Есть вот такой код, который считает метод прогонки
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8"/>
<script type="application/javascript">
function f1(t)
{
return 1-t;
}
function f2(t)
{
return t;
}
function f3(t)
{
return (-1/6)*t*(t-1)*(t-2);
}
function f4(t)
{
return (1/6)*t*(t-1)*(t+1);
}
function f(x)
{
return x*Math.exp(-x);
}
var left=0,right=2;
var x1=[],y1=[],a=[],b=[],c=[],d=[],u=[],v=[],y2=[],x=[];
var N=10,h=(right-left)/N,i=-1;
for(var x1=left;x1<=right;x1+=h)
y1[++i] = -2*Math.exp(-x1)+Math.exp(-x1)*x1;
a[1]=1;
a[N]=1;
b[1]=0;
b[N]=0;
c[1]=0;
c[N]=0;
d[1]=y1[0];
d[N]=y1[y1.length-1];
i=-1;
for(var x1=left;x1<=right;x1+=h)
y1[++i] = f(x1);
alert(y1);
for(var i=2;i<N;i++)
{
a[i]=4;
b[i]=1;
c[i]=1;
d[i]=6*(y1[i-1]-2*y1[i]+y1[i+1])/h;
}
u[1] = d[1]/a[1];
v[1]=-b[1]/a[1];
for(i=2;i<N;i++)
{
u[i]=(d[i]-c[i]*u[i-1])/(c[i]-v[i-1]+a[i]);
v[i]=-b[i]/(c[i]*v[i-1]+a[i]);
}
for(i=0;i<=N;i++)
x[i] = i*h+left;
alert(x);
v[N]=0;
u[N]=-1;
y2[N]=d[N];
for(i=N-1;i>-1;i--)
{
y2[i]=v[i]*y2[i+1]+u[i];
}
var s=[];
var count=-1;
for(var i=0;i<N;i++)
{
s[i] = 0;
for(var xx=x[i];xx<=x[i+1];xx+=0.01)
{
t = (xx-x[i])/h;
s[++count] = y1[i]*f1(t)+y1[i+1]*f2(t)+y2[i]*h*f3(t)+y2[i+1]*h*f4(t);
}
}
alert(s);
function draw() {
var canvas = document.getElementById('canvas');
if (canvas.getContext) {
var ctx = canvas.getContext('2d');
ctx.beginPath();
ctx.moveTo(0, y1[0]);
for(i=1;i<y1.length;i++)
ctx.lineTo(100*i,100*Math.abs(y1[i]));
//ctx.closePath();
ctx.strokeStyle = '#ff0000';
ctx.stroke();
ctx.beginPath();
ctx.moveTo(0, s[0]);
for(i=1;i<=s.length;i++)
ctx.lineTo(5*i,100*Math.abs(s[i]));
ctx.strokeStyle = '#00ff00';
ctx.stroke();
}
}
</script>
</head>
<body onload="draw();">
<canvas id="canvas" width="1000" height="400" border="black"></canvas>
</body>
</html>
