filterByDistance.linq

var pabs = new []
{
	new { 
			id = 0, name = "Green Way", 	
			address= "Льва Толстого вул., 31", 	
			lat = 48.62079866700977, 
			lng = 22.291045737400175
		},
	new { 
			id = 1, name = "R4", 			
			address= "Свободи просп., 3",		
			lat = 48.61990841762924, 
			lng = 22.288635653378783
		},
	new { 
			id = 3, name = "Акваріум", 	
			address= "Льва Толстого вул., 44",		
			lat = 48.6215821602211, 
			lng = 22.289350484427537
		}
		,
	new { 
			id = 4, name = "готель Ужгород", 	
			address= "",		
			lat = 48.62115128530497, 
			lng = 22.28676487962975
		}
		,
	new { 
			id = 5, name = "Спортбар", 	
			address= "Капушанська вул., 26",		
			lat = 48.61873629642148, 
			lng = 22.289441813611752
		}
}.AsQueryable().Dump("Pabs");

var p1 = new {lat = 48.615672658147666, lng = 22.290330284830027};
var d = 0.5;

var selectedPubs = 
	from p2 in pabs
	let R = 6371// Radius of the Earth in km
	let dLat = (p2.lat - p1.lat) * Math.PI / 180
	let dLon = (p2.lng - p1.lng) * Math.PI / 180
	let a = Math.Sin(dLat / 2) * Math.Sin(dLat / 2) + Math.Cos(p1.lat * Math.PI / 180) * Math.Cos(p2.lat * Math.PI / 180) * Math.Sin(dLon / 2) * Math.Sin(dLon / 2)
	let c = 2 * Math.Atan2(Math.Sqrt(a), Math.Sqrt(1 - a))
	let distance = R * c
	where distance<=d
	select new {p2.id, p2.name, p2.address, p2.lat,p2.lng, distance = distance>1?distance.ToString("0.0") + " км":(distance*1000).ToString("0")+" м"};
	
selectedPubs.OrderBy(x=>x.distance).Dump();