I got this strange error when installing igraph:
plfit/gss.c: In function ‘gss’:
plfit/gss.c:92: error: ‘NAN’ undeclared (first use in this function)
plfit/gss.c:92: error: (Each undeclared identifier is reported only once
plfit/gss.c:92: error: for each function it appears in.)
plfit/gss.c:93: error: ‘INFINITY’ undeclared (first use in this function)
It turns out to be a compiler standard problem. Adding the flag CFLAGS=’-std=gnu99′ to make solves the problem
Update: Now I would recommend just anaconda python
To be cool in a coffee shop I bought a mac and then I become dumb at work.
Gladly I find these tips on setting up a mac for python
http://hackercodex.com/guide/mac-osx-mavericks-10.9-configuration/
http://hackercodex.com/guide/python-development-environment-on-mac-osx/
I tried to upgrade matplotlib which asked me to upgrade distribute. I upgraded distribute and then easy_install does not work…… It is solved by the following
1. Check your /usr/bin and /usr/local/bin for easy_install installations and remove any old script:
sudo rm /usr/bin/easy_install*
sudo rm /usr/local/bin/easy_install*
2. Download and run distribute:
curl -O http://python-distribute.org/distribute_setup.py
sudo python distribute_setup.py
sudo rm distribute_setup.py
use the subprocess module. os.system is outdated.
import subprocess output=subprocess.check_output(['wc',filename])
\usepackage{amsmath}
Then use the \substack command.
\lim_{\substack{x\rightarrow 0\\y\rightarrow 0}} f(x,y)
copied from http://blog.32leaves.net/?p=262
from scipy import sparse
from multiprocessing import Pool
import multiprocessing
import functools
def myfunc(x,ns):
A=ns.A
return A[x,:]*A*A[:,x]
manager = multiprocessing.Manager()
Global = manager.Namespace()
pool=Pool()
Global.A=sparse.rand(10000,10000,0.5,'csr')
myfunc2=functools.partial(myfunc,ns=Global)
r=pool.map(myfunc2, range(100))
random.sample() samples without replacement. I find this piece of code by Sean Ross which samples with replacement.
# credit author(s) of random.py
import random
import itertools
def sample_wr(population, k):
"Chooses k random elements (with replacement) from a population"
n = len(population)
_random, _int = random.random, int # speed hack
return [population[_int(_random() * n)] for i in itertools.repeat(None, k)]
