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how does multiplication differ for NumPy Matrix vs Array classes?
The numpy docs recommend using array instead of matrix for working with matrices. However, unlike octave (which I was using till recently), * doesn't perform matrix multiplication, you need to use the function matrixmultipy(). I feel this makes the code very unreadable.
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Calculate the execution time of a method
I have an I/O time-taking method which copies data from a location to another. What's the best and most real way of calculating the execution time? Thread ? Timer ? Stopwatch ? Any other solution? I want the most exact one, and briefest as much as possible.
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Why is inserting in the middle of a linked list O(1)?
According to the Wikipedia article on linked lists , inserting in the middle of a linked list is considered O(1). I would think it would be O(n). Wouldn't you need to locate the node which could be near the end of the list?
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MongoDB/NoSQL: Keeping Document Change History
A fairly common requirement in database applications is to track changes to one or more specific entities in a database. I've heard this called row versioning, a log table or a history table (I'm sure there are other names for it). There are a number of ways to approach it in an RDBMS--you can wri...
Is there a “null coalescing” operator in JavaScript?
Is there a null coalescing operator in Javascript?
13 Answers
13
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How do I assert an Iterable contains elements with a certain property?
Assume I want to unit test a method with this signature:
7 Answers
7
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Why would one use nested classes in C++?
Can someone please point me towards some nice resources for understanding and using nested classes? I have some material like Programming Principles and things like this IBM Knowledge Center - Nested Classes
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Oracle “Partition By” Keyword
Can someone please explain what the partition by keyword does and give a simple example of it in action, as well as why one would want to use it? I have a SQL query written by someone else and I'm trying to figure out what it does.
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Is there an auto increment in sqlite?
I am trying to create a table with an auto-incrementing primary key in Sqlite3 . I am not sure if this is really possible, but I am hoping to only have to designate the other fields.
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What would cause an algorithm to have O(log n) complexity?
My knowledge of big-O is limited, and when log terms show up in the equation it throws me off even more.
6 Answers
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