Graphing a sine/cosine/tan curves in C???

http://www.sci.brooklyn.cuny.edu/~sd.../Program6.html

the link above are specifications to making a so called "simple" program, but how would this be done? especially the graphing of sin, cos and tan?

graph(sin,0.0,10.0,20);

You create a loop that goes from 0.0 to 10.0 (the example in the link I think got it wrong by saying 0.0 to 20.0) in increments of (hi-lo)/(num of points) so:

Code:

void graph( double (*func)(double),double lo,double hi, int number )
{
    double pt;
    double inc = (hi-lo)/number;

    for( pt = lo; lo <= hi; pt += inc )
    {
        /* Call the function for the given pt value, you would need to
        do something with the return value, i.e. store it in an array perhaps
        for later use */
        func(pt);
    }

}

Once you've got all the values stored in an array, you need to normalize them based on the height of the screen display. Then it is a simple matter of going through the stored values in the array and outputting a symbol at the appropriate height based on the normalized value.

how would you print an asterisk based on the height?

probably create a 2d char array:-

Code:

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Then print out the 2d array using a nested for loop.

How you gets the stars into the array will be of course your main problem.