Defines a generalized comparison method that a value type or class implements to create a type-specific comparison method for ordering instances.
Questions tagged [icomparable]
264 questions
5
votes
3 answers
CompareTo behaviour for double.NaN and double.NegativeInfinity
I was doing some statistical operations in C# (.Net 4) with double[] then i found some strange behavior with CompareTo method and double.NaN. when I try this code:
double.NaN.CompareTo(double.NegativeInfinity) //returns -1
It means double.NaN is…
Hossein Narimani Rad
- 31,361
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5
votes
3 answers
how to handle double.NaN for Generic method accepting IComparable in C#
I have a generic GetMinimum method. It accepts array of IComparable type (so it may be string[] or double[]). in the case of double[] how can I implement this method to ignore the double.NaN values? (I'm looking for good practices)
when I pass this…
Hossein Narimani Rad
- 31,361
- 18
- 86
- 116
5
votes
3 answers
C# generic class and EqualityComparer
Could anyone explain me what's wrong in the following class declaration:
private class PriorityQueueEntry :
IComparer>
where…
Heisenbug
- 38,762
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- 190
4
votes
2 answers
How to Naturally Sort a DataView with something like IComparable
My DataView is acting funny and it is sorting things alphabetically and I need it to sort things numerically. I have looked all across the web for this one and found many ideas on how to sort it with ICompare, but nothing really solid.
So my…
SpoiledTechie.com
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4
votes
3 answers
F# Set using custom class
I'm trying to use Set operations with a class that I have. Every instance of this class has a unique ID. Do I need to implement the System.IComparable interface and if so how would I?
type SomeClass(id : int) =
member this.ID = id
let someSet…
bhd739ge
- 43
- 3
4
votes
3 answers
Why Can I Cast an Int to IComparable?
I had a question on a quiz that asked "What is the following doing?":
// Value is an int
IComparable thing = (IComparable)value;
Apparently the answer is boxing, but I don't know why. Why is this considered boxing and what is it doing? I was under…
user11910061
4
votes
2 answers
Generic List and IComparable Sorting Error: Can not convert lambda expression
I have implemented my own GenericList and Task classes such as:
public GenericList where T: Task
{
public List list = new List();
....
public void Sort()
{
list = list.Sort((a,b) => b.Id.CompareTo(a.Id) > 0);
//here I am…
user8738888
4
votes
5 answers
Where is my IComparable Implementation going wrong?
namespace SortableLists
{
using System;
using System.Collections.Generic;
public class Program
{
private static void Main() {
var list = new List
{
…
Perpetualcoder
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4
votes
4 answers
Sorting list of interface reference objects inherting ICompareable
I was having trouble with list.Sort() for a list of interface references that point to different types however the question Sort a list of interface objects provided the following solution solution
interface IFoo : IComparable
{
int…
Jack Blackmore
- 117
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4
votes
2 answers
Is IComparable the best way to use to enforce unique keys in Dictionary?
I have a class MyClass, and I want to put it as the key to a Dictionary like so:
Dictionary dict = new Dictionary();
I want to ensure that MyClass is a unique key, and uniqueness is specified by looking at…
user3685285
- 6,066
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4
votes
4 answers
Difference between IComparable and IComparable in this search method
I know that there is a big difference between IComparable and IComparable in general, see this, but in this search method it will not make any difference, or will it?
public static int Search(List a, T target) where T : IComparable
{
…
Dieter Meemken
- 1,937
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4
votes
5 answers
Why is my List.Sort method in C# reversing the order of my list?
I have a list of items in a generic list:
A1 (sort index 1)
A2 (sort index 2)
B1 (sort index 3)
B2 (sort index 3)
B3 (sort index 3)
The comparator on them takes the form:
this.sortIndex.CompareTo(other.sortIndex)
When I do a List.Sort() on the…
Fiona - myaccessible.website
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- 117
4
votes
1 answer
Built-in compare on discriminated unions in f#
In answering this question, I discovered the following behaviour of compare on discriminated unions.
type T = A | B | C | D
compare A B (* val it : int = -1 *)
compare A C (* val it : int = -2 *)
compare A D (* val it : int = -3 *)
I was…
Søren Debois
- 5,598
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4
votes
3 answers
IComparable Does not Implement
I've changed from using IComparable to IComparable However I'm getting the error
'RecordCollection.Artist' does not implement interface member 'System.IComparable.CompareTo(object)'
class Artist : IComparable
I've added a…
Nathan Dean
- 43
- 6
4
votes
1 answer
Benefits of IComparable as Contravariant?
I have very little experience with variance, but after having read quite a bit believe that I understand at least the basic concepts (i.e. variance describes the relationship between the relationship of two types and the relationship of those two…
blf
- 117
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