0基础入门学习Python（第1-2章）

第一章：就这么愉快的开始吧

1.1获取Python

Python3.7

1.2从idle启动

Python 3.7.3 (default, Mar 27 2019, 09:23:39)
[Clang 10.0.0 (clang-1000.11.45.5)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> print("I Love China")
I Love China
>>>

1.3失败的尝试

Python2

Python 2.7.16 (default, Mar 4 2019, 09:02:22)
[GCC 4.2.1 Compatible Apple LLVM 10.0.0 (clang-1000.11.45.5)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> print "I Love China"
I Love China
>>>

Python 3.7.3 (default, Mar 27 2019, 09:23:39)
[Clang 10.0.0 (clang-1000.11.45.5)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> print("I Love China")
I Love China
>>> print "I Love China"
File "<stdin>", line 1
print "I Love China"
^
SyntaxError: Missing parentheses in call to 'print'. Did you mean print("I Love China")?
>>>

1.4尝试点新的东西

>>> print(5+3)
8
>>> 5+3
8
>>> 1234567890987654321 * 9876543210123456789
12193263121170553265523548251112635269
>>> print("Well water " + "River")
Well water River
>>>

1.5  为什么会这样

>>> print("I Love China\n" * 3)
I Love China
I Love China
I Love China

>>> print("I Love China\n" + 3)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: can only concatenate str (not "int") to str
>>>

第二章：用Python设计第一个游戏

猜数字游戏

# date: 2019/8/13
'''----第一个小游戏---'''

temp = input("不妨猜一下小甲鱼现在心里想的是哪个数字：")
guess = int(temp)

if guess == 8:
    print("你是小甲鱼心里的蛔虫吗？")
    print("哼，猜中了也没有奖！")
else:
    print("猜错了，小甲鱼现在心里想的是8！")
print("游戏结束，不玩啦！^_^")

游戏运行下：

BIF 概念

BIF 就是built-in function 内置函数的意思。为了方便程序员快速的编写脚本，Python提供了非常丰富的内置函数，只需要直接引用即可。

print() 就是一个内置函数，他的功能就是，打印到屏幕。

查看Python内置的函数。

>>> dir(__builtins__)
['ArithmeticError', 'AssertionError', 'AttributeError', 'BaseException', 'BlockingIOError', 'BrokenPipeError', 'BufferError', 'BytesWarning', 'ChildProcessError', 'ConnectionAbortedError', 'ConnectionError', 'ConnectionRefusedError', 'ConnectionResetError', 'DeprecationWarning', 'EOFError', 'Ellipsis', 'EnvironmentError', 'Exception', 'False', 'FileExistsError', 'FileNotFoundError', 'FloatingPointError', 'FutureWarning', 'GeneratorExit', 'IOError', 'ImportError', 'ImportWarning', 'IndentationError', 'IndexError', 'InterruptedError', 'IsADirectoryError', 'KeyError', 'KeyboardInterrupt', 'LookupError', 'MemoryError', 'ModuleNotFoundError', 'NameError', 'None', 'NotADirectoryError', 'NotImplemented', 'NotImplementedError', 'OSError', 'OverflowError', 'PendingDeprecationWarning', 'PermissionError', 'ProcessLookupError', 'RecursionError', 'ReferenceError', 'ResourceWarning', 'RuntimeError', 'RuntimeWarning', 'StopAsyncIteration', 'StopIteration', 'SyntaxError', 'SyntaxWarning', 'SystemError', 'SystemExit', 'TabError', 'TimeoutError', 'True', 'TypeError', 'UnboundLocalError', 'UnicodeDecodeError', 'UnicodeEncodeError', 'UnicodeError', 'UnicodeTranslateError', 'UnicodeWarning', 'UserWarning', 'ValueError', 'Warning', 'ZeroDivisionError', '_', '__build_class__', '__debug__', '__doc__', '__import__', '__loader__', '__name__', '__package__', '__spec__', 'abs', 'all', 'any', 'ascii', 'bin', 'bool', 'breakpoint', 'bytearray', 'bytes', 'callable', 'chr', 'classmethod', 'compile', 'complex', 'copyright', 'credits', 'delattr', 'dict', 'dir', 'divmod', 'enumerate', 'eval', 'exec', 'exit', 'filter', 'float', 'format', 'frozenset', 'getattr', 'globals', 'hasattr', 'hash', 'help', 'hex', 'id', 'input', 'int', 'isinstance', 'issubclass', 'iter', 'len', 'license', 'list', 'locals', 'map', 'max', 'memoryview', 'min', 'next', 'object', 'oct', 'open', 'ord', 'pow', 'print', 'property', 'quit', 'range', 'repr', 'reversed', 'round', 'set', 'setattr', 'slice', 'sorted', 'staticmethod', 'str', 'sum', 'super', 'tuple', 'type', 'vars', 'zip']
>>>

help() 用于显示BIF的功能描述

>>> help(print)

Help on built-in function print in module builtins:

print(...)
print(value, ..., sep=' ', end='\n', file=sys.stdout, flush=False)

Prints the values to a stream, or to sys.stdout by default.
Optional keyword arguments:
file: a file-like object (stream); defaults to the current sys.stdout.
sep: string inserted between values, default a space.
end: string appended after the last value, default a newline.
flush: whether to forcibly flush the stream.

完！