Managing absence of results when selecting a variable in a dataframe

Question

When my dataset contains all the variables, I can create a subset by selecting just the variables I need. But If one if missing I got Nothing. How can I manage such an error ?

df = df_ori[[ 'FINAL', 'DUE', 'ID', 'NAME', 'BUSINESS 1', 'TAX 2', 'COUNT' ]] This works and df exists when all the variables in df_ori are there. But then I want to go further by managing a potential error if one variable is missing.

if df.empty: print("Field(s) mendatory missing") #doesn't work if in df_ori dataframe the field 'ID' is missing for instance. I cannot enter in this "IF"

No error but there is no dataframe df generated or "Field(s) mendatory missing" doesn't appear

Welcome to stack overflow! Unfortunately your question is not entirely clear. Please take a look at [How to make good pandas examples](https://stackoverflow.com/questions/20109391/how-to-make-good-reproducible-pandas-examples) and edit your question to include a [mcve], including sample input, sample output, and code for what you've tried so far. This will help us to help you better — G. Anderson, Aug 26 '19 at 16:42

score 0 · Accepted Answer · answered Aug 26 '19 at 18:20

IIUC, use reindex with axis=1:

df = pd.DataFrame(np.random.randint(0,10,(5,5)), columns=[*'ABCDE'])

where,

df[['A','B','C','Z']]

generates KeyError: "['Z'] not in index"

Use,

df.reindex(['A','B','C','Z'], axis=1)

Output:

   A  B  C   Z
0  9  9  8 NaN
1  2  6  7 NaN
2  6  6  6 NaN
3  3  7  9 NaN
4  7  2  2 NaN

Managing absence of results when selecting a variable in a dataframe

1 Answers1