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python - Pandas adding scalar value to numeric column?

Given a dataframe like this

   ImageId | Width | Height | lb0 | x0 | y0 | lb1 | x1 | y1 | lb2 | x2 | y2
0  abc     | 200   | 500    | ijk | 115| 8  | zyx | 15 | 16 | www | 23 | 42
1  def     | 300   | 800    | ijk | 91 | 23 | zyx | 16 | 15 | www | 8  | 4
2  ghi     | 700   | 400    | ijk | 230| 16 | zyx | 17 | 24 | www | 43 | 109
3  jkl     | 500   | 100    | ijk | 46 | 23 |     |    |    |     |    |
...

When I try to add to a column with

df['x0'] = df['x0'] + 1

I now get column x0 as follows:

151
127
266
82

Question:

  • How do I add a scalar value to a whole column in Pandas?
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You probably don't have an int dtype. Doing

df['x0'] = df['x0'].astype(int) + 1

should work


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