用C语言绘制余弦曲线

#include
#include
#include
#define Pi 3.1415926

void draw()
{
double i;
for(i=0;i<2*Pi;i+=0.01)
putpixel((int)(i*50),(int)(cos(i)*50)+50,12);
}

void main()
{
int gd,gm,ge;
detectgraph(&gd,&gm);
initgraph(&gd,&gm,"d:\\borland\\turboc2");
draw();
getch();
closegraph();
}

修正版：
#include
#include
#include
#define Pi 3.1415926
char y[2];
void draw()
{
double i;
int c;
c=getcolor();
setcolor(2);
line(0,0,0,200);
line(0,100,400,100);
strcpy(y,"y");
outtextxy(1,1,y);
strcpy(y,"0");
outtextxy(1,101,y);
strcpy(y,"x");
outtextxy(380,101,y);
for(i=0;i<2*Pi;i+=0.01)
putpixel((int)(i*50),100-(int)(cos(i)*50),12);
setcolor(c);
}

void main()
{
int gd,gm,ge;
detectgraph(&gd,&gm);
initgraph(&gd,&gm,"d:\\borland\\turboc2");
draw();
getch();
closegraph();
}