comparison - w3toppers.com

How does a Python set([]) check if two objects are equal? What methods does an object need to define to customise this?

Yes, you need a __hash__()-method AND the comparing-operator which you already provided. class Item(object): def __init__(self, foo, bar): self.foo = foo self.bar = bar def __repr__(self): return “Item(%s, %s)” % (self.foo, self.bar) def __eq__(self, other): if isinstance(other, Item): return ((self.foo == other.foo) and (self.bar == other.bar)) else: return False def __ne__(self, other): return (not self.__eq__(other)) … Read more

How to compare two time stamp in format “Month Date hh:mm:ss” to check +ve or -ve value

FIRST- use difftime to compare: you can simply use difftime() function to compare time and return 1 or -1 as follows: int comparetime(time_t time1,time_t time2){ return difftime(time1,time2) > 0.0 ? 1 : -1; } SECOND- Convert string into time: If you have difficulty to convert string into time_t struct, you can use two functions in … Read more

Why do integers in PowerShell compare by digits?

This is because you’re comparing a string to an integer. The order matters. “56” -lt 7 Is actually the same as: “56” -lt “7” Alternatively: 56 -lt “7” would give you the correct result. PowerShell tries to coerce the right side argument to the type of the left side. You might try an explicit cast: … Read more

Javascript – deepEqual Comparison

As you suspect, you’re returning the match of the first property seen. You should return false if that property doesn’t match, but keep looking otherwise. Also, return false if there’s no prop property found on y (that is, the counts match, but not the actual properties). If all properties have matched, return true: var deepEqual … Read more

What are the most important functional differences between C# and VB.NET?

The linked comparisons are very thorough, but as far as the main differences I would note the following: C# has anonymous methodsVB has these now, too C# has the yield keyword (iterator blocks)VB11 added this VB supports implicit late binding (C# has explicit late binding now via the dynamic keyword) VB supports XML literals VB … Read more

How do I deal with “signed/unsigned mismatch” warnings (C4018)?

It’s all in your things.size() type. It isn’t int, but size_t (it exists in C++, not in C) which equals to some “usual” unsigned type, i.e. unsigned int for x86_32. Operator “less” (<) cannot be applied to two operands of different sign. There’s just no such opcodes, and standard doesn’t specify, whether compiler can make … Read more

What is the difference between ImageMagick and GraphicsMagick?

As with many things in life, different people have different ideas about what is best. If you ask a landscape photographer who wanders around in the rain in Scotland’s mountains which is the best camera in the world, he’s going to tell you a light-weight, weather-sealed camera. Ask a studio photographer, and he’ll tell you … Read more

java.lang.IllegalArgumentException: Comparison method violates its general contract [duplicate]

Your compare() method is not transitive. If A == B and B == C, then A must be equal to C. Now consider this case: For A, B, and C, suppose the containsKey() method return these results: childMap.containsKey(A.getID()) returns true childMap.containsKey(B.getID()) returns false childMap.containsKey(C.getID()) returns true Also, consider orders for A.getId() != B.getId(). So, A … Read more

comparison between string literal

char arrays or char pointers aren’t really the same thing as string class objects in C++, so this if (option == “foo”) Doesn’t compare the string option to the string literal “foo” it compares the address of option with the address of the string literal “foo”. You need to use one of the many string … Read more

Why Java does not see that Integers are equal?

Check out this article: Boxed values and equality When comparing wrapper types such as Integers, Longs or Booleans using == or !=, you’re comparing them as references, not as values. If two variables point at different objects, they will not == each other, even if the objects represent the same value. Example: Comparing different Integer … Read more