CODEWITHSUNDEEP
rdo.call
xirururu
xirururu

Reputation: 5508

How can I use do.call calculate the mean of a data.frame in R?

I know, I can use sapply and colMeans to rowMeans for the mean value of a data.frame. But now, I am learning do.call and want to try it with do.call().

I tried different way to do that, but I can't get the result what I want.

For example, I want get the result as the same from sapply:

myIris <- iris[1:4]
head(myIris)
sapply(myIris, mean)

#Here is the result what I want
#Sepal.Length  Sepal.Width Petal.Length  Petal.Width 
#5.843333     3.057333     3.758000     1.199333

So I tried this with do.call() with different way, all told me wrong!

do.call("mean", myIris) # Wrong!
do.call("mean", x=myIris) # Wrong!
do.call("mean", list(x=myIris)) # Wrong!
....

Do you know how to do it with the do.call?

Upvotes: 2

Views: 402

Answers (2)

akrun
akrun

Reputation: 887223

If we need both rowMeans and colMeans to be run using lapply/sapply

lapply(c('colMeans', 'rowMeans'), function(x) get(x)(myIris))
#[[1]]
#Sepal.Length  Sepal.Width Petal.Length  Petal.Width 
#    5.843333     3.057333     3.758000     1.199333 

#[[2]]
#  [1] 2.550 2.375 2.350 2.350 2.550 2.850 2.425 2.525 2.225 2.400 2.700 2.500
# [13] 2.325 2.125 2.800 3.000 2.750 2.575 2.875 2.675 2.675 2.675 2.350 2.650
# [25] 2.575 2.450 2.600 2.600 2.550 2.425 2.425 2.675 2.725 2.825 2.425 2.400
# [37] 2.625 2.500 2.225 2.550 2.525 2.100 2.275 2.675 2.800 2.375 2.675 2.350
# [49] 2.675 2.475 4.075 3.900 4.100 3.275 3.850 3.575 3.975 2.900 3.850 3.300
# [61] 2.875 3.650 3.300 3.775 3.350 3.900 3.650 3.400 3.600 3.275 3.925 3.550
# [73] 3.800 3.700 3.725 3.850 3.950 4.100 3.725 3.200 3.200 3.150 3.400 3.850
# [85] 3.600 3.875 4.000 3.575 3.500 3.325 3.425 3.775 3.400 2.900 3.450 3.525
# [97] 3.525 3.675 2.925 3.475 4.525 3.875 4.525 4.150 4.375 4.825 3.400 4.575
#[109] 4.200 4.850 4.200 4.075 4.350 3.800 4.025 4.300 4.200 5.100 4.875 3.675
#[121] 4.525 3.825 4.800 3.925 4.450 4.550 3.900 3.950 4.225 4.400 4.550 5.025
#[133] 4.250 3.925 3.925 4.775 4.425 4.200 3.900 4.375 4.450 4.350 3.875 4.550
#[145] 4.550 4.300 3.925 4.175 4.325 3.950

Or use

 lapply(list(colMeans, rowMeans), do.call, list(myIris))

Upvotes: 2

Ronak Shah
Ronak Shah

Reputation: 389047

Using colMeans instead of mean would give you the desired result

do.call("colMeans", list(myIris))

# Sepal.Length  Sepal.Width Petal.Length  Petal.Width 
#    5.843333     3.057333     3.758000     1.199333

Upvotes: 4

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