輸入角度計算各種三角函數

輸入角度計算各種三角函數的VB程式

數學上的三角函數，如sin30，用VB要如何寫程式碼?

　剛開始，我都以為是 Math.Sin30

但怎麼算都錯。

後來才發現，Sin後面跟的數字不是角度，而是弧度。所以程式碼為

 Math.Sin(30 * (Math.PI / 180))

1) 角度與徑度的轉換

// Calculate the tangent of 30 degrees. angle = 30; radians = angle * (Math.PI/180); result = Math.Tan(radians); Console.WriteLine("The tangent of 30 degrees is {0}.", result); // Calculate the arctangent of the previous tangent. radians = Math.Atan(result); angle = radians * (180/Math.PI); Console.WriteLine("The previous tangent is equivalent to {0} degrees.", angle);

2) 程式

Public Class Form1

    Private Sub Label14_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Label14.Click

        Dim A1 As Double = Val(TextBox1.Text)

        Dim A As Double = A1 * (Math.PI / 180)

        Dim b1 As Double = Math.Sin(A)

        Dim b2 As Double = Math.Cos(A)

        Dim b3 As Double = Math.Tan(A)

        Dim b4 As Double = 1 / b1

        Dim b5 As Double = 1 / b2

        Dim b6 As Double = 1 / b3

        Label2.Text = b1.ToString

        Label3.Text = b2.ToString

        Label5.Text = b3.ToString

        Label7.Text = b4.ToString

        Label10.Text = b5.ToString

        Label12.Text = b6.ToString

    End Sub

   

End Class

3) 執行畫面