Find integer row-index from pandas index
<p>The following code find index where df['A'] == 1</p>

<pre><code>import pandas as pd
import numpy as np
import random

index = range(10)
random.shuffle(index)
df = pd.DataFrame(np.zeros((10,1)).astype(int), columns = ['A'], index = index)

df.A.iloc[3:6] = 1
df.A.iloc[6:] = 2

print df

print df.loc[df['A'] == 1].index.tolist()
</code></pre>

<p>It returns pandas index correctly. How do I get the integer index ([3,4,5]) instead using pandas API?</p>

<pre><code>   A
8  0
4  0
6  0
3  1
7  1
1  1
5  2
0  2
2  2
9  2
[3, 7, 1]
</code></pre>

<p>No need for numpy, you're right. Just pure python with a listcomp:</p>

<p>Just find the indexes where the values are 1</p>

<pre><code>print([i for i,x in enumerate(df['A'].values) if x == 1])
</code></pre>

python pandas dataframe row indices