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Python on Linux

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Python

Why Python

• Easy to Learn
• Useful
• Huge Amount of Wheels
  1. Built-in Features
  2. Built-in Libraries
     • devdocs.io
     • (*) IPython + help
  3. 3rd Party Libraries
     • (!) pip3 search
     • Search via Github

IPython

Jupytor Notebook

Built-in Features

Data Type and Conversion

type	description	example
bool	boolean	False
int	integer	117
float	floating point number	1.78
complex	complex number	0.5 + 2.0j
str	string	'abc'
tuple	tuple	(1, 'hmm', 2.0)
list	list	[1, 'hmm', 2.0]
dict	dictionary	{'a': 7.0, 23: True}

Loop: For and While

for i in range(10, 8, -1):
    pass

for el in lst:
    continue

for k, v in dct.items():
    break

while 1:
    pass

Function

def func(foo):
    print('hello world')
    return 'bar'

The Construction of List and Dict

dct = {'x': 'a', 'y': 'b'}
[k + ':' + v for k, v in dct.items()]
{v: k for k, v in dct.items()}

The Missing Else

def print_first_one_larger_than(lst, n):
    for i in lst:
        if i > n:
            print(i)
            break
    else:
        print('None')

print_num_larger_than(range(10), 5)
print_num_larger_than(range(10), 15)

Class

class A:
    b = 3

    def __init__(self, a):
        self.a = a

    def printa(self):
        print(self.a)

    @classmethod
    def printb(cls):
        print(cls.b)

    @staticmethod
    def printc():
        print('c')

Decorator: Functional Programming

def f(x):
    print(x)

def deco(func):
    return lambda x: func(x + 1)

g = deco(f)

@deco
def h(x):
    print(2 * x)

I/O

1. From User: input
2. From Files: open, read, write, close
3. From Internet: urllib, requests

Vim

Why Vim

1. Easy to get
2. Powerful
3. Design It Yourself
4. Lots of Plugins

Learn Vim the Hard Way

1. Learn it once in a while like you didn't.

2. Use it before you master it.

• Modes: i, ESC
  • :w, :q, :q!
• Navigate: hjkl, c-f, c-b
• Undo & Redo: u, c-r
• Cut & Paste: dd, p

3. Know what you don't so you can search for it.

• Navigate like an expert

  • gg, G, 15G
  • H, M, L
  • zz, z-, zEnter
  • Ww, Bb, Ee
  • Ff, Tt
  • ^, $
  • A, I
  • %
  • #, *

• Edit like an expert

  • cdy: change/delete/yank
    • cw, dw, yw
    • dj, 3dd, d15G
  • v, C-v
    • I, $A
  • <<, >> tab & untab

• Reply like an expert

  • ;, .
  • qa, q, @a, 8@a

• Even an expert is afraid of sed

  • :s/x/y/
  • man sed & curl cheat.sh/sed
  • :%s text rpl gc

Vim Challenge

type	description	example
bool	boolean	False
int	integer	117
float	floating point number	1.78
complex	complex number	0.5 + 2.0j
str	string	'abc'
tuple	tuple	(1, 'hmm', 2.0)
list	list	[1, 'hmm', 2.0]
dict	dictionary	{'a': 7.0, 23: True}

Q & A

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