A piece of art

What exactly is a piece of art? Is this a piece of art?

 

//Exercise 9

#include<stdio.h>
#include<windows.h>
#include<gl/gl.h>
#include<gl/glut.h>

float index[100]={0}, MA[100]={0}, bar_width, bar_height, height_scale, index_max;
int N, M;

int main(int argc, char**argv)
{
 void userinput(int*, int*); //asking for user input
 void calculateMA(int, int, float[], float[]); //calculate moving average
 void printMA(int, int, float[], float[]); //
 float compare_index(float[], int); // find the index with max value (to calculate height scale)
 void graph(void); //draw axis, title, legend and bar chart
 
 glutInit(&argc, argv);
 glutInitDisplayMode(GLUT_RGBA);
 glutInitWindowPosition(10, 50);
 glutInitWindowSize(700, 350);
 glutCreateWindow("Moving Average for a 15-Day Series");

 userinput(&N, &M);
 calculateMA(N, M, index, MA);
 printMA(N, M, index, MA);
 index_max = compare_index(index, N);

 bar_width = 0.8/N;
 height_scale = 1.6/index_max;
 
 glutDisplayFunc(graph);
 
 glutMainLoop();
 
 return 0;
}

//---------------------------------graph function----------------------------------------------------------
void graph(void)
{
 void MA_lines(int, int, float, float, float[]); //draw moving average lines and dots
 int i, j;
 float red, green, blue, x;
 char title[40] = {"Moving Averages for a N days series"};
 char MAvg[3][30]= {{"3-day moving average"},{"4-day moving average"},{"5-day moving average"}}; //Take note

 glClearColor(1.0, 0.5, 1.0, 0.0);
 glClear(GL_COLOR_BUFFER_BIT);

 //write title
 glColor3f(0.0, 0.0, 0.0);
 glLineWidth(3.0);

 glRasterPos2f(-0.8, 0.85);
 for (i=0; i<40; i++)
  glutBitmapCharacter(GLUT_BITMAP_TIMES_ROMAN_24, title[i]);

 //draw axis
 glBegin(GL_LINE_STRIP);
  glVertex2f(-0.8, 0.8);
  glVertex2f(-0.8, -0.8);
  glVertex2f(0.8, -0.8);
 glEnd();

 //draw legend lines
 glLineWidth(1.0);
 glPointSize(3.0);
 
 for (i=0, x=-0.9; i<3; i++,x=x+0.6)
 {
  if (i == 0)
  { red=1.0; green=0.0; blue=0.0; }
  else if (i == 1)
  { red=0.0; green=1.0; blue=0.0; }
  else if (i == 2)
  { red=0.0; green=0.0; blue=1.0; }
 
  glColor3f(red, green, blue);
 
  glBegin(GL_LINES);
   glVertex2f(x, -0.9);
   glVertex2f(x+0.05, -0.9);
  glEnd();

  glBegin(GL_POINTS);
   glVertex2f(x+0.025, -0.9);
  glEnd();

 //write legend words
 glColor3f(0.0, 0.0, 0.0);
 glRasterPos2f(x+0.1 , -0.9);
 for (j=0; j<30; j++)
  glutBitmapCharacter(GLUT_BITMAP_8_BY_13, MAvg[i][j]);
 }

 //draw barchart
 glColor3f(1.0, 1.0, 0.5);
 glLineWidth(3.0);
 
 for(i=1, x=-0.8+bar_width; i<=N; i++,x=x+2*bar_width)
 {
  glPolygonMode(GL_FRONT, GL_FILL);
  glRectf(x,-0.79, x+bar_width, -0.8+height_scale*index[i]);
 }

 //draw moving average lines
 for (i=1; i<=3; i++)
 {
  if (i == 1)
  { red=1.0; green=0.0; blue=0.0; }
  else if (i == 2)
  { red=0.0; green=1.0; blue=0.0; }
  else if (i == 3)
  { red=0.0; green=0.0; blue=1.0; }

 MA_lines(N, i, bar_width, height_scale, MA);
 }

 glFlush();

}

//-------------------------------MA_lines function-----------------------------------

void MA_lines(int N, int M, float bar_width, float height_scale, float MA[] )
{
 int i;
 float x;
 //draw MA lines
 glColor3f(1.0, 0.0, 0.0);
 glLineWidth(1.0);
 glBegin(GL_LINE_STRIP);
  for(i=M, x=-0.8+(2*M-0.5)*bar_width; i<=N; i++,x=x+2*bar_width)
  {
   glVertex2f(x,-0.8+height_scale*MA[i]);
  }
 glEnd();
 
 //draw MA points
 glPointSize(3.0);
 glBegin(GL_POINTS);
  for(i=M, x=-0.8+(2*M-0.5)*bar_width; i<=N; i++,x=x+2*bar_width)
  {
   glVertex2f(x,-0.8+height_scale*MA[i]);
  }
 glEnd();
 glFlush();
}

//--------------------------user input function---------------------------------------
void userinput(int *N, int*M)
{
 do
  {
   printf("Enter number of days of index supplied: ");
   scanf("%d", N);
   printf("Enter the number of days of moving average required: ");
   scanf("%d", M);
   printf("\n");
  } while (*N<*M);
}

//-------------------------calculate MA function----------------------------------------
void calculateMA(int N, int M, float a[], float b[])
{
 int i, j;

 for (i = 1; i<=N; i++)
 {
  printf("Enter index of day %d: ", i);
  scanf("%f", &a[i]);
 }
 
 for (i = M; i<=N; i++)
 {
  for (j = 0; j < M; j ++)
  {
   b[i] = b[i] + a[i-j];
  }
  b[i] = b[i]/M;
 }
}

//------------------------------printMA function---------------------------------------
void printMA(int N, int M, float a[], float b[])
{
 int i;
 printf("\n  Day     Index     %d-day MA\n", M);
 printf("------------------------------\n");
 for (i = 1; i<=N; i++)
 {
  printf("   %d   %8.1f      %6.1f\n", i, a[i], b[i]);
 }
 printf("\n");
}

//---------------------------compare_index function--------------------------------------------
float compare_index(float index[], int N)
{
 int i, max_value = index[1];
 for (i=2; i<=N; i++)
 {
  if (max_value < index[i])
  max_value = index[i];
 }
 
 return max_value;
}

 

I spent days trying to work out how to solve this problem. I write every single word of this code myself. And in the end, I get the computer to draw a graph for me.

To me, this a piece of art.

PS. This piece of art got 缺陷美， because it is incomplete. There's room for improvement.

PPS. Programming is simple. To be good in programming, there is a secret: You just become one with the computer! You think like a computer, act like a computer, be a computer. I think this secret comes too late to some pple, but it applies to everything else - drving, cooking, maths whatever. Just use your imagination. =)

PPPS. If you think what I've written is jus crap, remember, you are in a forbbiden section of my world. WHAT ARE YOU DOING HERE?!