2016 Update

Task/Matrix-multiplication/PowerShell/matrix-multiplication.psh

@@ -1,31 +1,38 @@
-function array-mult($A, $B) {
-    $C = @()
-    if($n -gt 0) {
-        $C = 0..($n-1)| foreach{@(0)}
-        0..($n-1)| foreach{
-            $i = $_
-            $C[$i] = 0..($n-1)| foreach{
-                $j = $_
-                $((0..($n-1) | foreach{
-                    $k = $_
-                    $A[$i][$k]*$B[$k][$j]
-                } | measure -Sum).Sum)
+function multarrays($a, $b) {
+    $c = @()
+    if($a -and $b) {
+        $n = $a.count - 1
+        $m = $b[0].count - 1
+        $c = @(0)*($n+1)
+        foreach ($i in 0..$n) {
+            $c[$i] = foreach ($j in 0..$m) {
+                $sum = 0
+                foreach ($k in 0..$n){$sum += $a[$i][$k]*$b[$k][$j]}
+                $sum
             }
         }
     }
-    $C
+    $c
 }
 function show($a) {
-    if($a.Count -gt 0) {
-        $n = $a.Count - 1
-        0..$n | foreach{ "$($a[$_][0..$n])" }
+    if($a) {
+        0..($a.count - 1) | foreach{ if($a[$_]){"$($a[$_])"}else{""} }
     }
 }
-$A = @(@(1,2),@(3,4))
-$B = @(@(5,6),@(7,8))
-$I = @(@(1,0),@(0,1))
-$C = array-mult $A $B
-$D = array-mult $A $I
-show $C
+$a = @(@(1,2),@(3,4))
+$b = @(@(5,6),@(7,8))
+$c = @(5,6)
+"`$a ="
+show $a
+""
+"`$b ="
+show $b
+""
+"`$c ="
+$c
+""
+"`$a * `$b ="
+show (multarrays $a $b)
 " "
-show $D
+"`$a * `$c ="
+show (multarrays $a $c)