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Difference between numpy.array shape (R, 1) and (R,)

... 1. The meaning of shapes in NumPy You write, "I know literally it's list of numbers and list of lists where all list contains only a number" but that's a bit of an unhelpful way to think about it. The best way to think about NumPy arrays is that they consist of two parts, a data bu...
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What is the difference between varchar and varchar2 in Oracle?

...t rationale before, that's useful. Thanks. For the record, it is still totally ridiculous that the main character type in Oracle is "varchar2". Doesn't that strike anybody else as a terrible kludge? Seems like how I would have solved some problem in my first week of learning to program. ...
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How to create a trie in Python

... Unwind is essentially correct that there are many different ways to implement a trie; and for a large, scalable trie, nested dictionaries might become cumbersome -- or at least space inefficient. But since you're just getting started, I think...
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Divide a number by 3 without using *, /, +, -, % operators

...n which performs the desired operation. But it requires the + operator, so all you have left to do is to add the values with bit-operators: // replaces the + operator int add(int x, int y) { while (x) { int t = (x & y) << 1; y ^= x; x = t; } return y; }...
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What is the difference between char, nchar, varchar, and nvarchar in SQL Server?

...torage space for number of characters you specify even if you don't use up all that space. varchar and nvarchar are variable-length which will only use up spaces for the characters you store. It will not reserve storage like char or nchar. nchar and nvarchar will take up twice as much storage spac...
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What is the difference between linear regression and logistic regression?

...e, and greater than 1 whereas probability can not. As regression might actually produce probabilities that could be less than 0, or even bigger than 1, logistic regression was introduced. Source: http://gerardnico.com/wiki/data_mining/simple_logistic_regression Outcome In linear regression, the...
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How to add a 'or' condition in #ifdef

...ned. If you want it to happen if neither of them are defined, you'd use an AND: #if !defined(CONDITION1) && !defined(CONDITION2). – cp.engr Feb 20 '17 at 18:26 ...
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JavaScript curry: what are the practical applications?

...self—is useful in JavaScript; it is a technique for converting function calls with multiple arguments into chains of function calls with a single argument for each call, but JavaScript supports multiple arguments in a single function call. In JavaScript—and I assume most other actual languages...
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What do the &,

Up until now I have only used database.yml with each parameter called out explicitly, in the file below it uses some characters I do not understand. What does each line and symbol(&,*, ...
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WebService Client Generation Error with JDK8

.../jre/lib and then write this line in it: javax.xml.accessExternalSchema = all That's all. Enjoy JDK 8. share | improve this answer | follow | ...