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How to apply a function to two columns of Pandas dataframe

Suppose I have a df which has columns of 'ID', 'col_1', 'col_2' . And I define a function : 12 Answers ...
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PHP: If internet explorer 6, 7, 8 , or 9

...mp;& $B['v'] <= 8) { // Browsers IE 8 and below } else { // All other browsers } share | improve this answer | follow | ...
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What is the purpose of using -pedantic in GCC/G++ compiler?

... GCC compilers always try to compile your program if this is at all possible. However, in some cases, the C and C++ standards specify that certain extensions are forbidden. Conforming compilers such as gcc or g++ must issue a diagnostic when these extensions are encountered. For example, ...
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What's a good way to extend Error in JavaScript?

...nvironments set the stack property, but fileName and lineNumber are practically useless to be used in inheritance. So, the minimalistic approach is: function MyError(message) { this.name = 'MyError'; this.message = message; this.stack = (new Error()).stack; } MyError.prototype = new Er...
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Always pass weak reference of self into block in ARC?

... be the cause of these blocks retaining self and keeping it from being dealloced ? The question is, should I always use a weak reference of self in a block ? ...
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Can I implement an autonomous `self` member type in C++?

...question, not the answer. In many cases in software development (and especially maintenance) it is helpful to avoid redundancies in the code, so that changing something in one place does not require you to change code in another place. That's the whole point of auto and decltype or in this case of s...
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Fast Linux File Count for a large number of files

...ke a while if there are a lot of them. Also there will be no output until all of the names are read and sorted. Use the ls -f option to turn off sorting. ls -f | wc -l Note that this will also enable -a, so ., .., and other files starting with . will be counted. ...
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What is a NullReferenceException, and how do I fix it?

.... This means you either set it to null, or you never set it to anything at all. Like anything else, null gets passed around. If it is null in method "A", it could be that method "B" passed a null to method "A". null can have different meanings: Object variables which are uninitialized and hence poi...
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Getting a random value from a JavaScript array

... @SapphireSun this is correct. Note the Math.floor(Math.random(...)) call, which rounds down. – ashes999 Jan 19 '14 at 12:43 34 ...
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Delete multiple objects in django

...sing a webpage. There is no category to select from so I can't delete from all of them like that. Do I have to implement my own delete form and process it in django or does django have a way to already do this? As its implemented in the admin interface. ...