Displaying 20 results from an estimated 20000 matches similar to: "Efficient ways of merging data frames"
2010 Sep 12
1
non-integer key for data.table
Hi all,
Say if I have a data table which consists of 4 column: itemID, location and
price, which location is a text field and itemID and location together forms
the primary keys.
when I tried to run setkey (DT, itemID, location), I got the following
message:
Error in setkey (DT, itemID, location) :
All keyed columns must be storage mode integer
Is there any way I could define a non-numerical
2010 Jun 07
2
Computing day-over-day log return for a matrix containing multiple time series
Hi all,
Thanks a lot for anyone's help in advance.
I am trying to find a way to compute the day-to-day return (log return) from
a n x r matrix containing, n different stocks and price quotes over r days.
The time series of prices are already split by using unstack function.
For the result, I would like to see a n x (r-1) matrix, where by each entry
is the day-over-day return of
2012 Apr 13
5
Merging two data frames with different columns names
I am trying to merge two data frames, but one of the column headings are
different in the two frames. How can I rjoin or rbind the tho frames?
Johnny
# Generate 2 blocks by confounding on abc
d1 <- conf.design(c(1,1,1), p=2, block.name="blk", treatment.names =
c("A","B","C"))
d2 <- conf.design(c(1,1,1), p=2, block.name="blk",
2011 Jan 30
1
SMA and EMA in package TTR
Hi,
Just wondering for the SMA and EMA in package TTR, is it possible to me to
code it so that, say if I need to calculate SMA (x, n=100), when the sample
size is less than 100, it will give me the SMA (x, k) where k is the sample
size of the data? Right now it only gives me an invalid n error.
Thanks!
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Which is the easiest (most elegant) way to force "aov" to treat numerical variables as categorical ?
2010 Jun 14
2
Which is the easiest (most elegant) way to force "aov" to treat numerical variables as categorical ?
Hi R help,
Hi R help,
Which is the easiest (most elegant) way to force "aov" to treat numerical variables as categorical ?
Sincerely, Andrea Bernasconi DG
PROBLEM EXAMPLE
I consider the latin squares example described at page 157 of the book:
Statistics for Experimenters: Design, Innovation, and Discovery by George E. P. Box, J. Stuart Hunter, William G. Hunter.
This example use
2009 Feb 17
1
merging files with different structures
Hello list,
Thanks in advance for any help.
I have many (approx 20) files that I have merged. For example
d1<-read.csv("AlleleReport.csv")
d2<-read.csv("AlleleReport.csv")
m1 <- merge(d1, d2, by = c("IND", intersect(colnames(d1), colnames(d2))),
all = TRUE)
m2 <- merge(m1, d3, by = c("IND", intersect(colnames(m1), colnames(d3))),
all =
2017 Oct 30
2
Problems in communication with Mustek PowerMust 1060 LCD
System: Cenots Linux 6.9
Application: nut-2.7.5-0.20170613gitb1314c6 [with usb 0.1 from distro]
Device: Mustek PowerMust 1060 LCD
Comunication log file: dump.txt
We are looking at the possibility of successful communicating with this
device UPS Mustek PowerMust 1060 LCD.
PS: wolfy on the list gives me assistance and i can install any new
compiled nut version from sources.
Thanks,
Catalin.
2008 Apr 09
2
fuzzy merge
Hi,
I would like to merge two data frames. It is just that I want the merging to be done with some kind of a fuzzy criterion. Let me explain.
My first data frame looks like this :
ID1 time1 dt
1 2008-01-02 13:11 10
2 2008-01-02 14:20 20
3
2013 Feb 07
1
Merging data in arrays
Dear All,
Here is a hypothetical sample (sorry for the clumsy code):
A1 <- matrix(1:5, nrow=5, ncol=1)
A2 <- matrix(6:10, nrow=5, ncol=1)
A3 <- matrix(11:15, nrow=5, ncol=1)
A4 <- matrix(16:20, nrow=5, ncol=1)
A5 <- matrix(21:25, nrow=5, ncol=1)
A6 <- matrix(26:30, nrow=5, ncol=1)
B1 <- matrix(c(A1, A2, A3), nrow=5, ncol=3)
B2 <- matrix(c(A2, A3, A4), nrow=5, ncol=3)
B3
2010 Apr 22
2
Compare two data frames
I wonder if there is a more efficient way to do this task. Suppose I have two data frames, such as
d1 <- data.frame(x = c(1,2,3), y = c(4,5,6), z = c(7,8,9))
d2 <- d1[, c('y', 'x')]
The first dataframe d1 has more variables than d2 and the variable columns are in a different order.
So, what I want to do is compare the two frames on the variables that are common between
2017 Jun 23
4
R version 3.3.2, Windows 10: Applying a function to each possible pair of rows from two different data-frames
For certain reason, the content was not visible in the last mail, so posting it again.
Dear Members,
I have two different dataframes with a different number of rows. I need to apply a set of functions to each possible combination of rows with one row coming from 1st dataframe and other from 2nd dataframe. Though I am able to perform this task using for loops, I feel that there must be a more
2009 Feb 26
2
Merge question
Hi:
I am a new R user. I have the following question and would appreciate your input
Data1 (data frame 1)
p1,d1,d2 (p1 is text and d1 and d2 are numeric)
xyz,10,25
Data2 (data frame 2)
p1,d1,d2
xyz,11,15
Now I want to create a new data frame that looks like so below. The fields d1 and s2 are summed by the product key.
Data3
p1,d1,d2
xyz,21 (sum of 10 from Data1 and 11 from Data2),40 (sum of 25
2017 Jun 23
0
R version 3.3.2, Windows 10: Applying a function to each possible pair of rows from two different data-frames
Hello,
The obvious way would be to preallocate the resulting data.frame, to
expand an empty one on each iteration being a time expensive operation.
n <- nrow(expand.grid(1:nrow(D1), 1:nrow(D2)))
D4 <- data.frame(distance=integer(n),difference=integer(n))
k <- 0
for (i in 1:nrow(D1)){
for (j in 1:nrow(D2)) {
k <- k + 1
D4[k, ] <-
2017 Jun 23
1
R version 3.3.2, Windows 10: Applying a function to each possible pair of rows from two different data-frames
Hello,
Another way would be
n <- nrow(expand.grid(1:nrow(D1), 1:nrow(D2)))
D5 <- data.frame(distance=integer(n),difference=integer(n))
D5[] <- do.call(rbind, lapply(seq_len(nrow(D1)), function(i)
t(sapply(seq_len(nrow(D2)), function(j){
c(distance=sqrt(sum((D1[i,1:2]-D2[j,1:2])^2)),difference=(D1[i,3]-D2[j,3])^2)
}
))))
identical(D3, D5)
In my first answer I forgot to say that
2017 Jun 23
0
R version 3.3.2, Windows 10: Applying a function to each possible pair of rows from two different data-frames
You appear to be trying to write C code in R. Don't do this. If you
can trade off space for efficiency, the calculation can be easily
vectorized (assuming I correctly understand what you want to do, of
course).
set.seed(135) ## for reproducibility
D1<-data.frame(x=1:5,y=6:10,z=rnorm(5))
D2<-data.frame(x=19:30,y=41:52,z=rnorm(12))
D.all <-merge(D1,D2, by.x=NULL,by.y=NULL) ##
2012 Mar 14
3
merge bug fix in R 2.15.0
Is it intended that the first suffix can no longer be blank? Seems to be
caused by a bug fix to merge in R 2.15.0.
$Rdevel --vanilla
DF1 = data.frame(a=1:3,b=4:6)
DF2 = data.frame(a=1:3,b=7:9)
merge(DF1,DF2,by="a",suffixes=c("",".1"))
Error in merge.data.frame(DF1, DF2, by = "a", suffixes = c("", ".1")) :
there is already a column
2005 Sep 21
1
Identical data frames
Dear All,
Is there any R function to test if two data frames, say df1 and df2, having the same row names and the same column names are identiques?
Thanks in advance,
Bernard
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2008 May 05
3
merge numerous columns of unequal length
I have numerous objects, each containing continuous data representing the
same variable, movement rate, yet each having a different number of rows.
e.g.
d1<-as.matrix(rnorm(5))
d2<-as.matrix(rnorm(3))
d3<-as.matrix(rnorm(6))
How can I merge these three columns side-by-side in order to create a table
regardless of the difference in length? I wish to analyze the output in a
spreadsheet
2012 Dec 07
1
how to add a column from another dataset with "merge"
kiotoqq wrote
> I want to add a shorter column to my dataset with the function "merge",
> it
> should be filled with NAs wo be as long as the other colums, like this:
>
> id age
> 9 46
> 8 56
> 6 52
> 5 NA
> 4 NA
> 3 NA
> 1 NA
>
> i did this:
> pa1 <- merge(pa1, an1, by="mergeid")
>
> and it says
2006 May 01
4
efficiency in merging two data frames
I have two data sets about lots of companies' stock
and fiscal data. One is monthly data with about
144,000 lines, and the other is quaterly with about
56,000. Each data set takes different company code.
I need to merge these two together. I read both ask
cvs. And the other file with corresponding firm code.
Now I have three data sets. return$PERMNO,
account$GVKEY. id is the data frames