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Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...a,2) by compiling it into a*a , but the call pow(a,6) is not optimized and will actually call the library function pow , which greatly slows down the performance. (In contrast, Intel C++ Compiler , executable icc , will eliminate the library call for pow(a,6) .)
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What is causing this ActiveRecord::ReadOnlyRecord error?
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Rails 2.3.3 and lower
From the ActiveRecord CHANGELOG(v1.12.0, October 16th, 2005):
Introduce read-only records. If you call object.readonly! then it will
mark the object as read-only and raise
ReadOnlyRecord if you call
obje...
Ternary Operators in JavaScript Without an “Else”
...ested expressions if that is fitting)
each part of the expression (after ? and after : ) should return a value without side effects (the expression x = true returns true as all expressions return the last value, but also changes x without x having any effect on the returned value)
In short - the '...
When monkey patching an instance method, can you call the overridden method from the new implementat
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EDIT: It has been 9 years since I originally wrote this answer, and it deserves some cosmetic surgery to keep it current.
You can see the last version before the edit here.
You can’t call the overwritten method by name or keyword. That’s one of the many reasons why monkey patching...
Label encoding across multiple columns in scikit-learn
I'm trying to use scikit-learn's LabelEncoder to encode a pandas DataFrame of string labels. As the dataframe has many (50+) columns, I want to avoid creating a LabelEncoder object for each column; I'd rather just have one big LabelEncoder objects that works across all my columns of data. ...
How do I add 24 hours to a unix timestamp in php?
... Mar 25 '10 at 11:41
Álvaro GonzálezÁlvaro González
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CROSS JOIN vs INNER JOIN in SQL
What is the difference between CROSS JOIN and INNER JOIN ?
12 Answers
12
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Youtube iframe wmode issue
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Differences between opaque and transparent. opaque is supposed to be more performant.
– donut
Sep 14 '11 at 17:36
3
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Create code first, many to many, with additional fields in association table
...table. In a many-to-many relationship EF manages the join table internally and hidden. It's a table without an Entity class in your model. To work with such a join table with additional properties you will have to create actually two one-to-many relationships. It could look like this:
public class ...
How to check a not-defined variable in JavaScript
...nly be done with try/catch, since typeof will treat an undeclared variable and a variable declared with the value of undefined as equivalent.
But, to check if a variable is declared and is not undefined:
if (yourvar !== undefined) // Any scope
Previously, it was necessary to use the typeof opera...