how can i make graphs with C?

i have an exercise here to be passed in school about creating graphs such as line and arcs... how can i start making one? i really dont know how to make one.

here are some details..

1. i need to choose what graph should i make. wheter a line or an arc.

1.1 if i choose line, i need to input 2 coordinates. (eg. (70,4), (10,15)

2. the range of x axis is 80, the range of y axis is 20...

3. the upper left corner is the origin (0,0). the positive x axis is to the right, the positive y axis is to downwards.

4. if i choose arc, the following formula is to be followed : y^2 = 4ax

if you want to help me out you can email me at: <<snipped>>

thx in advance to those who can help. btw, the submission is on the 19th of january. i barely have 20 days to make the program. thx again. :D

You didn't say what platform. If it's Windows, check out Charles Petzold's book "Programming Windows Fifth Edition". It will tell you EXACTLY how to do what you need to do.

Todd

Well which graphics library you choose depends a great deal on which Operating system and compiler you use.
So can you tell us a bit of background to help narrow the suggestions.

Quote:

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Originally Posted by Salem

Well which graphics library you choose depends a great deal on which Operating system and compiler you use.
So can you tell us a bit of background to help narrow the suggestions.

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i use windows vista, im using the turbo c because some fcns can't be used in c++... i always get error when compiling in my devc++...

Turbo C is horribly old and poor.
If you can't use something in Dev-C++, it's probably because you're doing it wrong.

Using Turbo C on Windows Vista is one way to horribly screw up your perception of C programming.

This is just a Christmas card type of thing, from DOS days. The screen ratio is all screwy with Windows and the newer/bigger monitors, but anyway.

It shows in the sine-wave portion of it, one way to draw with Turbo C, on the screen, using nothing from Windows (because Windows was still a twinkle in Xerox's Parc Research Center's eye, at that time.

Can you show an example of what you want the final output to look like, and what have you got so far?

Code:

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#include <graphics.h>
#include <conio.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <dos.h>

const int pi=3.1415927;          /*part of the initial sinewave drawing */

void main()
  {
  void drawstar();
  int graphdriver, graphmode, errorcode, i;
  double swing, width, crest, ypos;

  graphdriver = DETECT;
  initgraph(&graphdriver, &graphmode, "C:\\TC\\BGI");
  errorcode = graphresult();
  if (errorcode != grOk)
    {
    printf("Graphics System Error: %s\n",grapherrormsg (errorcode));
    exit(1);
    }
  ypos = getmaxy() /2;
  crest = getmaxy() /4;
  width = getmaxx();
  for (i=0; i<width; i++)
    {
    swing=crest*sin(10*pi*i/width);
    putpixel(i, ypos+swing, RED);
    putpixel(i, ypos-swing, BLUE);
    }
  sleep(2);
  drawstar();
  closegraph();
  }
void drawstar()
  {
  cleardevice();  //NOT clrscr();
  setcolor(BLACK);
  int x,y;
  int half1[] = {120,20, 106,40, 80,40, 93,60, 80,80, 106,80, 120,100, 134,80, 160,80, 147,60, 160,40, 134,40, 120,20};
  fillpoly(13, half1);
  setcolor(BLUE);
  settextstyle(TRIPLEX_FONT, HORIZ_DIR, 2);
  outtextxy(190,20, "... and a bright star shone in the East");
  setcolor(RED);
  settextstyle(GOTHIC_FONT, HORIZ_DIR, 8);
  outtextxy(33,30, "Merry Christmas"); 
  settextstyle(GOTHIC_FONT, HORIZ_DIR, 6);
  outtextxy(95,120, "and Happy Holidays");
/*  outtextxy(190,90, "to Everyone at"); */
/*  settextstyle(GOTHIC_FONT, HORIZ_DIR, 8); */
/*  outtextxy(30,120, "  This  Home"); */
  getch();
  }

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> i use windows vista, im using the turbo c because some fcns can't be used in c++
So you're another person who's bought a Ferrari, and replaced the engine with an elastic band.

If I told you that no matter how many processors your machine has, and how many GB of memory you have, and how long your filenames can be, that you're restricting yourself to
- 1 processor
- 640K (Yes, K, not M or G) bytes of memory
- 8.3 filenames.

Plus, any graphics you might get will be limited to probably at most 800x600 and 256 colours.

Are you going to reconsider your use of that stone-age compiler.


> ... i always get error when compiling in my devc++...
Perhaps if you posted code and error messages, we could tell you what to do about it.
For starters, there is no graphics.h, and the BGI graphical API is dead.

If you get dev-c++, the first thing you do is download the libsdl "devpak", and then get yourself over to www.libsdl.org and read some tutorials.

Quote:

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If I told you that no matter how many processors your machine has, and how many GB of memory you have, and how long your filenames can be, that you're restricting yourself to
- 1 processor
- 640K (Yes, K, not M or G) bytes of memory
- 8.3 filenames.

---

Lol, that really is awful.

Definitely have a go at getting DevCpp to work. SDL is quite simple for doing 2d graphics with, and the newer versions of DevCpp have a package manager that can do all the setup for you.

[edit]Actually now I remember: I couldent get devcpp to work on vista either so I just started using MSVC++ instead until I switched to Ubuntu. I really don't like vista. XP is just so much better. [/edit]

thanks for all your replies... sorry that im not so used in c language. i just started about a month ago and i dont learn anything at all from my professors. they just keep giving us work not backing us with important information on how to do it.. sorry to bother all of you who are masters in this... hope you understand my situation... all what i was trying to do was to gain some information on how to make my work done but it seems i didnt get any help coz u all just gave your comments and not helping with my problem... you all have the mind but it is all you've got..

>dont reply anymore with useless comments.... they wont help me either..

Quote:

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Originally Posted by Elysia

Turbo C is horribly old and poor.
If you can't use something in Dev-C++, it's probably because you're doing it wrong.

---

i know im not doing it wrong.. it does not compile because some functions can't be read by cpp... get it master elysia?

Quote:

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all what i was trying to do was to gain some information on how to make my work done but it seems i didnt get any help coz u all just gave your comments and not helping with my problem.

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The comments are intended to help you with your problem. Namely, they suggest that:

1. You use a newer compiler and IDE.
2. You download an IDE package with the library you need.
3. You search for the information on getting started yourself at the library's website.

Quote:

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i know im not doing it wrong.. it does not compile because some functions can't be read by cpp.

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Which functions might they be? If you really are such a beginner, how do you know that what you think you know is correct?

Quote:

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Originally Posted by Salem

Are you going to reconsider your use of that stone-age compiler.

---

I fired up Turbo C a few months ago just for giggles. A bunch of good old memories came flooding right back. It's sad to see good products become obsolete, although that's the way of things.

> i know im not doing it wrong.. it does not compile because some functions can't be read by cpp.
Until you post some of YOUR code, there isn't much anyone else can do, irrespective of whichever compiler you're using.

Quote:

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Originally Posted by anchee123

i know im not doing it wrong.. it does not compile because some functions can't be read by cpp... get it master elysia?

---

Post your code and we'll see if we can get it work in Dev-C++ or Visual Studio or whatever and we'll see who's "right."

If you don't understand what the professors are teaching go to their office after class and ask for clarification, or ask someone else from your class. Opening and reading, and re-reading the book is a great start. You're paying for college so you better get your money's worth.

Err actually, now i remember better it was gcc that had compatibility problems with vista, not DevCpp itself. Compiling with g++ worked fine.

Anchee: What functions is it that are not compatible with c++? Maybe you could find, or create your own alternatives. People here arent going to be able to help much unless you are more specific with your problem and/or post your code.

Quote:

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Originally Posted by anchee123

i know im not doing it wrong.. it does not compile because some functions can't be read by cpp... get it master elysia?

---

Of course you're doing something wrong - otherwise it would work. :)

You are walking too proudly in the earth, my friend. Programming isn't about YOU, because you WILL make thousands of mistakes before you learn to program well, I promise.

We all did.

The advice you were given was excellent, but may not be relevant to you. For example, when I took my C class, the instructor told us which compiler was REQUIRED, period. Changing compiler's was not an option - neither was using a library that wasn't specified by the instructor.

In the long run, you should indeed move to a more modern compiler and use libraries to simplify your programming, and improve the final product. To suggest that you can't draw a line or arc graph in Turbo C without special libraries is simply wrong, and:

** Run time is not an issue - the graph will be drawn in the blink of an eye
** The number of processors used is not an issue. One is plenty!
** The amount of memory available is not an issue - there's more than enough for a graph.

Anchee, you need to post up all the details, an example of input for this, and what you've decided for your type of graph. Also, whatever code you have attempted, whether working or not.

ok then here's the whole thing...
1. Problem Statement
Create a program which draws a given graph to the standard output using an ASCII character.
2 .Overall Description
AscGraph is short for ASCII Graphics Software. It is a command line executable program which
draws graphs in the standard output of the console using printable ASCII characters.

3 General Requirements
3.1 Development Environment
The program must be developed under Linux O.S. The IDE or editor can be any of your choice.
3.2 Testing Environment
The program will be tested under the following testing environment:
Field Type: Environment / Version
Operating System: Linux
Distribution: Ubuntu
Shell bash: (KDE konsole)
gcc: 3.4

4.1 Program name
The name of the executable file for this program is:
ascgraph
The code shall compile successfully with –Wall –Werror gcc options.
4.2 Program Syntax
./ascgraph
4.3 External Interfaces
The user is prompted with several questions. The first question must be to enter the graph type. The succeeding questions depend on the graph type entered by the user.

.... the next thing will show the supported graphs..

ok then here's the whole thing...
1. Problem Statement
Create a program which draws a given graph to the standard output using an ASCII character.
2 .Overall Description
AscGraph is short for ASCII Graphics Software. It is a command line executable program which
draws graphs in the standard output of the console using printable ASCII characters.

3 General Requirements
3.1 Development Environment
The program must be developed under Linux O.S. The IDE or editor can be any of your choice.
3.2 Testing Environment
The program will be tested under the following testing environment:
Field Type: Environment / Version
Operating System: Linux
Distribution: Ubuntu
Shell bash: (KDE konsole)
gcc: 3.4

4.1 Program name
The name of the executable file for this program is:
ascgraph
The code shall compile successfully with –Wall –Werror gcc options.
4.2 Program Syntax
./ascgraph
4.3 External Interfaces
The user is prompted with several questions. The first question must be to enter the graph type. The succeeding questions depend on the graph type entered by the user.

.... the next post will show the supported graphs..

here's the pdf...

pls open the pdf so you can help me out... sorry for the useless things i said in my previous posts... thank you... i just felt bad because still now i cant finish the machine problem...

Quote:

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Originally Posted by anchee123

i use windows vista, im using the turbo c because some fcns can't be used in c++... i always get error when compiling in my devc++...

---

And yet your assignment is to be done on the Linux platform using gcc.

Quote:

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Originally Posted by anchee123

pls open the pdf so you can help me out... sorry for the useless things i said in my previous posts... thank you... i just felt bad because still now i cant finish the machine problem...

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Anchee, I've looked at the pdf, and it's not to be done in Turbo C, so drop Turbo C please, immediately!

Do you have a gcc compiler? That's what you'll need (be sure it's the right version, too).

Do you have any code at all yet? Post it up, working or not. This is much more than just coding a program. There is a flow chart to be done, and other paperwork as well.

Put it into high gear now, Anchee, time is short.

Quote:

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Originally Posted by Adak

Anchee, I've looked at the pdf, and it's not to be done in Turbo C, so drop Turbo C please, immediately!

Do you have a gcc compiler? That's what you'll need (be sure it's the right version, too).

Do you have any code at all yet? Post it up, working or not. This is much more than just coding a program. There is a flow chart to be done, and other paperwork as well.

Put it into high gear now, Anchee, time is short.

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i have a gcc compiler... here's my code but it still lacks alot... hope u can help me with this...

Code:

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#include <stdio.h>
#include <conio.h>
#define LENGTH 80
#define HEIGHT 20
#define CHARACTER 'X'

int main()
{
int x1, y1, x2, y2;
system("CLS");

printf("x1: ");
scanf("%d", &x1);
printf("y1: ");
scanf("%d", &y1);
printf("x2: ");
scanf("%d", &x2);
printf("y2: ");
scanf("%d", &y2);
system("CLS");

gotoxy(x1,y1);
printf("%c", CHARACTER);
gotoxy(x2,y2);
printf("%c", CHARACTER);


}

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