## Reduced density matrix and partial trace

The reduced matrix is defined as the partial trace of the density matrix. In linear algebra and functional analysis, the partial trace is a generalization of the trace. Whereas the trace is a scalar valued function on operators, the partial trace is an operator-valued function. The partial trace has applications in quantum information and decoherence which is relevant for quantum measurement and thereby to the decoherent approaches to interpretations of quantum mechanics, including consistent histories and the relative state interpretation.

## ipynb2pelican Plugin released!

Yet another Pelican Plugin for blogging with Jupyter Notebooks using MetaCell to store metadata.

Thanks to super cow power of python, we can finally publish ipynb easily! Below is the …

## 24 Game Solver

24 game is an arithmetic game with a simple rule: Given 4 numbers and use + - * / to get 24.

• A simple example is 1, 2, 3, 4, and you find 1 …

## 默认目录¶

jupyter notebook --generate-config
vim /home/zpj/.jupyter/jupyter_notebook_config.py#查找dir设定notebook根目录

## 配置pylab, matplotlib默认载入¶

%pylab
%matplotlib inline
%config …

## Python plotting with infinite incontinuous point

In [2]:
def tannan(x, bound=6):
t=tan(x)
if abs(t)>bound:
return nan
else:
return t
tann=vectorize(tannan)
x …