Csharp/CSharp Tutorial/Data Type/double Calculation
Содержание
- 1 Calculate the radius of a circle given its area using Math function
- 2 Compute the area of a circle with "double"
- 3 Do calculation with double value
- 4 double base Fahrenheit and Celsius (Centigrade) Scales
- 5 doubles and arithmetic operators
- 6 Implement the Pythagorean Theorem
- 7 Use the while statement to implement Newton"s method for finding the square root
Calculate the radius of a circle given its area using Math function
<source lang="csharp">using System;
class MainClass {
public static void Main() {
Double r;
Double area;
area = 10.0;
r = Math.Sqrt(area / 3.1416);
Console.WriteLine("Radius is " + r);
}
}</source>
Radius is 1.78412203012729
Compute the area of a circle with "double"
<source lang="csharp">using System;
class Circle {
public static void Main() {
double radius;
double area;
radius = 10.0;
area = radius * radius * 3.1416;
Console.WriteLine("Area is " + area);
}
}</source>
Area is 314.16
Do calculation with double value
<source lang="csharp">using System; using System.Collections.Generic; using System.Text; class Program {
static void Main(string[] args) {
double firstNumber, secondNumber;
string userName;
userName = "AAA";
firstNumber = Convert.ToDouble("1.1");
Console.WriteLine("Now give me another number:");
secondNumber = Convert.ToDouble(1.2);
Console.WriteLine("The sum of {0} and {1} is {2}.", firstNumber,
secondNumber, firstNumber + secondNumber);
Console.WriteLine("The result of subtracting {0} from {1} is {2}.",
secondNumber, firstNumber, firstNumber - secondNumber);
Console.WriteLine("The product of {0} and {1} is {2}.", firstNumber,
secondNumber, firstNumber * secondNumber);
Console.WriteLine("The result of dividing {0} by {1} is {2}.",
firstNumber, secondNumber, firstNumber / secondNumber);
Console.WriteLine("The remainder after dividing {0} by {1} is {2}.",
firstNumber, secondNumber, firstNumber % secondNumber);
}
}</source>
double base Fahrenheit and Celsius (Centigrade) Scales
<source lang="csharp">using System; public class MainClass {
public static void Main(string[] args) {
double dFahr = 123.123;
double dCelsius;
dCelsius = (dFahr - 32.0) * (5.0 / 9.0);
Console.WriteLine("Temperature in degrees Celsius = " + dCelsius);
}
}</source>
doubles and arithmetic operators
<source lang="csharp">class MainClass {
public static void Main()
{
System.Console.WriteLine("10d / 3d = " + 10d / 3d);
System.Console.WriteLine("10.0 / 3.0 = " + 10.0 / 3.0);
double doubleValue1 = 10;
double doubleValue2 = 3;
System.Console.WriteLine("doubleValue1 / doubleValue2 = " + doubleValue1 / doubleValue2);
}
}</source>
10d / 3d = 3.33333333333333 10.0 / 3.0 = 3.33333333333333 doubleValue1 / doubleValue2 = 3.33333333333333
Implement the Pythagorean Theorem
<source lang="csharp">using System; class MainClass {
public static void Main() {
double s1 = 3.0;
double s2 = 4.0;
double hypot;
hypot = Math.Sqrt(s1*s1 + s2*s2);
Console.WriteLine("Hypotenuse is " + hypot);
}
}</source>
Hypotenuse is 5
Use the while statement to implement Newton"s method for finding the square root
<source lang="csharp">using System; public class MainClass {
public static void Main( ) {
double epsilon = 1.0e-9;
double guess = 11.0;
double value = 2;
double result = ((value / guess) + guess) / 2;
Console.WriteLine( "Guess Value = {0}", guess );
Console.WriteLine( "Result Value = {0}", result );
while( Math.Abs(result - guess) > epsilon ) {
guess = result;
result = ((value / guess) + guess) / 2;
Console.WriteLine( "Guess Value = {0}", guess );
Console.WriteLine( "Result Value = {0}", result );
}
Console.WriteLine("The approx sqrt of {0} is {1}", value, result );
}
}</source>
Guess Value = 11 Result Value = 5.59090909090909 Guess Value = 5.59090909090909 Result Value = 2.97431633407243 Guess Value = 2.97431633407243 Result Value = 1.82336988350512 Guess Value = 1.82336988350512 Result Value = 1.46012001740362 Guess Value = 1.46012001740362 Result Value = 1.41493521627426 Guess Value = 1.41493521627426 Result Value = 1.41421374640426 Guess Value = 1.41421374640426 Result Value = 1.41421356237311 Guess Value = 1.41421356237311 Result Value = 1.41421356237309 The approx sqrt of 2 is 1.41421356237309
