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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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18
Task/Matrix-arithmetic/D/matrix-arithmetic.d
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@ -1,32 +1,30 @@
import std.algorithm, std.range, std.traits, permutations2,
permutations_by_swapping1;
auto prod(Range)(Range r) /*pure*/ nothrow {
return reduce!q{a * b}(cast(ForeachType!Range)1, r);
auto prod(Range)(Range r) nothrow @safe @nogc {
return reduce!q{a * b}(ForeachType!Range(1), r);
}
T permanent(T)(in T[][] a) /*pure nothrow*/
T permanent(T)(in T[][] a) nothrow @safe
in {
foreach (const row; a)
assert(row.length == a[0].length);
assert(a.all!(row => row.length == a[0].length));
} body {
auto r = a.length.iota;
T tot = 0;
foreach (sigma; r.array.permutations)
foreach (const sigma; r.array.permutations)
tot += r.map!(i => a[i][sigma[i]]).prod;
return tot;
}
T determinant(T)(in T[][] a) /*pure nothrow*/
T determinant(T)(in T[][] a) nothrow
in {
foreach (const row; a)
assert(row.length == a[0].length);
assert(a.all!(row => row.length == a[0].length));
} body {
immutable n = a.length;
auto r = n.iota;
T tot = 0;
//foreach (sigma, sign; n.spermutations) {
foreach (sigma_sign; n.spermutations) {
foreach (const sigma_sign; n.spermutations) {
const sigma = sigma_sign[0];
immutable sign = sigma_sign[1];
tot += sign * r.map!(i => a[i][sigma[i]]).prod;