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From: Aeden Jameson on 12 Apr 2010 16:53
Suppose I have the class foo

class Foo
{
PropertyOne;
PropertyTwo;
}

and I have a cost calculator class that uses lots of different
information to
calculate a cost.

class CostCalculator
{
public decimal Calculate(Foo foo);
}


I'm struggling with how one would write a linq expression to select
all objects that have the lowest cost. There's no guarantee of
uniqueness. Thanks for your help.

Cheers,
Aeden
From: Andrey on 12 Apr 2010 23:59
First you need create collection or IEnumerable of Foo objects:

List<Foo> Foos = GetFoos(....);

,then

CostCalculator calculator = new CostCalculator ();
var minCost = Foos.Min( s=> calculator(s)).FirstOrDefault();




Aeden Jameson wrote:

Linq Expression for All Objects With Lowest Cost
12-Apr-10

Suppose I have the class foo

class Foo
{
PropertyOne;
PropertyTwo;
}

and I have a cost calculator class that uses lots of different
information to
calculate a cost.

class CostCalculator
{
public decimal Calculate(Foo foo);
}


I am struggling with how one would write a linq expression to select
all objects that have the lowest cost. There is no guarantee of
uniqueness. Thanks for your help.

Cheers,
Aeden

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From: Andrey on 13 Apr 2010 00:02
List<Foo> foos = ... method to create a collection of Foos...

CostCalculator calc = new CostCalculator();
IEnumerable<Foo> minCosts = foos.Min( s=> calc(s));



Aeden Jameson wrote:

Linq Expression for All Objects With Lowest Cost
12-Apr-10

Suppose I have the class foo

class Foo
{
PropertyOne;
PropertyTwo;
}

and I have a cost calculator class that uses lots of different
information to
calculate a cost.

class CostCalculator
{
public decimal Calculate(Foo foo);
}


I am struggling with how one would write a linq expression to select
all objects that have the lowest cost. There is no guarantee of
uniqueness. Thanks for your help.

Cheers,
Aeden

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From: Peter Duniho on 13 Apr 2010 03:34
Aeden Jameson wrote:
> Suppose I have the class foo
>
> class Foo
> {
> PropertyOne;
> PropertyTwo;
> }
>
> and I have a cost calculator class that uses lots of different
> information to
> calculate a cost.
>
> class CostCalculator
> {
> public decimal Calculate(Foo foo);
> }
>
>
> I'm struggling with how one would write a linq expression to select
> all objects that have the lowest cost. There's no guarantee of
> uniqueness. Thanks for your help.

I don't know that there would be code that is expressible solely as a
LINQ expression and which would do that. However, you can certainly
take advantage of LINQ to do something like that.

For example:

IEnumerable<Foo> data = �;
CostCalculator calc = �;

var ordered = from foo in data
select new { Foo = foo, Cost = calc.Calculate(foo) }
orderby Cost;

decimal minCost = ordered.First().Cost;

var least = from fooAndCost in ordered
where fooAndCost.Cost == minCost
select fooAndCost.Foo;

There are other ways you might accomplish the same thing using LINQ, but
the above should work and isn't too inefficient. :)

If the above doesn't address your question, you should try to be more
specific.

Pete
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