Best general purpose – Especially short arrays (1000 items or less) and coders that are unsure of what optimizations best suit their needs. # $value can be any regex. be safe if ( grep( /^$value$/, @array ) ) { print “found it”; } It has been mentioned that grep passes through all values even if … Read more
Summary: Use is when you want to check against an object’s identity (e.g. checking to see if var is None). Use == when you want to check equality (e.g. Is var equal to 3?). Explanation: You can have custom classes where my_var == None will return True e.g: class Negator(object): def __eq__(self,other): return not other … Read more
Here are the rules for how these functions work: stringValue.CompareTo(otherStringValue) null comes before a string it uses CultureInfo.CurrentCulture.CompareInfo.Compare, which means it will use a culture-dependent comparison. This might mean that ß will compare equal to SS in Germany, or similar stringValue.Equals(otherStringValue) null is not considered equal to anything unless you specify a StringComparison option, it … Read more
By default, the datetime object is naive in Python, so you need to make both of them either naive or aware datetime objects. This can be done using: import datetime import pytz utc=pytz.UTC challenge.datetime_start = utc.localize(challenge.datetime_start) challenge.datetime_end = utc.localize(challenge.datetime_end) # now both the datetime objects are aware, and you can compare them Note: This would … Read more
If you want them to be really equal (i.e. the same items and the same number of each item), I think that the simplest solution is to sort before comparing: Enumerable.SequenceEqual(list1.OrderBy(t => t), list2.OrderBy(t => t)) Edit: Here is a solution that performs a bit better (about ten times faster), and only requires IEquatable, not … Read more
When I looked at the solutions in the other answers I saw some things that I know are bad for performance. I was going to put them in a comment but I thought it was better to benchmark it and share the results. You can test it yourself. Below are my results (ymmv) normalized after … Read more
If you want to know how many values match in both the dictionaries, you should have said that 🙂 Maybe something like this: shared_items = {k: x[k] for k in x if k in y and x[k] == y[k]} print(len(shared_items))
Python has a built-in datatype for an unordered collection of (hashable) things, called a set. If you convert both lists to sets, the comparison will be unordered. set(x) == set(y) Documentation on set EDIT: @mdwhatcott points out that you want to check for duplicates. set ignores these, so you need a similar data structure that … Read more
I was a member of the IEEE-754 committee, I’ll try to help clarify things a bit. First off, floating-point numbers are not real numbers, and floating-point arithmetic does not satisfy the axioms of real arithmetic. Trichotomy is not the only property of real arithmetic that does not hold for floats, nor even the most important. … Read more
What does it mean for the ranges to overlap? It means there exists some number C which is in both ranges, i.e. x1 <= C <= x2 and y1 <= C <= y2 To avoid confusion, considering the ranges are: [x1:x2] and [y1:y2] Now, if we are allowed to assume that the ranges are well-formed … Read more