~1 min read

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  1. clear all the variables in Sypder
    import sys
    sys.modules[__name__].__dict__.clear()
    
  2. Some tips (python notebook)
                   #shift + enter to run lines
                   #triple quotes for multi-line string
                   #underscore denotes result from last operation
    !ls               #see what's in dir
    range?            #check info about "range"
    something.        #press Tab to see options
    x,y = y,x         #easy swap, multipal assign
    bool(-1)          #see Boolean data type
    str(13)           #Matlab num2str(13) equivalent
    print(type(True)) #see the data type, will return bool
    x=range(4)        #return [0,1,2,3]
    
  3. Keep in mind that in Python2: 5/2=2; 5/2.0=2.5; Python3: 5/2=2.5;
  4. Getting input from user
    faren = float(input("enter a temperature (in F): "))
    print "Temperature in C is " + str((faren - 32) / 1.8)faren = float(input("enter a temperature (in F): "))
    print "Temperature in C is " + str((faren - 32) / 1.8)
    
  5. The indexing

Screen Shot 2014-09-22 at 4.49.13 PM

http://nbviewer.ipython.org/gist/anonymous/96fa78e3280c5ada1269

  1. The data structures

http://nbviewer.ipython.org/gist/hydro-tian/70491b27495b90c4aa48

  1. Magic line
    %timeit        #timing one line
    %%timeit       #timing the whole cell
    %%bash         #turn whole cell to bash, same as ruby,html,etc.
    %%file text.py #put in the 1st line, will save and overwrite the content in the cell to this file
    %debug         #debug mode
    %matplotlib inline # put plots in the cell
    %lsmagic       #list other available magic lines
    
  2. Matplotlib 101

http://nbviewer.ipython.org/gist/hydro-tian/7df6738e7afa778ad5e6