Check if values in pandas dataframe column is integer and write it to a list if not

Question

I have a pandas dataframe with a column which could have integers, float, string etc. I would like to iterate over all the rows and check if each value is integer and if not, I would like to create a list with error values (values that are not integer)

I have tried isnumeric(), but couldnt iterate over each row and write errors to output. I tried using iterrows() but it converts all values to float.

ID     Field1
1      1.15
2      2
3      1
4      25
5      and

Expected Result:

[1.15,"and"]

Could you show what df['Field1'].tolist() looks like for this DataFrame please? — cs95
– cs95, Commented May 21, 2019 at 17:23
I ask because the solution depends on whether the data is all strings or the column has mixed dtypes. — cs95
– cs95, Commented May 21, 2019 at 17:27

cs95 · Accepted Answer · 2019-05-21 17:47:11Z

15

If "Field1" is a column of strings, use str.isdigit (returns True for integers only) and negate:

df.loc[~df['Field1'].str.isdigit(), 'Field1'].tolist()
# ['1.15', 'and']

Alternatively, if the column contains mixed types, use

df.loc[~df['Field1'].astype(str).str.isdigit(), 'Field1'].tolist()
# [1.15, 'and']

edited May 21, 2019 at 17:47

answered May 21, 2019 at 17:30

cs95

406k106 gold badges744 silver badges797 bronze badges

Sign up to request clarification or add additional context in comments.

9 Comments

prosti Over a year ago

Works really well.

cs95 Over a year ago

@prosti Thank you. I felt it was worth confirming the dtype of OP's data so we could find them a working solution quickly :)

prosti Over a year ago

But it must be string = dtype('object') for that column since we deal with strings in that column. ;) else I am unaware something else may came in like dtype complex.

cs95 Over a year ago

@prosti object is a broad sweeping generalisation for anything that isn't scalar. This includes strings as well as mixed types. If they are strings, you can directly find a solution. Otherwise you would need to convert them to string first to have the string methods actually return useful results on them.

Padfoot123 Over a year ago

Thanks Guys.. I am getting error - bad operand type for unary ~: 'float'

|

Collectives™ on Stack Overflow

Check if values in pandas dataframe column is integer and write it to a list if not

1 Answer 1

9 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

9 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related