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rdataframevectorstatisticsnormal-distribution

How to save 10 different rnorm() in a vector in R?


I need to create a vector, which elements are 10 different normal-distributed random sequences each of length 150. After that for each of these sequences the minimum-, maximum-, mean- and median-value need be calculated. These 4 statistics need be stored in a vector. All 4-element-statistics-vectors shall be stored in a data frame.

i predefined a vector with a length of 10 and was able to create 10 normal distributions with rnorm() and display them using hist(). However I think I failed to save them in the vector.

data <- vector(length = 10)

for(i in 1:10) {
  data[i] <- hist(rnorm(150, 75, 10))
}

Solution

  • You can get your ten samples like this:

    samples <- replicate(10, rnorm(150, 75, 10))
    

    And put their summaries into a data frame like this:

    do.call(rbind, lapply(asplit(samples, 2), function(x) {
      data.frame(min = min(x), max = max(x), mean = mean(x), sd = sd(x))
    }))
    #>         min       max     mean        sd
    #> 1  41.63553 107.15836 74.65818 11.691526
    #> 2  36.27087 103.41606 74.60017 10.580801
    #> 3  53.58147 100.37452 75.35968 10.356784
    #> 4  48.44410  98.91955 75.13158 10.403437
    #> 5  46.69455 102.77960 73.44792 10.692283
    #> 6  52.45185 108.14074 75.42726  9.566448
    #> 7  51.96023  98.63533 75.59220 10.520285
    #> 8  49.03543 102.96443 73.17830 10.615083
    #> 9  45.87507 115.26490 74.54446 10.394427
    #> 10 47.32588  96.58989 75.85079 10.282901
    

    Created on 2022-11-14 with reprex v2.0.2