spread error: Each row of output must be identified by a unique combination of keys.

[Jan.R]

Hello all,

I have a data frame (df) that looks like this:

   month year             label         color    value
1      1 2012      0. Not labelled     #ffffff     1
2      1 2012      0. Not labelled     #ffffff     1
3      2 2012      0. Wet              #ffffff     1
4      3 2012      0. Wet              #ffffff     1
5      4 2012      0. average          #ffffff     1
6      5 2012      0. average          #ffffff     1
...
94     7 2015      4. Dry              #d7191c     1
95     6 2014      4. Dry              #d7191c     1
96     8 2018      4. Dry              #d7191c     1

With the following line I'm trying to spread my dataframe by the labels:

df <- spread(df, label, color)

But I get the following Error:

Error: Each row of output must be identified by a unique combination of keys.
Keys are shared for 2 rows:
* 1, 2

I dont understand the Error, and thus have no idea on how to fix it.
Could anyone explain me the Error and explain me how to fix it?
Thanks in advance

[martin.R]

The error message tells you the problem. Rows 1 and 2 are the same, so spread() cannot work.

Check whether one of the rows should be deleted or else whether the data is correct.

You could use pivot_wider(), but I doubt you want list columns as output:

df <- pivot_wider(df, names_from = label, values_from = color)

[Jan.R]

Thanks a lot, removing the first row solved the problem