How to slice a Pandas Data Frame by position?
PythonPandasDataframeSlicePython Problem Overview
I have a Pandas Data Frame object that has 1000 rows and 10 columns. I would simply like to slice the Data Frame and take the first 10 rows. How can I do this? I've been trying to use this:
>>> df.shape
(1000,10)
>>> my_slice = df.ix[10,:]
>>> my_slice.shape
(10,)
Shouldn't my_slice be the first ten rows, ie. a 10 x 10 Data Frame? How can I get the first ten rows, such that my_slice is a 10x10 Data Frame object? Thanks.
Python Solutions
Solution 1 - Python
df2 = df.head(10)
should do the trick
Solution 2 - Python
You can also do as a convenience:
df[:10]
Solution 3 - Python
df.ix[10,:] gives you all the columns from the 10th row. In your case you want everything up to the 10th row which is df.ix[:9,:]. Note that the right end of the slice range is inclusive: http://pandas.sourceforge.net/gotchas.html#endpoints-are-inclusive
Solution 4 - Python
I can see at least three options:
Option 1
df[:10]
Option 2
Using head
df.head(10)
> For negative values of n, this function returns all rows except the
> last n rows, equivalent to df[:-n] [Source].
Option 3
Using iloc
df.iloc[:10]
Solution 5 - Python
DataFrame[:n] will return first n rows.