Python Learning Manual, Char 14-15

Char 14 iterators and parsers

Iterative: An object that supports ITER

Iterator: An object returned by ITER that supports next (I)

These functions are automatically called by the Python iteration tool, and we can also manually apply the iteration protocol

Char 15 Documentation

1 writing Python's documentation resources

Python Documentation Resources
Form	Role
# Notes	Documents in the file
Dir function	List of available properties in an object
Document string: __doc__	Documents attached to a file on an object
Pydoc:help function	Interactive Help for objects
pydoc:html Report	Module documentation in the browser
Standard Manual	Official Language and library instructions
Site Resources	Online tutorials, examples, etc.

2 The dir result of any built-in type contains a set of properties that are related to the implementation of the type

3 document String that appears at the beginning of the file and at the start of its functions and classes

classDemo (object):" "Demo Desc" "    defTest (self):" "desc:only Test:return:" "        Print('Test')Print(Demo.)__doc__)Print(Demo (). Test.__doc__)" "Run Result Demo Desc desc:only test:return:" "

4 common pitfalls for writing code

1) Don't forget the colon.

2) Start with the first line

3) Blank lines are important at the interactive mode prompt

4) indent to be consistent

5) do not write C code in Python

6) Use a simple for loop instead of while or range

For is faster than while, because Python handles index operations internally for a simple for loop

7) Be aware of mutable objects in assignment statements

8) do not expect in the distance the function of the Fat object will return the result

Eg:list.sort () returns none, List2 = sorted (lsit)

9) Be sure to use the () Call function

10) Do not use extensions or paths in import and reload

Eg:model name:basecal.py, import basecal [Yes]; Import basecal.py [NO]

　　

Python Learning Manual, Char 14-15