Make ipython notebook print in real time

This is merely one of the answers to the question suggested by Carsten incorporating the __getattr__ delegation suggested by diedthreetimes in a comment:

import sysoldsysstdout = sys.stdoutclass flushfile():    def __init__(self, f):        self.f = f    def __getattr__(self,name):         return object.__getattribute__(self.f, name)    def write(self, x):        self.f.write(x)        self.f.flush()    def flush(self):        self.f.flush()sys.stdout = flushfile(sys.stdout)

In the original answer, the __getattr__ method is not implemented. Without that, it fails. Other variants in answers to that question also fail in a notebook.

In a notebook, sys.stdout is an instance of IPython.kernel.zmq.iostream.OutStream and has a number of methods and attributes not present in the usual sys.stdout. Delegating __getattr__ allows a flushfile to masquerade as a ...zmq.iostream.OutStream duck.

This works in a python 2.7 notebook run with ipython 3.1.0

Since Python 3.3, print() has an additional flush argument that can be used to force flushing:

for i in range(10):    print(i, flush=True)    time.sleep(1)  

Try this:

from IPython.display import display, clear_outputdisplay("Hello World") # print stringdisplay(df) # print object such as dataframeclear_output(wait=True) # use this if need to clear the output before display, good for dynamic updates