While using cython in ipython notebook, I see the error below. What's wrong?
%load_ext cythonmagic
/usr/local/lib/python2.7/dist-packages/IPython/extensions/cythonmagic.py:21: UserWarning: The Cython magic has been moved to the Cython package
warnings.warn("""The Cython magic has been moved to the Cython package""")
%%cython
def fib(int n):
cdef int a,b,i
for i in range(n):
a,b=a+b,b
return a
ERROR: Cell magic `%%cython` not found.
What the warning is trying to communicate is that the extension defining the %%cython magic has moved to the Cython package, out of the IPython package. So instead of
%load_ext cythonmagic
you should do:
%load_ext Cython
After that, the cython magic should work as expected.
Remember to load the extension in a different cell.
If you load and use the Cython extension in the same cell, you will fall in error:
Using the same cell:
Using a different cell:
Related
I start a new project library with cabal. here is the .cabal file
cabal-version: 2.4
library
exposed-modules: MyLib
build-depends: base ^>=4.14.3.0
, vector
hs-source-dirs: src
default-language: Haskell2010
I then use some Data.Vector functions inside my code. Here is the MyLib source
module MyLib (someFunc) where
import qualified Data.Vector as V
func :: [a] -> V.Vector a
func a = V.fromList a
But Data.Vector module remains underlined in red and this error is shown inside Vcode:
Could not load module ‘Data.Vector’
It is a member of the hidden package ‘vector-0.13.0.0’.
the func function works when in cabal repl
when I try cabal install vector this error appears:
Wrote tarball sdist to
/home/. .. .tar.gz
Resolving dependencies...
cabal: Cannot build the executables in the package vector because it does not
contain any executables. Check the .cabal file for the package and make sure
that it properly declares the components that you expect.
I don't understand what I am doing wrong? I told I understood the workings of cabal: I import a module as a dependency in .cabal, and I should be able to use it? why VSC does tell me he can't find it?
I have used the following scripts in an iPython notebook to enable autoreload.
import autoreload
%autoreload
The import works find but the magic function throws the following error:
ERROR: Line magic function `%autoreload` not found.
Here are the current version settings as per the notebook 'about' section:
Python 2.7.3 (default, Jun 22 2015, 19:33:41)
[GCC 4.6.3]
IPython 4.1.2 -- An enhanced Interactive Python.
Any pointers on what the issue could be would be appreciated.
Thanks
If you are using this in IPython notebook
This command will load autoreload:
%load_ext autoreload
This line will reload pandas (replace pandas with the module name you would like to reload) every time code is run:
%aimport pandas
If you wish to remove pandas from reloading every time you run code then,
this line will stop pandas from reloading:
%aimport -pandas
Include %autoreload at the top the cell for the magic to happen!
autoreload Reference
does anyone know if there is a way to print the compiler (and its version) that is used when I use the Fortran magic and Cython magic in IPython
For example, like the compiler that was used to build Python: platform.python_compiler()
There are probably better ways to do this, but here are two quick ones.
For Cython, the first thing that came to mind was to make a Cython file that passes the Cython compiler and causes an error at the C level.
Here's a simple one.
cdef extern from "nosuchheader.h":
void myfakefunction(int a, double b)
On my computer IPython shows an error from distutils saying that "gcc failed with exit status 1".
I don't currently use the %%fortran magic, but you should be able to see what f2py is doing based on its output.
f2py usually shows which compiler it is using, both when it searches for a compiler, and when it actually calls the Fortran compiler.
To figure that out, I'd recommend compiling some snippet of Fortran code via f2py and looking at the output.
On my windows machine it shows the output as f2py searches for a Fortran compiler, and prints the lines
'Found executable C:\\mingw64\\bin\\gfortran.exe',
'Found executable C:\\mingw64\\bin\\gfortran.exe',
This tells me it is using gfortran.
Further down in the output it also shows the commands used to build the Fortran source code.
The documentation for the fortran magic mentions how to get verbose output.
If you pass the flag -vvv to the fortran magic, it will print the output from f2py.
You could also try looking at the %fortran_config magic mentioned in the documentation.
First of all I'm aware of the question here but I couldn't find a satisfied answer there. I don't want to ignore errors or use comments - I want to have the right settings in eclipse/pydev. My problem is pretty similar to this one.
I'm using Ubuntu 12.04 and installed a virtuenv for python 2.7 in my home directory. After installing several python packages (numpy, scipy, matplotlib, etc.) using pip, I installed eclipse 4.3 with pydev.
If I use the python system interpreter at /usr/bin/python everything works fine (except that I didn't want to use). However, if I try to set up a python interpreter using the virtualenv first I get this warning describe here. After clicking "proceed anyway", it seems to work. So far so good.
However e.g. import numpy as np gives for each np.* call the eclipse/pydev error Undefined variable from import, also the code completion doesn't work properly. It seems to work, e.g. for datetime, but not for numpy, scipy and matplotlib.
Does anybody figured out to configure eclipse correctly?
I already tried to add the numpy path manually to the virtualenv interpreter, but than I get the weird error:
import matplotlib.dates as mpl_dates
File "/home/pydev/myenv-py27/local/lib/python2.7/site-packages/matplotlib/init.py", line 149, in
import sys, os, tempfile
File "/usr/lib/python2.7/tempfile.py", line 34, in
from random import Random as _Random
ImportError: cannot import name Random
I'm trying to write some plugins for the irc bot supybot with eclipse/pydev. Pydev gives me errors about unresolved imports on supybot-modules/packages (e. g. import supybot.utils as utils), but works ok on e. g. "from supybot.commands import *". So I guess I set up dydev correctly, as it finds the wanted modules. The problem must be in pydev/eclipse, as the bot works correct and in eric5 I get also no errors about that.
Removing the interpreter and setting it up didn't help. Any other ideas on how to fix this? System: Arch Linux, Eclipse Juno, PyDev 2.7.1, wanted (and set up) python interpreter is 2.7, supybot is installed in site-packages for Python 2.7.
Edit: Just noticed: PyDev doesn't mark the "from ... import *" as error, but if I use functions imported from there I get an error on that function.
Code sample:
[...]
import supybot.utils as utils
from supybot.commands import *
[...]
wunsch = wrap(wunsch, ['text', 'now'])
[...]
Error on the first line: Unresolved import: utils
Second line gets no error nor warning
Error on 3rd line: Undefined variable: wrap
But 'wrap' is a function declared in supybot.commands
Run import supybot; print supybot.__path__ to get the path to the supybot package. PyDev may be importing the wrong one (for example if you use a folder called supybot in your workspace).