jandyman | 6 Jan 00:05 2016

stupid newbie question

I'm sure this is beyond stupid, but I cannot figure out how to get an ultra
simple command history recall function to work. If I say "%hist -g mystring"
and get a list of commands, I'll see a "column" on the left with appear to
be command numbers. Let's say that I now want to put command 45 on the
prompt line, edit it, and then execute it. I would think I would say
"%recall 45". But this command doesn't seem to do anything. What fundamental
mistake am I making. I have tried this in shells in both IEP and Spyder.

Thanks for any help!

- Andy

View this message in context: http://python.6.x6.nabble.com/stupid-newbie-question-tp5180869.html
Sent from the IPython - User mailing list archive at Nabble.com.
Hughe Chung | 31 Dec 11:27 2015

What would cause empty output cache? And how to fix it?


IPython3 worked fine so I installed jupyter, qtconsole. While I was 
using jupyter, qtconsole back and forth, I noticed qtconsole stopped 
showing [Out ##] prompt. It only showed the output result of input cell.

And IPython 4.0.1 also stopped caching output cells and I couldn't use 
the default variables, _, __, ___, and _[number].

I played with configuration variables that related to caching and 
history for hours in vain. Reinstallation of IPython 4.0.1 fixed it 

 <at> -MinRK

>    python3 -m pip install ipython
I managed to install ipython 4.0.1 after spending hours. I used pip3 
install [module] method.
Darren Govoni | 30 Dec 16:53 2015

FIxed ports for engine/cluster

  I notice every time I run a new cluster it generates the engine json file with all new ports. Problem is this doesn't work real well in a cloud where ports are strictly governed. Is there any way I can assign the set of ports to use?


IPython-User mailing list
IPython-User <at> scipy.org
janpenguin | 24 Dec 12:01 2015

How to upgrade or install Ipython for python 3.x support?


I mostly use ipython as SymPy interface that serves as CAS (Computer 
Algebra System) application in Devuan (Debian without systemd) Linux.

The ipython supports python 2.x I believe.

$ ipython --pylab
Python 2.7.10+ (default, Oct 10 2015, 09:11:24)
Type "copyright", "credits" or "license" for more information.

IPython 2.3.0 -- An enhanced Interactive Python.
?         -> Introduction and overview of IPython's features.
%quickref -> Quick reference.
help      -> Python's own help system.
object?   -> Details about 'object', use 'object??' for extra details.
Using matplotlib backend: TkAgg

I'm planning to replace all previous python codes I've written to Python 
3.x. Is there Ipython version that supports Python 3.x?

Brian Merchant | 10 Dec 18:45 2015

totally replacing bash with IPython on my Linux system

I'd like to replace bash with IPython on my system, so that even files like .profile are in Python rather than shell script.

I have some confusion on the topic, even though asking a few questions on the matter. Here are the questions I have asked previously:

1) How can I replace bash with Python? http://unix.stackexchange.com/questions/176091/how-can-i-replace-bash-with-python

From the answer to that question, I learned how to automatically replace bash with IPython after log in.

2) .profile is written in shell script -- can I get my system to understand that I want it to execute a Python script instead? http://unix.stackexchange.com/questions/248477/profile-is-written-in-shell-script-can-i-instead-make-my-system-understand-th

From the answer to that question, I learned that .profile file is "sourced" rather than "executed" -- that is, the lines in .profile are run one by one, as if one were typing them into the shell.

So, my question now is: how do I get my base system shell to be IPython, so that it can source ".profile" scripts that have IPython magics/Python written inside them? For example, I'd like to write my .profile file using IPython magics/Python.

Kind regards,

IPython-User mailing list
IPython-User <at> scipy.org
Fernando Perez | 19 Nov 22:42 2015

[JOB] Project Jupyter is hiring two postdoctoral fellows <at> UC Berkeley.

Hi all,

We are delighted to announce today that Project Jupyter/IPython has two postdoctoral fellowships open at UC Berkeley, open immediately.  Interested candidates can apply here:


We hope to find candidates who will work on a number of challenging questions over the next few years, as described in our grant proposal here:

Interested candidates should carefully read that proposal before applying to familiarize themselves with the full scope of the questions we intend to tackle.

We'd like to thank the support of the Helmsley Trust, the Gordon and Betty Moore Foundation and the Alfred P. Sloan Foundation.


Brian Granger and Fernando Perez.

Fernando Perez ( <at> fperez_org; http://fperez.org)
fperez.net-at-gmail: mailing lists only (I ignore this when swamped!)
fernando.perez-at-berkeley: contact me here for any direct mail
IPython-User mailing list
IPython-User <at> scipy.org
steffenl | 12 Oct 15:30 2015

Updating a FloatProgress widget within a thread doesn't work anymore in a notebook

I am writing a application that calculates some physical beheaviour based on
user defined models. These calculations have a high workload. Therefore the
user needs some information over the calculation progress. 
It is very difficult to show the progress in a Jupyter notebook. With text
printing the output can not easily get flushed because of the notebooks
output handling. Therefore I used the FloatProgress widget out of the
IPython.html module. I used a threading.Timer to update the widgets value.
This no longer works in the updated ipython version 3.2. 
The widget does not show the actual value. It updates its visual
representation only once after the code in the nodebook cell is already
How is it possible to update the visual representation of the widget during
the computation? The following simplified code can show the problem if it
runs in a notebook cell:

from IPython.html import widgets
from IPython.display import display
import threading

class Counter:
    """Simulates a task with heavy workload.
    The 'value' attribut holds the state of the progress.
    If the value of 'value' reaches the value of the 'max' attribut, 
    the work is done."""

    def __init__(self, max):
        self.max = max
        self.value = 0

    def count(self):
        for i in xrange(self.max + 1):
            for _ in xrange(self.max):
                self.value = i

class ProgressBar(widgets.FloatProgress):  

    def __init__(self, counter):
        super(ProgressBar, self).__init__()        
        self.max = counter.max
        self.counter = counter

    def show_progress(self):
        self._timer = (
                            function=self.show_progress)) # restart timer
        self._timer.daemon = True # kill thread at shut down of main process        
        self.value = self.counter.value # here, the bar should visually
        if self.value >= self.max:
            self.bar_style = 'success'            

c = Counter(10000)
s = ProgressBar(c)

View this message in context: http://python.6.x6.nabble.com/Updating-a-FloatProgress-widget-within-a-thread-doesn-t-work-anymore-in-a-notebook-tp5173902.html
Sent from the IPython - User mailing list archive at Nabble.com.
Omar Andrés Zapata Mesa | 3 Oct 05:47 2015

Running cling kernel

Hi dear ipython developers,
I am trying to run cling kernel but I am getting the next error,

WARNING:root:kernel 82b2aa8f-4df1-47f4-b0cc-fce628f19590 restarted
Traceback (most recent call last):
  File "/usr/lib/python2.7/runpy.py", line 162, in _run_module_as_main
    "__main__", fname, loader, pkg_name)
  File "/usr/lib/python2.7/runpy.py", line 72, in _run_code
    exec code in run_globals
  File "/usr/local/lib/python2.7/dist-packages/clingkernel.py", line 18, in <module>
    from pexpect import replwrap, EOF
ImportError: cannot import name replwrap

I have a fresh install from github repo for ipython and I am using debian sid.

Best regards.
IPython-User mailing list
IPython-User <at> scipy.org
Thomas Robitaille | 29 Sep 15:59 2015

ANN: numtraits v0.2

Hi everyone,

(apologies if you already saw this on the numpy-discussion list. I am
resending it to the scipy-user and ipython-user mailing lists since
these were down last week)

We have released a small experimental package called numtraits that
builds on top of the traitlets package and provides a NumericalTrait
class that can be used to validate properties such as:

* number of dimension (for arrays)
* shape (for arrays)
* domain (e.g. positive, negative, range of values)
* units (with support for astropy.units, pint, and quantities)

The idea is to be able to write a class like:

    class Sphere(HasTraits):

        radius = NumericalTrait(domain='strictly-positive', ndim=0)
        position = NumericalTrait(shape=(3,))

and all the validation will then be done automatically when the user
sets 'radius' or 'position'.

In addition, tuples and lists can get automatically converted to
arrays, and default values can be specified. You can read more about
the package and see examples of it in use here:


and it can be easily installed with

  pip install numtraits

The package supports both Python 3.3+ and Legacy Python (2.7) :)

At this point, we would be very interested in feedback - the package
is still very young and we can still change the API if needed. Please
open issues with suggestions!


Tom and Francesco
Vasco | 25 Sep 09:44 2015

%matplotlib qt hangs notebook

sometimes when I run %matplotlib qt in the ipython notebook (v4), it is 
indicated that the cell is executed and that the kernel is not busy. 
However, the next cell cannot be executed: there appears a *, as should 
be, but there is no output, the * remains, but the kernel does not look 

This mainly happens when I run the second cell, while the %matplotlib qt 
command is not finished yet.

Is this a known problem? How can I diagnose what is going on? I tried to 
start jupyter with --debug flag, but it does not give any errors or 
messages relating the notebook/kernel that is giving problems.

This problem occurs at both a windowsxp machine with the newest python3 
version from anaconda, as on a ubuntu machine, with
* python '3.4.0 (default, Jun 19 2015, 14:20:21) \n[GCC 4.8.2]'
* matplotlib 1.3.1

Both with ipython4 from pypi

Kind regards,
reckoner | 11 Sep 03:58 2015

Re: Connect to remote kernel on AWS using local qtconsole?

For reference, I posted some code and the solution to this problem here: