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

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