Remove a row from a data table in R

Question

I have a data table with 5778 rows and 28 columns. How do I delete ALL of the 1st row. E.g. let's say the data table had 3 rows and 4 columns and looked like this:

Row number tracking_id    3D71    3D72  3D73
    1          xxx         1       1     1
    2          yyy         2       2     2
    3          zzz         3       3     3

I want to create a data table that looks like this:

    Row number tracking_id    3D71    3D72  3D73
    1          yyy             2       2     2
    2          zzz             3       3     3

i.e. I want to delete all of row number 1 and then shift the other rows up.

I have tried datatablename[-c(1)] but this deletes the first column not the first row!

Many thanks for any help!

for data frames, see http://stackoverflow.com/questions/7541610/how-to-delete-the-first-row-of-a-dataframe-in-r — dww, May 18 '16 at 18:22
`[row, column]` for data frames. You obviously don't have a data table — Rich Scriven, May 18 '16 at 18:24
`datatablename[-1, ]` works for both. why not be explicit with what you want, ie, use commas? — rawr, May 18 '16 at 18:25
Yes I meant data frame not data table - sorry. datatablename[-1,] worked. Thank you. — lharrisl, May 18 '16 at 18:36

Jonathan Rhein · Accepted Answer · 2018-04-06T10:51:21.327

9

You can do this via

dataframename = dataframename[-1,]

edited Apr 06 '18 at 10:51

answered May 18 '16 at 18:22

Jonathan Rhein

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This worked - thank you. And yes sorry I meant data frame not data table. – lharrisl May 18 '16 at 18:34

score 1 · Answer 2 · edited May 19 '16 at 06:03

1

It can be easily done with indexing the data.table/data frame as mentioned by @joni. You can also do with

datatablename <- datatablename[2:nrow(datatablename), ]

You can find more interesting stuff about data.table here.

edited May 19 '16 at 06:03

Arun

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answered May 18 '16 at 18:39

Fitzerbirth

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Remove a row from a data table in R

2 Answers2