Removing display of row names from data frame

问题:

I am creating a dataframe using this code:

df <- data.frame(dbGetQuery(con, paste('select * from test')))

Which results in this:

    UID      BuildingCode   AccessTime
1   123456   BUILD-1        2014-06-16 07:00:00
2   364952   BUILD-2        2014-06-15 08:00:00
3    95865   BUILD-1        2014-06-06 09:50:00

I am then trying to remove the row names (1, 2, 3, etc) as suggested here by using this code:

rownames(df) <- NULL

But then when I print out df it still displays the row names. Is there a way to not include the row names when creating the data frame? I found a suggestion about row.name = FALSE but when I tried it I just got errors (I might have placed it in the wrong place).

EDIT: What I want to do is convert the dateframe to a HTML table and I don't want the row name to be present in the table.

回答1:

You have successfully removed the rownames. The print.data.frame method just shows the row numbers if no rownames are present.

df1 <- data.frame(values = rnorm(3), group = letters[1:3],
                  row.names = paste0("RowName", 1:3))
print(df1)
#            values group
#RowName1 -1.469809     a
#RowName2 -1.164943     b
#RowName3  0.899430     c

rownames(df1) <- NULL
print(df1)
#     values group
#1 -1.469809     a
#2 -1.164943     b
#3  0.899430     c

You can suppress printing the rownames and numbers in print.data.frame with the argument row.names.

print(df2, row.names = FALSE)
#     values group
# -1.4345829     d
#  0.2182768     e
# -0.2855440     f

Edit: As written in the comments, you want to convert this to HTML. From the xtable and print.xtable docs you can see that the argument include.rownames will do the trick.

library("xtable")
print(xtable(df1), type="html", include.rownames = FALSE)
#<!-- html table generated in R 3.1.0 by xtable 1.7-3 package -->
#<!-- Thu Jun 26 12:50:17 2014 -->
#<TABLE border=1>
#<TR> <TH> values </TH> <TH> group </TH>  </TR>
#<TR> <TD align="right"> -0.34 </TD> <TD> a </TD> </TR>
#<TR> <TD align="right"> -1.04 </TD> <TD> b </TD> </TR>
#<TR> <TD align="right"> -0.48 </TD> <TD> c </TD> </TR>
#</TABLE>

回答2:

Yes I know it is over half a year later and a tad late, BUT

row.names(df) <- NULL

does work. For me at least :-)

And if you have important information in row.names like dates for example, what I do is just :

df$Dates <- as.Date(row.names(df))

This will add a new column on the end but if you want it at the beginning of your data frame

df <- df[,c(7,1,2,3,4,5,6,...)]

Hope this helps those from Google :)