Programming Fundamentals Summary 000
1, computer architecture
2, the programming language classification
3, the origin of the character encoding
Computer Architecture
Computer Organization five components: a controller, the arithmetic unit, memory, input, output
The controller (Controler): control information interpreted predetermined program controlled according to its request, scheduler, data, addresses, each part of the work coordinating computer peripherals and memory access and so on.
Operator (Datapath): the data arithmetic and logic operations, data processing;
Memory: store programs, data and all kinds of signals, commands, and other information, and provide this information when needed.
Enter: the program, the raw data, text, characters, control commands cargo data collected in the field and other information into the computer. For example: keyboard mouse camera like a microphone
Output: output the result out information in the intermediate or final results of the computer, the various data symbols and text in the machine or various control signals. For example: a printer, a display, a speaker, a plotter.
Computer software category:
System software, application software
System software: operating system Linux Windows MAC
Applications: various APP, micro-channel, QQ, deft like.
Programming languages Category:
Compiled languages: C .NET language such as C ++ language
Interpreted languages: Java, Python
Compiled language: Source ------- ---- compiled "intermediate files (.o, and .obj) --------- --------- connection and assembler - "machine code (binary) ---" exe executable file
Compiled language must be compiled in the execution.
An interpreted language: Source --- compiling - "bytecode interpreter --- -----" executable machine code corresponding platform
Python basis
Direct assignment:
a = 1
b = 2
c = 3
Do not declare the type of view variable type print ( "type (a)")
Variable naming rules: 1, can not start with a number;
2, do not use the keyword variable;
3, constitute the variable name: alphanumeric characters and underscores
4, variable names do see the name to know as much as possible Italian
Notes Python way:
1, single-line comments to "#" start
2, three multi-line comment with the three single or double quotes
a = 1 # variable assignment
b = 2 ''' asdfsdafasdfasfasfass
asdfasfasdfasf
'''
c = 3 """ asdfadsfasdfasfas
"""
String manipulation:
Stitching: +
copy:*
Takes a string of characters: []
Slicing all characters starting at start before taken to end: [step start:: end ]
• [:] extracted from the beginning to the end of the entire string
• [start:] extracted from the start to the end
• [: end] extract from beginning to End - 1
• [start: End] extracted from start to End - 1
• [ start: end: step] extracted from the start to the end - 1, each step extracting a character
Use len () obtained length
>>> len(letters)
26
>>> empty = ""
>>> len(empty)
0
Use split () split
>>> todos = 'When HHH , apple banana orange, water milk juice'
>>> todos.split(',')
['When HHH ', ' apple banana orange', ' water milk juice']
Use join () merge
>>> Lista = ['one','two','three','four']
>>> ListaString = ','.join(Lista)
>>> ListaString
'one,two,three,four'
>>>
Capitalization and alignment
The ending of the string are deleted out:
>>> Setup .strip ( '.')
'A Duck goes INTO A bar'
Let string first letter capitalized :
>>> Setup .capitalize ()
'A Duck goes INTO A bar ...'
all words beginning with the letter capitalized :
>>> Setup .title ()
'A Duck Goes into A Bar ... '
so that all the letters are capitalized :
>>> Setup .upper ()
' A DUCK GOES iNTO A BAR ... '
will convert all letters to lowercase :
>>> Setup .lower ()
' a duck goes into a bar ... '
to all the letters case conversion :
>>> Setup .swapcase ()
' the INTO a a DUCK the bAR ... the gOES '
Use replace () Replace
The last parameter is omitted if only the first alternative default
Python basic elements: a position number, the first occurrence of the string and the variables:
>>> Setup .replace ( 'Duck', 'marmoset')
'A marmoset goes INTO A bar .. '
modify 100 up :
>>> Setup .replace (' A ',' A Famous', 100 )
'A Famous Duck goes Famous INTO A bar ...'