How to suppress output in Google Colaboratory cell which executes a command line script (line starts with `!`) via a function

Question

In Google colab I execute command line scripts by place a ! in front of the line and executing the cell.

For example

!pip install adjustText

If I want to prevent output of this cell, I can do this

%%capture
!pip install adjustText

However, I have a situation where I execute the command line scripts via a function, and suppress output for that command line only, without suppressing the output of the cell from which it's being executed

For example

Cell1:

%%capture
def installAdjust():
    !pip install adjustText

Cell2:

for v in range(10):
    print(v)
    installAdjust()

This does not suppress the output from !pip install adjustText. I do not want to suppress the non-command line output from Cell2, so I can Not do this

Cell2:

%%capture
for v in range(10):
    print(v)
    installAdjust()

Also, this doesn't work either

Cell1:

def installAdjust():
   %%capture
    !pip install adjustText

score 35 · Answer 1 · answered Sep 11 '19 at 07:05

35

you can use '%%capture' magic function in a cell(without quotes) to suppress the output of that particular cell whether it uses a command-line code or some python code, magic function is basically a property of jupyter notebooks but since google colab is built over this, it will work there also. eg:

%%capture
!wget https://github.com/09.10-20_47_44.png

answered Sep 11 '19 at 07:05

bhanu pratap

626
7
10

Wow this answer saved my day! – Jinhua Wang Mar 05 '20 at 22:44
Hm, this doesn't work for me, I still get the output printed below the cell. Do I have to reload the notebook or something? – NeStack Nov 03 '21 at 19:04
Not actually, it works for me even without reloading the notebook, What specifically you run? – bhanu pratap Nov 05 '21 at 04:13

score 8 · Accepted Answer · answered Jun 23 '19 at 20:53

Use capture_output from python's utilities:

from IPython.utils import io
for v in range(10):
    print(v)
    with io.capture_output() as captured:
      installAdjust()

For the future, whenever a magic function doesn't suffice, search for the core properties being accessed and access them yourself.

Answer sourced from: How do you suppress output in IPython Notebook?

Rub · Answer 3 · 2022-04-13T07:51:30.570

Simply append to the command an output redirection:

Redirect output AND errors, add &> /dev/null

!mkdir /content/notexist/blah &> /dev/null

Redirect output, but NOT errors, add > /dev/null

!mkdir /content/notexist/yeaa > /dev/null

In the example below, both commands fail, but we ignore the error from the second.

Specifically for your case, the code would be:

%%capture
def installAdjust():
    !pip install adjustText &> /dev/null

How to suppress output in Google Colaboratory cell which executes a command line script (line starts with `!`) via a function

3 Answers3