// various
constant kPI                 :=  3.1415926535898;
constant kDeg2Rad            :=  0.01745329251994;
constant kRad2Deg            := 57.29577951308;

// OS National Grid
constant kOS_E0   :=  400000.0;		// offset of false origin
constant kOS_N0   := -100000.0;		// offset of false origin
constant kOS_Lat0 :=  0.855211357;	// Latitude of false origin (49degN)
constant kOS_Lon0 := -0.034906586;	// Longitude of false origin (2degW)
constant kOSf0    := 0.9996012717;	// scale on central meridian
constant kAiryA   := 6377563.396;	// Airy ellipsoid
constant kAiryB   := 6356256.910;
constant kAiryRF  := 299.3249646;	// 1/flattening

constant kAiryAxF0 := 6375020.480989;	// a * F0
constant kAiryBxF0 := 6353722.490488;	// b * F0
constant kAiryN    := 0.001673220250;	// (a - b)/(a + b)
constant kAiryN2   := 0.00000279966600501;	// n^2
constant kAiryN3   := 0.000000004684457852819;	// n^3
constant kAiryES   := 0.006670539762;	// eccentricty squared (a^2 - b^2) / a ^2

constant kOSGrid500 := '["S","T","N","O","H","J"];
constant kOSGrid100 := '["V","W","X","Y","Z", "Q","R","S","T","U", "L","M","N","O","P", "F","G","H","J","K", "A","B","C","D","E"];

constant kUTM_E0   :=  500000.0;		// offset of false origin
constant kUTM_N0   := 10000000.0;		// offset of false origin (S hemisphere)

constant kUTM_f0   := 0.9996;
constant kUTM_A    := 6378388.000;
constant kUTM_B    := 6356911.946;
constant kUTM_RF   := 297.000;

constant kUTM_AxF0 := 6375836.644800;	// a * F0
constant kUTM_BxF0 := 6354369.181222;	// b * F0

