擅长:python、mysql、java
<pre><code>import numpy as np
import pandas as pd
df = pd.DataFrame(data = np.arange(8).reshape(4,2), columns=['name', 'value'])
</code></pre>
<p>结果:</p>
<pre><code>>>> df
name value
0 0 1
1 2 3
2 4 5
3 6 7
>>> any(df.name == 4)
True
>>> any(df.name == 5)
False
</code></pre>
<p>第二部分:</p>
<pre><code>my_data = np.arange(8).reshape(4,2)
my_data[0,0] = 4
df = pd.DataFrame(data = my_data, columns=['name', 'value'])
</code></pre>
<p>结果:</p>
<pre><code>>>> df.loc[df.name == 4]
name value
0 4 1
2 4 5
</code></pre>
<p>更新:</p>
<pre><code>my_data = np.arange(8).reshape(4,2)
my_data[0,0] = 4
df = pd.DataFrame(data = my_data, index=['a', 'b', 'c', 'd'], columns=['name', 'value'])
</code></pre>
<p>结果:</p>
<pre><code>>>> df.loc[df.name == 4] # gives relevant rows
name value
a 4 1
c 4 5
>>> df.loc[df.name == 4].index # give "row names" of relevant rows
Index([u'a', u'c'], dtype=object)
</code></pre>