Hello Python

Hello My Love Python.
I want to learn Python from long long ago when I am at Japan.
python use indent instead of () and {}, functionalable

python syntax

1. print

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print("hello-world")
print(12 + 13)
print("my first python code")

2. input

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name = input()
print(name)

3. Boolean

basic Boolean

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True
False

Boolean operator

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and/or/not

eg.

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True and False
True or False
not True

4. if else statement

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if age >= 18:
	print("adult")
else:
	print("teenager")

5. None

  • Like java’s null or like scala’s None

6. Variable

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name = "Jack Zhao" #String
true = True #Boolean
one = 1# Int

7. comments

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# one row comment
'''
multi rows comments
'''

8. constant

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age = 18

9. unicode and utf-8

ord(‘A’): Get char ‘A’ unicode code
chr(65): change code to char

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print(ord('A'))
>>>65
print(chr(65))
>>>A

10. str length

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len('ABC')
>>>3
len('12')
>>>2

11. format

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%d Int
%f Float
%s String
%x Hex(16)

12. list and tuple

list: can been changed contents

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name = ['jack', 'joy', 'toy']
name[0]
len(name)
name.append('summer')
name.append(1, 'summer')
name.pop()
name.pop(1)

tuple: can’t been changed
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name = ('jack', 'joy', 'toy')

if you define one Int content, you must use “,”, or will been think as defined a Int instead of a tuple.
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name = (1,)

Night is so long, end my active, go to sleep.