Is there a concise way to show all rows in pandas for just the current command?

问题

Sometimes I want to show all of the rows in a pandas DataFrame, but only for a single command or code-block.

Of course I can set the "max_rows" display option to a large number, but then I have to repeat the command afterwards in order to revert to my preferred setting. (I like 12 rows max, personally).

pd.options.display.max_rows=1000
myDF
pd.options.display.max_rows=12

That's annoying.

I read in the documentation that I can use the pd.option_context() function to accomplish this if I combine my command with a "with" statement:

with pd.option_context("display.max_rows", 1000): myDF

I couldn't get that to work, (no output is returned). But I think such a solution would still be too much typing for routine incidental usage!

I wish there was some quick pythonic way to override the display options!
Does one exist? Have I overlooked something?

I like how one can alter the # of rows that the .head() function outputs by passing it an argument for the # of rows, but it still must be lower than the "display.max_rows" setting...

I know I could keep the "display.max_rows" setting really high all the time, and then tack a .head(12) function on most of the time, but I think most people would agree on how annoying that would be.

I am indeed aware that one can view all (or most of?) the values in a pandas Series by passing it to a core function such as list(). But that is tricky to do with a DF. Furthermore, it's hard to read when it's not in a tabular format.

Similar to the solution for my first question, I imagine there's probably a way to write my own function (to be placed in a startup script), but I'm not sure the best way to write it.

回答1:

You could write a function that explicitly calls display

E.g., consider this function:

from IPython.display import display

def show_more(df, lines):
    foo = 1
    display(df)
    foo = 2

When I call the function (just tried it):

>> show_more(df, 1000)
... # <- Shows here the DF

then it displays the dataframe, even though the line foo = 2 is executed after. It follows that you can set the options instead of the line foo = 1 and unset it in the line foo = 2. In fact, you can just use the context manager from your question, probably.

回答2:

This won't display anything because it does not return anything:

with pd.option_context("display.max_rows", 1000): myDF

Calling display inside the with block should work:

with pd.option_context("display.max_rows", 1000):
    display(myDF)

回答3:

This seems to work as expected in pandas 0.22.0 (importing only pandas, without IPython):

import pandas as pd    
with pd.option_context("display.max_rows", 1000): myDF

Presumably that's because the default behaviour is to return the repr of myDF. IDEs may well override this.

If that's too much typing, then a straightforward print to the terminal also works when wrapped in a function:

from __future__ import print_statement  # for python2

def show_rows(df, nrows=1000):
    with pd.option_context("display.max_rows", nrows): print(df)

Edit: calling show_rows(df) will by default print the first 1000 rows of your dataframe df to standard output.

回答4:

You can use following helper function to print full data frame and set max_rows to normal after printing.

def print_full(df):
    import pandas as pd
    pd.set_option('display.max_rows', len(df))
    print(df)
    pd.reset_option('display.max_rows')

回答5:

One-liner to force display all rows (in jupyter):

import IPython.display

IPython.display.HTML(df.to_html())

来源：https://stackoverflow.com/questions/30876193/is-there-a-concise-way-to-show-all-rows-in-pandas-for-just-the-current-command

标签

python

pandas