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Why R order files as 1 10 100 not 1 2 3 ?

2 messages · sam84, R. Michael Weylandt

sam84
# 
The code given below worked well. However, the problem is that when I typed  
dir1 to see the results I found that R order the files as:
[1] "data1.flt"   "data10.flt"  "data100.flt" "data101.flt"
  [5] "data102.flt" "data103.flt" "data104.flt" "data105.flt"
  [9] "data106.flt" "data107.flt" "data108.flt" "data109.flt"
 [13] "data11.flt"  "data110.flt" "data111.flt" "data112.flt"
 [17] "data113.flt" "data114.flt" "data115.flt" "data116.flt"
.
.
to
.
.
[357] "data91.flt"  "data92.flt"  "data93.flt"  "data94.flt"
[361] "data95.flt"  "data96.flt"  "data97.flt"  "data98.flt"
[365] "data99.flt"


which will lead to wrong results.
How to tell R to start reading from 1 to 365 in order.
something like :

[1] "data1.flt"   "data2.flt"  "data3.flt" "data4.flt"
not like:

[1] "data1.flt"   "data10.flt"  "data100.flt" "data101.flt"
Here is the code:
dir1<- list.files("C:\\Users\\Amin\\Desktop\\2001", "*.flt", full.names =
TRUE)
results<- list()
for (.files in seq_along(dir1)){
      file2 <- readBin(dir2[.files], double(), size = 4, n = w * 67420,
signed = TRUE)
    results[[length(results) + 1L]]<- file1[file1 != -9999]*10}
for (i in seq_along(results)){
    fileName <- sprintf("C:\\Users\\aalyaari\\Desktop\\New folder
(2)\\NewFile%03d.bin", i)
    writeBin(as.integer(results[[i]]), fileName, size = 2)} 

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R. Michael Weylandt
# 
It's because those are character strings and they are sorted lexically
(i.e., alphabetically). I think you probably can get what you prefer
by using the mixedsort/mixedorder functions of the gtools package.

Take a look at this

x <- paste0("data",1:100, ".fit")
order(x)

sort(x)

library(gtools)
mixedorder(x)

mixedsort(x)

Best,
Michael
On Mon, May 28, 2012 at 10:06 AM, sam84 <samiyemny at yahoo.co.uk> wrote: