R - sort() output missing a row

I have A and B as follows: //edit// I was sleepy and confused. These are NOT data frames.

> length(A)
[1] 490
> length(B)
[1] 17730

> str(A)
 num [1:490] 0.0113 -0.0106 0.2308 0.0435 0.2814 ...
> str(B)
 num [1:17730] 0.0118 0.0196 0.0344 0.0207 0.0566 ...

But for some reason when I used sort():

> length(sort(A))
[1] 490
> length(sort(B))
[1] 17729        #should be 17730

I don't know how to produce a reproducible example in this particular case, and I'm stuck on how I should go about troubleshooting this. What should I check?

Answer #1:

Others have pointed out that sort() takes a vector and not a data.frame, but are there any NAs in the vector? The default in sort() is to remove NAs:

v <- c(2, 1, NA)
v
#[1]  2  1 NA

length(sort(v))
#[1] 2
length(sort(v, na.last = T))
#[1] 3

If you want to sort a data.frame you should use order() instead of sort(). order() has the same na.last argument as sort() except the default is TRUE instead of NA:

df <- data.frame(vars = c(2, 1, NA))
df_n <- data.frame(df[order(df$vars),])

nrow(df_n)
#[1] 3
Answered By: matt_k
The answers/resolutions are collected from stackoverflow, are licensed under cc by-sa 2.5 , cc by-sa 3.0 and cc by-sa 4.0 .



# More Articles