somilong的博客

转： http://blog.youkuaiyun.com/jobschen/article/details/49559023mac 已经自带python,自带python版本是2.7.10.sudo easy_install pip … … …此处省略N行… … … Installed /Library/Python/2.7/site-packages/p

$sudo pip install matplotlib --upgrade在安装matplotlib包的时候，遇到如下报错：Installing collected packages: six, python-dateutil, pyparsing, numpy, pytz, backports.functools-lru-cache, cycler, subprocess32, matplot...

如下A'表示矩阵的转置基本公式：Y = A * X --> DY/DX = A'Y = X * A --> DY/DX = AY = A' * X * B --> DY/DX = A * B'Y = A' * X' * B --> DY/DX = B * A'1. 矩阵Y对标量x求导：相当于每个元素求导数后转置一下，注意M×N矩阵求导后变成N×M了Y = [y(ij)] -...

import numpy as np0. 生成等差数列np.arange(0, 10, 1, dtype=int) =  [0 1 2 3 4 5 6 7 8 9]  #大于等于0， 小于10，步长为1的等差数列np.arange(10) = [0 1 2 3 4 5 6 7 8 9]   #默认大于等于0， 小于10，步长为1的等差数列1. 生成多维数组，并批量初始化元素1.1生成2*3初始值为...

官方解释：Return coordinate matrices from coordinate vectors.用向量生成坐标矩阵，参数的个数不限制，如下以两个向量入参为例：如： 向量X,YX=[1 2]Y=[3 4 5]xx, yy = np.meshgrid(X, Y)xx=[[1 2] [1 2] [1 2]]

(首选确保正确安装virtualenv和virtualenvwrapper)1. 创建虚拟目录$mkvirtualenv venv12.  列出已存在的虚拟目录$workonvenv1venv23. 激活venv1$ workon venv1(venv1) machinename:~ username$其中(venv1)表示你已经

$ sudo pip install virtualenvThe directory '/Users/jimmy.wj/Library/Caches/pip/http' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permis

jimmywjdeMacBook-Pro:~ jimmy.wj$ sudo pip install -U scikit-learnThe directory '/Users/jimmy.wj/Library/Caches/pip/http' or its parent directory is not owned by the current user and the cache has be

明明有这个库的代码，但是依然报错找不到module：尝试更新matplotlib库，还真解决了这个问题：$sudo pip install matplotlib --upgrade如果更新的时候遇到uninstall six库报错，那么可以修改命令如下，跳过six的更新，详见另一篇博文http://blog.youkuaiyun.com/somilong/article/details/79399248$su...