I have a dataframe, where one column contains strings.
q = data.frame(number=1:2,text=c("The surcingle hung in ribands from my body.", "But a glance will show the fallacy of this idea."))
I want to use the word_stats function for each individual record.
is it possible?
text_statistic <- apply(q,1,word_stats)
this will apply word_stats() row-by-row and return a list with the results of word_stats() for every row
you can do it many ways, lapply or sapply apply a Function over a List or Vector.
word_stats <- function(x) {length(unlist(strsplit(x, ' ')))}
sapply(q$text, word_stats)
Sure have a look at the grouping.var argument:
dat = data.frame(number=1:2,text=c("The surcingle hung in ribands from my body.", "But a glance will show the fallacy of this idea."))
with(dat, qdap::word_stats(text, number))
## number n.sent n.words n.char n.syl n.poly wps cps sps psps cpw spw pspw n.state p.state n.hapax grow.rate
## 1 2 1 10 38 14 2 10 38 14 2 3.800 1.400 .200 1 1 10 1
## 2 1 1 8 35 12 1 8 35 12 1 4.375 1.500 .125 1 1 8 1
Related
I hope you are having a nice day. I would like to know if there is a way to create a permutation (rearrangement) of the values in a vector in R?
My professor provided with an assignment in which we are supposed create functions for a randomization test, one while using sample() to create a permutation and one not using the sample() function. So far all of my efforts have been fruitless, as any answer that I can find always resorts in the use of the sample() function. I have tried several other methods, such as indexing with runif() and writing my own functions, but to no avail. Alas, I have accepted defeat and come here for salvation.
While using the sample() function, the code looks like:
#create the groups
a <- c(2,5,5,6,6,7,8,9)
b <- c(1,1,2,3,3,4,5,7,7,8)
#create a permutation of the combined vector without replacement using the sample function()
permsample <-sample(c(a,b),replace=FALSE)
permsample
[1] 2 5 6 1 7 7 3 8 6 3 5 9 2 7 4 8 1 5
And, for reference, the entire code of my function looks like:
PermutationTtest <- function(a, b, P){
sample.t.value <- t.test(a, b)$statistic
perm.t.values<-matrix(rep(0,P),P,1)
N <-length(a)
M <-length(b)
for (i in 1:P)
{
permsample <-sample(c(a,b),replace=FALSE)
pgroup1 <- permsample[1:N]
pgroup2 <- permsample[(N+1) : (N+M)]
perm.t.values[i]<- t.test(pgroup1, pgroup2)$statistic
}
return(mean(perm.t.values))
}
How would I achieve the same thing, but without using the sample() function and within the confines of base R? The only hint my professor gave was "use indices." Thank you very much for your help and have a nice day.
You can use runif() to generate a value between 1.0 and the length of the final array. The floor() function returns the integer part of that number. At each iteration, i decrease the range of the random number to choose, append the element in the rn'th position of the original array to the new one and remove it.
a <- c(2,5,5,6,6,7,8,9)
b <- c(1,1,2,3,3,4,5,7,7,8)
c<-c(a,b)
index<-length(c)
perm<-c()
for(i in 1:length(c)){
rn = floor(runif(1, min=1, max=index))
perm<-append(perm,c[rn])
c=c[-rn]
index=index-1
}
It is easier to see what is going on if we use consecutive numbers:
a <- 1:8
b <- 9:17
ab <- c(a, b)
ab
# [1] 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
Now draw 17 (length(ab)) random numbers and use them to order ab:
rnd <- runif(length(ab))
ab[order(rnd)]
# [1] 5 13 11 12 6 1 17 3 10 2 8 16 7 4 9 15 14
rnd <- runif(length(ab))
ab[order(rnd)]
# [1] 14 11 5 15 10 7 13 9 17 8 2 6 1 4 16 12 3
For each permutation just draw another 17 random numbers.
This is my first time posting to Stack Exchange, my apologies as I'm certain I will make a few mistakes. I am trying to assess false detections in a dataset.
I have one data frame with "true" detections
truth=
ID Start Stop SNR
1 213466 213468 10.08
2 32238 32240 10.28
3 218934 218936 12.02
4 222774 222776 11.4
5 68137 68139 10.99
And another data frame with a list of times, that represent possible 'real' detections
possible=
ID Times
1 32239.76
2 32241.14
3 68138.72
4 111233.93
5 128395.28
6 146180.31
7 188433.35
8 198714.7
I am trying to see if the values in my 'possible' data frame lies between the start and stop values. If so I'd like to create a third column in possible called "between" and a column in the "truth" data frame called "match. For every value from possible that falls between I'd like a 1, otherwise a 0. For all of the rows in "truth" that find a match I'd like a 1, otherwise a 0.
Neither ID, not SNR are important. I'm not looking to match on ID. Instead I wand to run through the data frame entirely. Output should look something like:
ID Times Between
1 32239.76 0
2 32241.14 1
3 68138.72 0
4 111233.93 0
5 128395.28 0
6 146180.31 1
7 188433.35 0
8 198714.7 0
Alternatively, knowing if any of my 'possible' time values fall within 2 seconds of start or end times would also do the trick (also with 1/0 outputs)
(Thanks for the feedback on the original post)
Thanks in advance for your patience with me as I navigate this system.
I think this can be conceptulised as a rolling join in data.table. Take this simplified example:
truth
# id start stop
#1: 1 1 5
#2: 2 7 10
#3: 3 12 15
#4: 4 17 20
#5: 5 22 26
possible
# id times
#1: 1 3
#2: 2 11
#3: 3 13
#4: 4 28
setDT(truth)
setDT(possible)
melt(truth, measure.vars=c("start","stop"), value.name="times")[
possible, on="times", roll=TRUE
][, .(id=i.id, truthid=id, times, status=factor(variable, labels=c("in","out")))]
# id truthid times status
#1: 1 1 3 in
#2: 2 2 11 out
#3: 3 3 13 in
#4: 4 5 28 out
The source datasets were:
truth <- read.table(text="id start stop
1 1 5
2 7 10
3 12 15
4 17 20
5 22 26", header=TRUE)
possible <- read.table(text="id times
1 3
2 11
3 13
4 28", header=TRUE)
I'll post a solution that I'm pretty sure works like you want it to in order to get you started. Maybe someone else can post a more efficient answer.
Anyway, first I needed to generate some example data - next time please provide this from your own data set in your post using the function dput(head(truth, n = 25)) and dput(head(possible, n = 25)). I used:
#generate random test data
set.seed(7)
truth <- data.frame(c(1:100),
c(sample(5:20, size = 100, replace = T)),
c(sample(21:50, size = 100, replace = T)))
possible <- data.frame(c(sample(1:15, size = 15, replace = F)))
colnames(possible) <- "Times"
After getting sample data to work with; the following solution provides what I believe you are asking for. This should scale directly to your own dataset as it seems to be laid out. Respond below if the comments are unclear.
#need the %between% operator
library(data.table)
#initialize vectors - 0 or false by default
truth.match <- c(rep(0, times = nrow(truth)))
possible.between <- c(rep(0, times = nrow(possible)))
#iterate through 'possible' dataframe
for (i in 1:nrow(possible)){
#get boolean vector to show if any of the 'truth' rows are a 'match'
match.vec <- apply(truth[, 2:3],
MARGIN = 1,
FUN = function(x) {possible$Times[i] %between% x})
#if any are true then update the match and between vectors
if(any(match.vec)){
truth.match[match.vec] <- 1
possible.between[i] <- 1
}
}
#i think this should be called anyMatch for clarity
truth$anyMatch <- truth.match
#similarly; betweenAny
possible$betweenAny <- possible.between
I have two data.frames, one with genotype counts and one with a number that I need to normalize my counts from the first dataset.
countsdata=data.frame(genotype1=rep(c(10,20,30,40),each=1),
genotype2=rep(c(100,200,300,400),each=1),
genotype3=rep(c(40,50,60,70),each=1),
genotype4=rep(c(40,50,60,70),each=1)
)
coldata = data.frame(Group =c('genotype1', 'genotype2', 'genotype3', 'genotype4'),
Treatment = rep(c("control","treated"),each = 2),
Norm=rep(c(1,2,5,5)))
I made sure my variables don't have factors
factorsCharacter <- function(d) modifyList(d, lapply(d[, sapply(d, is.factor)],
as.character))
coldata=factorsCharacter(coldata)
Then I see that lapply loops through my counts, one column at the time and through my coldata that contains the normalization value (Norm). All is looking good, until I combined the two action in the same step
> lapply(coldata['Group'],function(group_i){group_i})
$Group
[1] "genotype1" "genotype2" "genotype3" "genotype4"
> lapply(coldata['Group'],function(group_i){countsdata[,group_i]})
$Group
genotype1 genotype2 genotype3 genotype4
1 10 100 40 40
2 20 200 50 50
3 30 300 60 60
4 40 400 70 70
> lapply(coldata['Group'],function(group_i){as.integer(coldata[coldata$Group==group_i,'Norm'])})
$Group
[1] 1 2 5 5
> lapply(coldata['Group'],function(group_i){
+ countsdata[,group_i]/as.integer(coldata[coldata$Group==group_i,'Norm'])
+ })
$Group
genotype1 genotype2 genotype3 genotype4
1 10 100 40 40
2 10 100 25 25
3 6 60 12 12
4 8 80 14 14
Here the result is not what I was expecting (dividing each column by its normalization number). After further inspection I noticed it's normalizing by rows, in other words it's normalizing across different columns, which shouldn't be the case as I am looping through one column at the time. I am probably missing a basic concept but looking through other SO posts didn't find anything I could use. My goal is to fix the code to make the right calculation but I also would like to understand why this code above is not working. Thanks so much.
The problem is in using [ and not [[. So, instead of looping through each of the elements in 'Group' column, we have a list of length 1 with all the elements. So, either use coldata[, 'Group'] or coldata[['Group']] or coldata$Group for looping.
countsdataNew <- countsdata
countsdataNew[] <- lapply(coldata[['Group']],function(group_i)
countsdata[,group_i]/coldata$Norm[coldata$Group==group_i])
countsdataNew
# genotype1 genotype2 genotype3 genotype4
#1 10 50 8 8
#2 20 100 10 10
#3 30 150 12 12
#4 40 200 14 14
If the column name in 'countsdata' and 'Group' column from 'countsdata' are in the same order, we can do this easily with Map
Map(`/`, countsdata, coldata$Norm)
Or just replicate the 'Norm' and do a simple division
countsdata/coldata$Norm[col(countsdata)]
Or with sweep
sweep(countsdata, 2, coldata$Norm, "/")
I always get angry at my R code when I have to process dataframes, i.e. filtering out certain rows. The code gets very illegible as I tend to choose meaningful, but long, names for my objects. An example:
all.mutations.extra.large.name <- read.delim(filename)
head(all.mutations.extra.large.name)
id gene pos aa consequence V
ENSG00000105732 ZN574_HUMAN 81 x/N missense_variant 3
ENSG00000125879 OTOR_HUMAN 7 V/3 missense_variant 2
ENSG00000129194 SOX15_HUMAN 20 N/T missense_variant 3
ENSG00000099204 ABLM1_HUMAN 33 H/R missense_variant 2
ENSG00000103335 PIEZ1_HUMAN 11 Q/R missense_variant 3
ENSG00000171533 MAP6_HUMAN 39 A/G missense_variant 3
all.mutations.extra.large.name <- all.mutations.extra.large.name[which(all.mutations.extra.large.name$gene == ZN574_HUMAN)]
So in order to kick out all other lines in which I am not interested I need to reference 3 times the object all.mutations.extra.large.name. And reating this kind of step for different columns makes the code really difficult to understand.
Therefore my question: Is there a way to filter out rows by a criterion without referencing the object 3 times. Something like this would be beautiful: myobj[,gene=="ZN574_HUMAN"]
You can use subset for that:
subset(all.mutations.extra.large.name, gene == "ZN574_HUMAN")
Several options:
all.mutations.extra.large.name <- data.frame(a=1:5, b=2:6)
within(all.mutations.extra.large.name, a[a < 3] <- 0)
a b
1 0 2
2 0 3
3 3 4
4 4 5
5 5 6
transform(all.mutations.extra.large.name, b = b^2)
a b
1 1 4
2 2 9
3 3 16
4 4 25
5 5 36
Also check ?attach if you would like to avoid repetitive typing like all.mutations.extra.large.name$foo.
I am trying to use the loop over the column names of the existing dataframe and then create new columns based on one of the old column.Here is my sample data:
sample<-list(c(10,12,17,7,9,10),c(NA,NA,NA,10,12,13),c(1,1,1,0,0,0))
sample<-as.data.frame(sample)
colnames(sample)<-c("x1","x2","D")
>sample
x1 x2 D
10 NA 1
12 NA 1
17 NA 1
7 10 0
9 20 0
10 13 0
Now, I am trying to use for loop to generate two variables x1.imp and x2.imp that have values related to D=0 when D=1 and values related to D=1 when D=0(Here I actually don't need for loop but for my original dataset with large cols (variables), I really need the loop) based on the following condition:
for (i in names(sample[,1:2])){
sample$i.imp<-with (sample, ifelse (D==1, i[D==0],i[D==1]))
i=i+1
return(sample)
}
Error in i + 1 : non-numeric argument to binary operator
However, the following works, but it doesn't give the names of new cols as imp.x2 and imp.x3
for(i in sample[,1:2]){
impt.i<-with(sample,ifelse(D==1,i[D==0],i[D==1]))
i=i+1
print(as.data.frame(impt.i))
}
impt.i
1 7
2 9
3 10
4 10
5 12
6 17
impt.i
1 10
2 12
3 13
4 NA
5 NA
6 NA
Note that I already know the solution without loop [here]. I want with loop.
Expected output:
x1 x2 D x1.impt x2.imp
10 NA 1 7 10
12 NA 1 9 20
17 NA 1 10 13
7 10 0 10 NA
9 20 0 12 NA
10 13 0 17 NA
I would greatly appreciate your valuable input in this regard.
This is nuts, but since you are asking for it... Your code with minimum changes would be:
for (i in colnames(sample)[1:2]){
sample[[paste0(i, '.impt')]] <- with(sample, ifelse(D==1, get(i)[D==0],get(i)[D==1]))
}
A few comments:
replaced names(sample[,1:2]) with the more elegant colnames(sample)[1:2]
the $ is for interactive usage. Instead, when programming, i.e. when the column name is to be interpreted, you need to use [ or [[, hence I replaced sample$i.imp with sample[[paste0(i, '.impt')]]
inside with, i[D==0] will not give you x1[D==0] when i is "x1", hence the need to dereference it using get.
you should not name your data.frame sample as it is also the name of a pretty common function
This should work,
test <- sample[,"D"] == 1
for (.name in names(sample)[1:2]){
newvar <- paste(.name, "impt", sep=".")
sample[[newvar]] <- ifelse(test, sample[!test, .name],
sample[test, .name])
}
sample