What is the lightest collection for store these values? [closed]

Question

I have many objects (such as 10.000, more or less). Every object has3 values :

1. Index (decimal, such as 0,0 <= X <= 100.000,9);
2. A Latitude value;
3. A Longitude value;

and I need to perform some search due to the Index value. Which will be the light approch to this? List<MyObject>? I know there are hashtable, but only for 2 values...

I read these values from a .csv file and I'll store it on application. WebForm, .NET 4.5.

Answer 1

The very lightest approach in terms of memory use is to put these into a struct, and hold them in an array of such structs. From what you say, you can't really pack data any tighter than that: two doubles and a decimal will occupy 32 bytes per entry, and the array of structs does not add any per-item overhead on top of this.

Having said that, this will slow down your coding and might save too little to matter in practice.