Dynamic programming is an algorithm strategy to solve the problem that defines a state space. These problems can be decomposed into new child problems, and child problems have their own parameters. To solve them, we have to search this state space and evaluate each step when making a decision. Thanks to the fact that this type of problem has a lot of the same state, this technology will not waste time on solving overlapping child problems.
As we've seen, it can also lead to a lot of use of recu
The code is as follows:
MyVar = 1
Def myfunc ():MyVar + = 1
MyFunc ()
will prompt for error:
Unboundlocalerror:local variable ' myVar ' referenced before assignment
Python proposes the following hypothesis: If you assign a value to a variable anywhere within the body of the function, Python adds the name to the local namespace.
Statement MyVar + = 1 assigns a value to the name MyVar, the MyVar is p
In general, in Python, the access rules for class instance properties are fairly straightforward.
However, there are still some areas that are not very intuitive, especially for C + + and Java programmers.
Here, we need to understand the following areas:
1.Python is a dynamic language, and any entity can dynamically add or remove attributes.2. A class defines a
random number from the specified range, in the collection incremented by the specified cardinality, and the base default value is 1.3.random ()--take the number between [0,1]4.seed ([x])--set seed, avoid pseudo-random, can not set5.shuffle (list)-sorts all elements of a sequence randomly6.uniform (x, y)--randomly generates a number between [X, Y] RangeTrigonometric function
ACOs (x)
Returns the inverse cosine radian value of x. The parameter x is the cosine value must be betw
Copy Code code as follows:
MyVar = 1
Def myfunc ():MyVar + 1
MyFunc ()
An error is prompted:
Unboundlocalerror:local variable ' myVar ' referenced before assignment
Python assumes that if you assign a value to a variable anywhere in the body of the function, Python adds the name to the local namespace.
Statement MyVar + = 1 assigns a value to the name MyVar, the MyVar is part of the local
Reprinted from: https://www.cnblogs.com/taurusfy/p/7605787.html***************************************************************************************************The following is the text:A Python project in which one file needs to refer to a class in another file, several problems encountered, summarized as follows:
Situation one: Under the same directory
Directory structure: |--a.py |--b.py |--main.py In main.py, you need to ref
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