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What is an undefined reference/unresolved external symbol error and how do I fix it?
					What are undefined reference/unresolved external symbol errors? What are common causes and how to fix/prevent them?
                    
                    
                        
                            
                                
                                        34 Answ...				
				
				
							A Regex that will never be matched by anything
					...atch a character a after the end of the string. Good luck.
WARNING:
This expression is expensive -- it will scan the entire line, find the end-of-line anchor, and only then not find the a and return a negative match. (See comment below for more detail.)
* Originally I did not give much thought o...				
				
				
							Does Python have a ternary conditional operator?
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Yes, it was added in version 2.5. The expression syntax is:
a if condition else b
First condition is evaluated, then exactly one of either a or b is evaluated and returned based on the Boolean value of condition. If condition evaluates to True, then a is evaluate...				
				
				
							Passing functions with arguments to another function in Python?
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                I find that the limited syntax is nearly opaque; they're hard to explain to n00bz.  Yes, they do work here, and the confusing features of the syntax are absent.  This is -- perhaps -- the only example I've seen of a lambda that's not obscure.
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							Where do I find old versions of Android NDK? [closed]
					...he link to the NDK that you want and download it from dl.google.com: 
Linux example:
http://dl.google.com/android/ndk/android-ndk-r9b-linux-x86.tar.bz2
http://dl.google.com/android/ndk/android-ndk-r9b-linux-x86_64.tar.bz2
OS X example:
http://dl.google.com/android/ndk/android-ndk-r9b-darwin-x86.ta...				
				
				
							How to validate an email address in PHP
					...emailaddress
}
Additionally you can check whether the domain defines an MX record:
if (!checkdnsrr($domain, 'MX')) {
    // domain is not valid
}
But this still doesn't guarantee that the mail exists. The only way to find that out is by sending a confirmation mail.
Now that you have your eas...				
				
				
							Python: Find in list
					... the elements inside myList. Maybe you try to find a string that does not exactly match one of the items or maybe you are using a float value which suffers from inaccuracy.
As for your second question: There's actually several possible ways if "finding" things in lists.
Checking if something is in...				
				
				
							Can't get rid of header X-Powered-By:Express
					I am running a server on nodejs with express. I can't seem to get rid of the header:
                    
                    
                        
                            
                                
                                        13 Answers
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							Determine if two rectangles overlap each other?
					...ts from the user to construct rectangles (between 2 and 5): height, width, x-pos, y-pos. All of these rectangles will exist parallel to the x and the y axis, that is all of their edges will have slopes of 0 or infinity.
                    
                    
                        
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							Principal component analysis in Python
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I have not had the chance to test it myself, but I've bookmarked it exactly for the PCA functionality.
    
    
        
            
            
                
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