R: Find matching string then copying row - r

Question

I have a multi-step problem. First step: match text in one string (df1) from one column to another range of columns (df2). There is no order of which columns match and the match could occur anywhere within the range. Once the match is found, copy the df2 row match into df1. Finally, repeat for the entire column.
df1= structure(list(Assay = c("ATG_AR_trans_up","NVS_PXR_cis","BSK_VCAM1_up"), p.value = c(0.01,0.05,0.0001)), .Names = c("Assay", "p.value"),row.names = c(NA, 3L), class = "data.frame")
df1
Assay p.value
ATG_AR_trans_up 0.01
NVS_hPXR 0.065
BSK_VCAM1_up 0.001
df2=structure(list(GeneID = c("AR", "VACM1", "TR", "ER", "PXR"), Assay1= c("ATG_ARE_cis", "BSK_hEDG_VCAM1", "NVS_TR_tran", "ATG_ER_UP", "NVS_PXRE_UP"), Assay2= c("ATG_AR_trans_up", "BSK_BE3K_VCAM1", "NA", "ATG_ERE_cis", "ATG_PXRE_cis"), Assay3= c("NVS_AR_trans", "BSK_VCAM1_UP", "NA", "NVS_ERa_CIS", "NVS_PXR_cis"), Assay4= c("Tox21_AR_ARE","NA", "NA", "Tox21_ERaERb_lig", "NA")), .Names = c("GeneID", "Assay1", "Assay2", "Assay3", "Assay4"),row.names = c(NA, 5L), class = "data.frame")
df2
GeneID Assay1 Assay 2 Assay3
AR ATG_ARE_cis NVS_hAR ATG_AR_trans_up
VACM1 BSK_hEGF_CAM1 BSK_VCAM1_up BSK_VCAM1_down
TR NVS_TR_tran NA NA
ER ATG_ER_UP ATG_ERE_cis NVS_ERa_CIS
PXR ATG_PXR_down ATG_PXRE_cis NVS_hPXR
Essentially becomes
df
Assay p.value GeneID Assay1 Assay2 Assay3
ATG_AR_trans_up 0.01 AR ATG_ARE_cis NVS_hAR ATG_AR_trans_up
NVS_hPXR 0.065 PXR ATG_PXR_down ATG_PXRE_cis NVS_hPXR
BSK_VCAM1_up 0.001 VCAM1 BSK_hEGF_CAM1 BSK_VCAM1_up BSK_VCAM1_down
For brevity I shortened the df substantially, but it is around 88 Assays and 4,000 some rows to go through for just one match (there are about 30). So a my initial instinct is to loop, but I was told grep might be a helpful package (even though it is not for R 3.2.2). Any help would be appreciated though.

Answer 1

Since OP was interested in a grep solution, another way to do it would be,
asDF2 <- apply(df2, 1, function(r) do.call(paste, as.list(r)))
do.call(rbind, lapply(1:nrow(df1),
function(i){
matchIX <- grepl(df1$Assay[i], asDF2, ignore.case=T)
if(any(matchIX))
cbind(df1[i, ], df2[matchIX, ])
}))
The first line creates a character vector with concatenated row assay names of df2. The second line loops through df1 and finds match in asDF2 using grepl
Or equivalently,
do.call(rbind, lapply(1:nrow(df1),
function(i){
matchIX <- grepl(df1$Assay[i],
data.frame(t(df2), stringsAsFactors=F),
ignore.case=T)
if(any(matchIX))
cbind(df1[i, ], df2[matchIX, ])
} ))
Note that above variants, can match multiple rows in df2 to df1.
NOTE
To test I added new rows to original data frames as
df1 <- rbind(df1, data.frame(Assay="NoMatch", p.value=.2))
df2 <- rbind(df2,
data.frame(GeneID="My", Assay1="NVS_PXR_cis", Assay2="NA", Assay3="NA", Assay4="NA"))

Answer 2

This can be easily done with reshaping. I put all the assays into all caps because that was messing up the matching.
library(dplyr)
library(tidyr)
library(stringi)
df2_ID = df %>% mutate(new_ID = 1:n() )
result =
df2_ID %>%
select(new_ID, Assay1:Assay85) %>%
gather(assay_number, Assay, Assay1:Assay85) %>%
mutate(Assay =
Assay %>%
iconv(to = "ASCII") %>%
stri_trans_toupper) %>%
inner_join(df1 %>%
mutate(Assay =
Assay %>%
iconv(to = "ASCII") %>%
stri_trans_toupper)) %>%
inner_join(df2_ID)

Answer 3

Since you're new to R, I think you are right that the most intuitive way to do this is with a for-loop. This is not the most concise or most efficient way to do this, but it should be clear what's going on.
# Creating example data
df1 <- as.data.frame(matrix(data=c("aa", "bb", "ee", .9, .5, .7), nrow=3))
names(df1) <- c("assay", "p")
df2 <- as.data.frame(matrix(data=c("G1", "G2", "aa", "dd", "bb", "ee", "cc", "ff"), nrow=2))
names(df2) <- c("GeneID", "assay1", "assay2", "assay3")
# Building a dataframe to store output
df3 <- as.data.frame(matrix(data=NA, nrow=dim(df1)[1], ncol=dim(df2)[2]))
names(df3) <- names(df2)
# Populating dataframe with output
for(i in 1:dim(df1)[1]){
index <- which(df2==as.character(df1$assay[i]), arr.ind = TRUE)[1]
for(j in 1:dim(df3)[2]){
df3[i,j] <- as.character(df2[index,j])
}
}
df <- cbind(df1, df3)

Answer 4

Edit after clarification from user:
I just created a triple for loop to check your values. Basically what it does is it looks for a match. It does this by looping through all columns and all the values from that column.
However my code is not perfect yet (also a beginner in R) and I just wanted to post it so that maybe we can work something out together :).
So I first convert your data to a data.frame. After that I create an empty output which I later fill per match found.
The improvements in this method would be that with this solution the function append will also append the column names which will result in multiple useless column names.
df3 <- as.data.frame(df1)
df4 <- as.data.frame(df2)
output <- data.frame()
for(j in 1:nrow(df3)) {
match <- FALSE
for(i in 2:(ncol(df4))) {
for(p in 1:nrow(df4)) {
if((df3[j, 1] == df4[p, i]) && (match == FALSE)) {
output <- append(output, c(df3[j, ], df4[j, ]))
match <- TRUE
}
}
}
}

Answer 5

Assuming, you don't have any repeated entry corresponding to the entry in df1. Following is the solution for your problem:
assay <-as.matrix(df1[,1])
m1 <- as.numeric(sapply(assay, function(x){grep(x,df2[,2], ignore.case = T)}, simplify = FALSE))
m2 <- as.numeric(sapply(assay, function(x){grep(x,df2[,3], ignore.case = T)}, simplify = FALSE))
m3 <- as.numeric(sapply(assay, function(x){grep(x,df2[,4], ignore.case = T)}, simplify = FALSE))
m4 <- as.numeric(sapply(assay, function(x){grep(x,df2[,5], ignore.case = T)}, simplify = FALSE))
m1[is.na(m1)] <- 0
m2[is.na(m2)] <- 0
m3[is.na(m3)] <- 0
m4[is.na(m4)] <- 0
m0 <- (m1+m2+m3+m4)
df <- NULL
for(i in 1:nrow(df1){
df3 = cbind(df1[i,],df2[m0[i],])
df = rbind(df,df3)
}
Edit: Generalization
Since you have more than 80 rows, you can generalize it as under:
assay <-as.matrix(df1[,1])
# Storing Assay column in a list
m <- vector('list',ncol(df2[, 2:ncol(df2)]))
for(i in 1:length(m)){
m[[i]] <- as.numeric(sapply(assay, function(x){grep(x,df2[,(i+1)], ignore.case = T)}, simplify = FALSE))
}
# Getting row subscript for df2
m1 <- as.data.frame(m)
m1[is.na(m1)] <- 0
m2 <- rowSums(m1)
df <- NULL
for(i in 1:nrow(df1)){
df3 = cbind(df1[i,],df2[m2[i],])
df = rbind(df,df3)
}