Automating chunking of big data in R using a loop -



Automating chunking of big data in R using a loop -

i trying break big dataset chunks. code looks this:

#chunk 1 info <- read.csv("/users/admin/desktop/data/sample.csv", header=t, nrow=1000000) write.csv(data, "/users/admin/desktop/data/data1.csv") #chunk 2 info <- read.csv("/users/admin/desktop/data/sample.csv", header=f, nrow=1000000, skip=1000000) write.csv(data, "/users/admin/desktop/data/data2.csv") #chunk 3 info <- read.csv("/users/admin/desktop/data/sample.csv", header=f, nrow=1000000, skip=2000000) write.csv(data, "/users/admin/desktop/data/data3.csv")

there hundreds of millions of rows in dataset, need create lot of chunks, , automate process. there way loop command each subsequent chunk automatically skips 1,000,000 more rows previous chunk did, , file saves "datan.csv" (n symbolizing subsequent number of previous file)?

what next way? demonstration created info frame 2 columns , 10 lines , read within loop 2 times, each time 5 lines, saving result text file:

f<-"c:/users/mypc/desktop/" for(i in 1:2){ df <- read.table("c:/users/mypc/desktop/df.txt", header=false, nrow=5, skip=5*(i-1)) file <- paste(f,sep="","df",i,".txt") write.table(df,file) }

r chunking

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