Just another update

This commit is contained in:
Ingy döt Net 2015-02-20 00:35:01 -05:00
parent a25938f123
commit 00a190b0a6
6591 changed files with 94363 additions and 23227 deletions

View file

@ -1,26 +1,22 @@
import std.stdio, std.range;
import std.stdio, std.range, std.traits;
/**
Approximates y(t) in y'(t)=f(t,y) with y(a)=y0 and
t=a..b and the step size h.
*/
void euler(F)(in F f, in double y0,
in double a, in double b, in double h) {
/// Approximates y(t) in y'(t)=f(t,y) with y(a)=y0 and t=a..b and the step size h.
void euler(F)(in F f, in double y0, in double a, in double b, in double h) @safe
if (isCallable!F && __traits(compiles, { real r = f(0.0, 0.0); })) {
double y = y0;
foreach (t; iota(a, b, h)) {
foreach (immutable t; iota(a, b, h)) {
writefln("%.3f %.3f", t, y);
y += h * f(t, y);
}
writeln("done");
"done".writeln;
}
void main() {
/// Example: Newton's cooling law
static newtonCoolingLaw(in double time, in double t) {
return -0.07 * (t - 20);
}
/// Example: Newton's cooling law.
enum newtonCoolingLaw = (in double time, in double t)
pure nothrow @safe @nogc => -0.07 * (t - 20);
euler(&newtonCoolingLaw, 100, 0, 100, 2);
euler(&newtonCoolingLaw, 100, 0, 100, 5);
euler(&newtonCoolingLaw, 100, 0, 100, 10);
euler(newtonCoolingLaw, 100, 0, 100, 2);
euler(newtonCoolingLaw, 100, 0, 100, 5);
euler(newtonCoolingLaw, 100, 0, 100, 10);
}