 ..................
2 a3 ..................
Thank you
--
View this message in context:
http://www.nabble.com/help-needed-tp20849087p20849087.html
Sent from the R help mailing list archive at Nabble.com.
gauravbhatti wrote:> ... > I have to plot the t values obtained for each id against each other. Since > the order of the IDs in the two data frames is different , I am finding it > difficult to plot the t values. Can anyone help in arranging the t values in > the increasing order of the ID values like > 1 a1 .............. > 2 a2 .................. > 2 a3 .................. >Hi gauravbhatti, Try this (assuming your data frame is named "gvb"): gvb[order(as.character(gvb[,1])),] Jim