Cos

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Syntax

FLOAT cos ( <FLOAT angle> )

Description

Returns the cosine of the specified angle.

This function performs a cosine calculation on a certain angle and returns a value between -1 and 1.

Parameters

FLOAT angle - Angle, in thousandths of degrees. i.e. 75000 = 75º

Returns

FLOAT : The cosine result of the specified angle.

Notes

The angle value used in this function should be in thousandths of degrees, as most angles within Bennu are.

To read about all aspects of trigonometry, you can visit Wikipedia's Trigonometric function page.

Example

Const
    screen_width  = 320;
    screen_height = 200;
    screen_border = 15;
End

Global
    float value;
End

Process Main()
Begin

    // Modes
    set_title("Cosine Graph");
    set_mode(screen_width,screen_height);

    // X axis
    for(x=1;x<=8;x++)
        write( 0,
               screen_border+x*(screen_width-screen_border)/8+3,
               screen_height-1,
               8,
               itoa(x*360/8 )+"^" );
    end
    draw_line(1,screen_height-screen_border,screen_width,screen_height-screen_border);

    // Y axis
    write(0,screen_border-1,20,5,"1");
    write(0,screen_border-1,screen_height/2,5,"0");
    write(0,screen_border-1,screen_height-20,5,"-1");
    draw_line(screen_border,1,screen_border,screen_height-1);

    // Draw tangent
    for(angle=0;angle<360;angle++)
        value=cos(angle*1000)*(screen_height/2-20);
        put_pixel( screen_border+angle*(screen_width-screen_border)/360,
                   screen_height/2-value,
                   rgb(255,255,255) );
        // screen_height/2-value because the screen's origin (0,0) is topleft instead of downleft.
    end

    Repeat
        frame;
    Until(key(_ESC))

End

Used in example: set_title(), set_mode(), write(), draw_line(), cos(), put_pixel(), key()

This will result in something like:

Cos.png
Cosine


Mod_math
Constants PI
Functions Abs()Acos()Asin()Atan()Atan2()Cos()Fgetangle()Fgetdist()Finite()Getdistx()Getdisty()Isinf()Isnan()Nearangle()Pow()Sin()Sqrt()Tan()