Pandas - Get first row value of a given column

Question

This seems like a ridiculously easy question... but I'm not seeing the easy answer I was expecting.

So, how do I get the value at an nth row of a given column in Pandas? (I am particularly interested in the first row, but would be interested in a more general practice as well).

For example, let's say I want to pull the 1.2 value in Btime as a variable.

Whats the right way to do this?

df_test =

  ATime   X   Y   Z   Btime  C   D   E

0    1.2  2  15   2    1.2  12  25  12

1    1.4  3  12   1    1.3  13  22  11

2    1.5  1  10   6    1.4  11  20  16

3    1.6  2   9  10    1.7  12  29  12

4    1.9  1   1   9    1.9  11  21  19

5    2.0  0   0   0    2.0   8  10  11

6    2.4  0   0   0    2.4  10  12  15

Answer 1

 Use iloc to select the ith row,

In [31]: df_test.iloc[0]

Out[31]: 

ATime     1.2

X         2.0

Y        15.0

Z         2.0

Btime     1.2

C        12.0

D        25.0

E        12.0

Name: 0, dtype: float64

And for selecting the ith value in the Btime column you can use:

In [30]: df_test['Btime'].iloc[0]

Out[30]: 1.2