DataTable sorts number by reading left to right in a column

Question

When using the datatable, the numbers are sorted reading from left to right, instead of right to left. I have it converted to numeric too. Why does it do this? See * numbers It does the same with all columns.

Here's an example: 950 should be the first one, not 96.67

Items   RN.2015 RN.2016 Change.RN
London  30      59      **96.67**
Tokyo   2       21      **950**
Paris   2       21      950
Seoul   2       21      950
New York20      39      95
Orlando 18      35      94.44
Nice    3       31      **933.3**

code in reactive:

library(dplyr)
fileInfo$RN <- as.numeric(as.character(fileInfo$RN))
perChange<-fileInfo %>%
group_by_(input$selCol)  %>%
   summarise( 
      RN.2015 = sum(RN[Year=="2015"]),
      RN.2016 = sum(RN[Year=="2016"])
   )%>%
   mutate(
       Change.RN = delt(RN.2015,RN.2016)
)

function

delt <- function(x,y) {ifelse(is.finite((y-x)/x*100),paste0(formatC((y-x)/x*100),"%"),"")}

data:

Data <- data.frame(
    Items = c("London","Tokyo","Paris","Seoul","New York","Orlando","Nice"),
    RN.2015 = c(30,2,2,2,20,18,3),
    RN.2016 = c(59,21,21,21,39,35,31)
)

[How to make a great R reproducible example?](http://stackoverflow.com/questions/5963269) — zx8754, Sep 16 '16 at 14:17
First, maybe I did, maybe I didn't. Second, edit your post, I maybe upvote or not. In any case, I am trying to understand **your** problem, but at the same time trying to help **others** who might have similar problem, and not just **you** personally. — zx8754, Sep 16 '16 at 14:25
@C8H You might also want to add the corresponding tag in a case like that. Judging by the title, it also needs a DT tag. — Frank, Sep 16 '16 at 18:42
@Frank I thought so too but it's not a `data.table` question at all — C8H10N4O2, Sep 16 '16 at 18:51
@C8H Oh, I meant that you should maybe add the dplyr tag (since you added `library(dplyr)`) and the DT tag. DT is a different package from data.table: http://stackoverflow.com/tags/dt/info The OP might have correctly included it in the title... I'm not sure. — Frank, Sep 16 '16 at 18:55
Possible duplicate of [How to sort a character vector where elements contain letters and numbers in R?](http://stackoverflow.com/questions/17531403/how-to-sort-a-character-vector-where-elements-contain-letters-and-numbers-in-r) — zx8754, Sep 16 '16 at 18:55

C8H10N4O2 · Accepted Answer · 2016-09-16T14:50:47.103

1

In your function delt, paste0 is returning a character vector, so that column is probably getting converted to character.

The sort behavior above is consistent with the way a numeric value could get sorted if it was incorrectly stored as a character vector. 96.6 > 955 > 94, etc.

Use str(data) and ensure that column Change.RN is actually a numeric. If not, use as.numeric to convert.

edited Sep 16 '16 at 14:50

answered Sep 16 '16 at 14:45

C8H10N4O2

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DataTable sorts number by reading left to right in a column

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