Normal distribution and Binomial distribution

Hello !

!()[images/plot.svg]

#include <stdio.h>
#include <math.h>
#include <sketch.h>

#define N 100
#define W 800


double bnc(int n, int k)
{
    double p=1.0;
    if(2 * k > n)
    k = n - k;
    while(k != 0)
    p *= 1.0 * (n--) / (k--);
    return p;
}

double gnd(double x, double variance) {
    return exp(-x*x*N*N/(2*W*W*variance));
}

int main()
{
    int f;
    double high = bnc(N,N/2)/200;
    set_stroke("red");
    for (f=0; f<=N; f++) {
    draw_circle(f*W/N-W/2,bnc(N,f)/high-100,0.5);
    }
    
    set_stroke("blue");
    set_stroke_width(0.5);
    double x;
    double var = N/4;
    for(x=-W;x<=W;x=x+0.1)
    draw_line(x,200*gnd(x,var)-100,x+0.1,200*gnd(x+0.1,var)-100);
    save_sketch("plot.svg");
}