pythonpandasfloating-pointprecision

How to check if float pandas column contains only integer numbers?

I have a dataframe

df = pd.DataFrame(data=np.arange(10),columns=['v']).astype(float)

How to make sure that the numbers in v are whole numbers? I am very concerned about rounding/truncation/floating point representation errors

Solution

  • Comparison with astype(int)

    Tentatively convert your column to int and test with np.array_equal:

    np.array_equal(df.v, df.v.astype(int))
True

    float.is_integer

    You can use this python function in conjunction with an apply:

    df.v.apply(float.is_integer).all()
True

    Or, using python's all in a generator comprehension, for space efficiency:

    all(x.is_integer() for x in df.v)
True