??? .head() displays 5 rows without mentioning it
<p><em>I'm confused here. 
Below is command to view the dataset shape:</em></p>

<pre><code>   In[] df_faa_dataset.shape
   Out[] (83, 42)
</code></pre>

<p><em>Now I want to see first 5 rows and entered command:</em></p>

<pre><code>In[] df_faa_dataset.head()
Out[] (displayed output with 5 rows Ã 42 columns)
</code></pre>

<p><em>How come by default <code>.head()</code> method took 5 rows without mentioning in the bracket?</em> </p>

<p><a href="http://pandas.pydata.org/pandas-docs/stable/generated/pandas.DataFrame.head.html" rel="nofollow">link to official docs</a></p>

<p><a class='doc-link' href="http://stackoverflow.com/documentation/pandas/1751/indexing-and-selecting-data/21739/slice-dataframe-from-beginning-or-end#t=201610180457416242455">link to stackoverflow docs</a></p>

<p><strong><em>copied from documentation</em></strong>  </p>

<blockquote>
<pre><code>DataFrame.head(n=5)
Returns first n rows
</code></pre>
</blockquote>

<p>It is how we establish default parameter values in python.  For the <code>head</code> method, <code>n=5</code> means that the default value is 5 and consequently, if you do not pass a parameter value yourself, then 5 is used.</p>

python pandas dataframe