Mega Code Archive
Nullable variable
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using System;
using System.Collections.Generic;
using System.Text;
public class Vector {
public double? R = null;
public double? Theta = null;
public double? ThetaRadians {
get {
return (Theta * Math.PI / 180.0);
}
}
public Vector(double? r, double? theta) {
if (r < 0) {
r = -r;
theta += 180;
}
theta = theta % 360;
R = r;
Theta = theta;
}
public static Vector operator +(Vector op1, Vector op2) {
try {
double newX = op1.R.Value * Math.Sin(op1.ThetaRadians.Value)
+ op2.R.Value * Math.Sin(op2.ThetaRadians.Value);
double newY = op1.R.Value * Math.Cos(op1.ThetaRadians.Value)
+ op2.R.Value * Math.Cos(op2.ThetaRadians.Value);
double newR = Math.Sqrt(newX * newX + newY * newY);
double newTheta = Math.Atan2(newX, newY) * 180.0 / Math.PI;
return new Vector(newR, newTheta);
} catch {
return new Vector(null, null);
}
}
public static Vector operator -(Vector op1) {
return new Vector(-op1.R, op1.Theta);
}
public static Vector operator -(Vector op1, Vector op2) {
return op1 + (-op2);
}
public override string ToString() {
string rString = R.HasValue ? R.ToString() : "null";
string thetaString = Theta.HasValue ? Theta.ToString() : "null";
return string.Format("({0}, {1})", rString, thetaString);
}
}
class Program {
public static void Main(string[] args) {
Vector v1 = GetVector("vector1");
Vector v2 = GetVector("vector1");
Console.WriteLine("{0} + {1} = {2}", v1, v2, v1 + v2);
Console.WriteLine("{0} - {1} = {2}", v1, v2, v1 - v2);
Console.ReadKey();
}
public static Vector GetVector(string name) {
Console.WriteLine("Input {0} magnitude:", name);
double? r = GetNullableDouble();
Console.WriteLine("Input {0} angle (in degrees):", name);
double? theta = GetNullableDouble();
return new Vector(r, theta);
}
public static double? GetNullableDouble() {
double? result;
string userInput = Console.ReadLine();
try {
result = double.Parse(userInput);
} catch {
result = null;
}
return result;
}
}
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