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Just another update

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Ingy döt Net 2015-02-20 00:35:01 -05:00
parent a25938f123
commit 00a190b0a6
6591 changed files with 94363 additions and 23227 deletions
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42
Task/Resistor-mesh/D/resistor-mesh.d
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@ -3,42 +3,44 @@ import std.stdio, std.traits;
enum Node.FP differenceThreshold = 1e-40;
struct Node {
alias real FP;
alias FP = real;
enum Kind : size_t { free, A, B }
FP voltage = 0.0;
private Kind kind = Kind.free;
@property Kind fixed() const pure nothrow { return kind; }
/*const*/ private Kind kind = Kind.free;
// Remove kindGet once kind is const.
@property Kind kindGet() const pure nothrow @nogc {return kind; }
}
Node.FP iter(size_t w, size_t h)(ref Node[w][h] m) pure nothrow {
Node.FP iter(size_t w, size_t h)(ref Node[w][h] m) pure nothrow @nogc {
static void enforceBoundaryConditions(ref Node[w][h] m)
pure nothrow {
pure nothrow @nogc {
m[1][1].voltage = 1.0;
m[6][7].voltage = -1.0;
}
static Node.FP calcDifference(in ref Node[w][h] m,
ref Node[w][h] d) pure nothrow {
ref Node[w][h] d) pure nothrow @nogc {
Node.FP total = 0.0;
foreach (i; 0 .. h)
foreach (j; 0 .. w) {
foreach (immutable i; 0 .. h) {
foreach (immutable j; 0 .. w) {
Node.FP v = 0.0;
{
size_t n = 0;
if (i != 0) { v += m[i - 1][j].voltage; n++; }
if (j != 0) { v += m[i][j - 1].voltage; n++; }
if (i < h-1) { v += m[i + 1][j].voltage; n++; }
if (j < w-1) { v += m[i][j + 1].voltage; n++; }
if (i != 0) { v += m[i - 1][j].voltage; n++; }
if (j != 0) { v += m[i][j - 1].voltage; n++; }
if (i < h - 1) { v += m[i + 1][j].voltage; n++; }
if (j < w - 1) { v += m[i][j + 1].voltage; n++; }
v = m[i][j].voltage - v / n;
}
d[i][j].voltage = v;
if (m[i][j].fixed == Node.Kind.free)
if (m[i][j].kindGet == Node.Kind.free)
total += v ^^ 2;
}
}
return total;
}
@ -49,16 +51,16 @@ Node.FP iter(size_t w, size_t h)(ref Node[w][h] m) pure nothrow {
enforceBoundaryConditions(m);
if (calcDifference(m, difference) < differenceThreshold)
break;
foreach (i, const(Node[]) di; difference)
foreach (j, ref const(Node) dij; di)
foreach (immutable i, const di; difference)
foreach (immutable j, const ref dij; di)
m[i][j].voltage -= dij.voltage;
}
Node.FP[EnumMembers!(Node.Kind).length] cur = 0.0;
foreach (i, const(Node[]) di; difference)
foreach (j, ref const(Node) dij; di)
cur[m[i][j].fixed] += dij.voltage *
(!!i + !!j + (i < h-1) + (j < w-1));
foreach (immutable i, const di; difference)
foreach (immutable j, const ref dij; di)
cur[m[i][j].kindGet] += dij.voltage *
(!!i + !!j + (i < h-1) + (j < w-1));
return (cur[Node.Kind.A] - cur[Node.Kind.B]) / 2.0;
}
@ -72,5 +74,5 @@ void main() {
mesh[1][1] = Node( 1.0, Node.Kind.A);
mesh[6][7] = Node(-1.0, Node.Kind.B);
writefln("R = %.19f", 2 / iter(mesh));
writefln("R = %.19f", 2 / mesh.iter);
}