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POAlternative to for-loop to fill data.frame by unique rows
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2013-03-06T21:05:12.047
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I am trying to make a script to generate a random set of people with demographic information using R. I want it to generate by rows and not columns so that a function can be based on the outcome of the previous function in the same row. I know this can be done with a for loop (as I did below) but for loops are extremely slow in R. I have read that you can use apply or while to do a loop much more efficiently but I haven't figured out how despite many failed attempts. A sample of the functional code with the loop is below. How would I do that with apply or while? <pre><code>y <- 1980 ## MedianYr d <- 0.1 ## Rate of NA responses AgeFn <- function(y){ Year <- 1900 + as.POSIXlt(Sys.Date())$year RNormYr <- as.integer((rnorm(1)*10+y)) Age <- Year - RNormYr } EduByAge <- function (Age, d) { ifelse(Age < 17, sample(c("Some High School",NA), size=1,prob=c((1-d),d)), ifelse(Age > 16 & Age < 19, sample(c("Some High School", "High School Grad",NA), size=1, prob=c(0.085, 0.604,d)), ifelse(Age > 18 & Age < 21, sample(c("Some High School", "High School Grad", "Associates",NA), size=1,prob=c(0.085, 0.25, 0.354,d)), ifelse(20 > Age & Age < 23, sample(c("Some High School", "High School Grad", "Associates", "Bachelors",NA), size=1,prob=c(0.085, 0.25, 0.075, 0.279,d)), ifelse(Age > 22, sample(c("Some High School", "High School Grad", "Associates", "Bachelors", "Masters", "Professional", "Doctorate",NA),size=1,prob=c(0.085, 0.25, 0.075, 0.176, 0.072, 0.019, 0.012,d)), NA))))) } GenderFn <- function(d){ Gender1 <- sample(c("Male","Female","Trans", NA), 1, replace=TRUE, prob=c(0.49, 0.5, 0.01, d)) return(Gender1) } UserGen <- function(n,s) { set.seed(s) Rows <- function(y,d){ Age <- abs(AgeFn(y)) Gender <- GenderFn(d) Education <- EduByAge(Age,d) c(i, Age, Gender, Education) } df <- data.frame(matrix(NA, ncol = 4, nrow = n)) for(i in (1:n)) { df[i,] <- Rows(y,d) } colnames(df) <- c("ID", "Age", "Gender", "Education") return(df) } </code></pre>
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<r><for-loop><apply>
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Alternative to for-loop to fill data.frame by unique rows
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