1，Jupyter NoteBook 常用魔法命令

1path = %pwd
2path

1%cd ..

1%cd "C:\\shidayunpan\\allCCTVResearch\\PythonFiles\\Python数据分析"

1%ls

1%%writefile helloworld.py
2print('Hello world!')
3print('Hello China!')

1%run helloworld.py

1%load helloworld.py

1# %load helloworld.py
2print('Hello world!')
3print('Hello China!')

1x = 1
2y = [1,2,3,4]
3%whos

1%reset

1%del x

1%%time
2x = [i**2 for i in range(10000)]
3y = [i**2 for i in x]

1import time
2tic = time.time()
3x = [i**2 for i in range(10000)]
4y = [i**2 for i in x]
5toc = time.time()
6print('using time:'+str(toc - tic)+'s')