Apply / Lambda

vectorized_valc.py

import numpy as np
import pandas as pd

samples = 100000
df = pd.DataFrame(
    {
        'col1':np.random.randint(2,100,samples),
        'col2':np.random.randint(2,100,samples),
        'col3':np.random.rand(samples)
    }
)
df.col3 = df.col3.apply(lambda x: str(x).replace('.',','))

%%timeit
results = []
for _, row in df.iterrows():
    results.append(float(row.col3.replace(',','.')))
    
    
%%timeit
results = df.col3.apply(lambda x: x.replace(',','.')).values