September Morn Update

Task/Matrix-multiplication/AWK/matrix-multiplication.awk

@@ -0,0 +1,54 @@
+# Usage: GAWK -f MATRIX_MULTIPLICATION.AWK filename
+# Separate matrices a and b by a blank line
+BEGIN {
+    ranka1 = 0; ranka2 = 0
+    rankb1 = 0; rankb2 = 0
+    matrix = 1 # Indicate first (1) or second (2) matrix
+    i = 0
+}
+NF == 0 {
+    if (++matrix > 2) {
+        printf("Warning: Ignoring data below line %d.\n", NR)
+    }
+    i = 0
+    next
+}
+{
+    # Store first matrix in a, second matrix in b
+    if (matrix == 1) {
+        ranka1 = ++i
+        ranka2 = max(ranka2, NF)
+        for (j = 1; j <= NF; j++)
+            a[i,j] = $j
+    }
+    if (matrix == 2) {
+        rankb1 = ++i
+        rankb2 = max(rankb2, NF)
+        for (j = 1; j <= NF; j++)
+            b[i,j] = $j
+    }
+}
+END {
+    # Check ranks of a and b
+    if ((ranka1 < 1) || (ranka2 < 1) || (rankb1 < 1) || (rankb2 < 1) ||
+        (ranka2 != rankb1)) {
+        printf("Error: Incompatible ranks (%dx%d)*(%dx%d).\n", ranka1, ranka2, rankb1, rankb2)
+        exit
+    }
+    # Multiplication c = a * b
+    for (i = 1; i <= ranka1; i++) {
+        for (j = 1; j <= rankb2; j++) {
+            c[i,j] = 0
+            for (k = 1; k <= ranka2; k++)
+                c[i,j] += a[i,k] * b[k,j]
+        }
+    }
+    # Print matrix c
+    for (i = 1; i <= ranka1; i++) {
+        for (j = 1; j <= rankb2; j++)
+            printf("%g%s", c[i,j], j < rankb2 ? " " : "\n")
+    }
+}
+function max(m, n) {
+    return m > n ? m : n
+}

Task/Matrix-multiplication/BASIC/matrix-multiplication-2.basic

@@ -0,0 +1,14 @@
+DIM matrix1(4,2),matrix2(2,3)
+
+MAT READ matrix1
+DATA 1,2
+DATA 3,4
+DATA 5,6
+DATA 7,8
+
+MAT READ matrix2
+DATA 1,2,3
+DATA 4,5,6
+
+MAT product=matrix1*matrix2
+MAT PRINT product

Task/Matrix-multiplication/Ceylon/matrix-multiplication.ceylon

@@ -0,0 +1,65 @@
+alias Matrix => Integer[][];
+
+void printMatrix(Matrix m) {
+	value strings = m.collect((row) => row.collect(Integer.string));
+	value maxLength = max(expand(strings).map(String.size)) else 0;
+	value padded = strings.collect((row) => row.collect((s) => s.padLeading(maxLength)));
+	for (row in padded) {
+		print("[``", ".join(row)``]");
+	}
+}
+
+Matrix? multiplyMatrices(Matrix a, Matrix b) {
+	
+	function rectangular(Matrix m) =>
+			if (exists firstRow = m.first)
+			then m.every((row) => row.size == firstRow.size)
+			else false;
+	
+	function rowCount(Matrix m) => m.size;
+	function columnCount(Matrix m) => m[0]?.size else 0;
+	
+	if (!rectangular(a) || !rectangular(b) || columnCount(a) != rowCount(b)) {
+		return null;
+	}
+	
+	function getNumber(Matrix m, Integer x, Integer y) {
+		assert (exists number = m[y]?.get(x));
+		return number;
+	}
+	
+	function getRow(Matrix m, Integer rowIndex) {
+		assert (exists row = m[rowIndex]);
+		return row;
+	}
+	
+	function getColumn(Matrix m, Integer columnIndex) => {
+		for (y in 0:rowCount(m))
+		getNumber(m, columnIndex, y)
+	};
+	
+	return [
+		for (y in 0:rowCount(a)) [
+			for (x in 0:columnCount(b))
+			sum { 0, for ([a1, b1] in zipPairs(getRow(a, y), getColumn(b, x))) a1 * b1 }
+		]
+	];
+}
+
+shared void run() {
+    value m = [[1, 2, 3], [4, 5, 6]];
+    printMatrix(m);
+    print("---------");
+    print("multiplied by");
+    value m2 = [[7, 8], [9, 10], [11, 12]];
+    printMatrix(m2);
+    print("---------");
+    print("equals:");
+    value result = multiplyMatrices(m, m2);
+    if (exists result) {
+        printMatrix(result);
+    }
+    else {
+        print("something went wrong!");
+    }
+}

Task/Matrix-multiplication/Perl/matrix-multiplication.pl

@@ -16,3 +16,20 @@ sub mmult
      }
   return [@p];
  }
+
+sub display { join("\n" => map join(" " => map(sprintf("%4d", $_), @$_)), @{+shift})."\n" }
+
+@a =
+(
+   [1, 2],
+   [3, 4]
+);
+
+@b =
+(
+   [-3, -8, 3],
+   [-2,  1, 4]
+);
+
+$c = mmult(\@a,\@b);
+display($c)

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

@@ -1,24 +1,19 @@
 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
-            }
+    $n,$m,$p = ($a.Count - 1), ($b.Count - 1), ($b[0].Count - 1)
+    if ($a[0].Count -ne $b.Count) {throw "Multiplication impossible"}
+    $c = @(0)*($a[0].Count)
+    foreach ($i in 0..$n) {
+        $c[$i] = foreach ($j in 0..$p) {
+            $sum = 0
+            foreach ($k in 0..$m){$sum += $a[$i][$k]*$b[$k][$j]}
+            $sum
         }
     }
     $c
-}
-function show($a) {
-    if($a) {
-        0..($a.count - 1) | foreach{ if($a[$_]){"$($a[$_])"}else{""} }
-    }
-}
+ }
+
+function show($a) { $a | foreach{"$_"}}
+
 $a = @(@(1,2),@(3,4))
 $b = @(@(5,6),@(7,8))
 $c = @(5,6)

Task/Matrix-multiplication/Standard-ML/matrix-multiplication-1.ml

@@ -0,0 +1,19 @@
+structure Matrix = struct
+local
+    open Array2
+    fun dot(x,y) = Vector.foldli (fn (i,xi,agg) => agg+xi*Vector.sub(y,i)) 0 x
+in
+val fromList = fromList
+fun x*y = tabulate ColMajor (nRows x, nCols y, fn (i,j) => dot(row(x,i),column(y,j)))
+(* for display *)
+fun toList a =
+    List.tabulate(nRows a, fn i => List.tabulate(nCols a, fn j => sub(a,i,j)))
+end
+end;
+(* example *)
+let open Matrix
+    val m1 = fromList [[1,2],[3,4]]
+    val m2 = fromList [[~3,~8,3],[~2,1,4]]
+in
+    toList (m1*m2)
+end;

Task/Matrix-multiplication/Standard-ML/matrix-multiplication-2.ml

@@ -0,0 +1 @@
+val it = [[~7,~6,11],[~17,~20,25]] : int list list

Task/Matrix-multiplication/VBA/matrix-multiplication.vba

@@ -0,0 +1,3 @@
+Function matrix_multiplication(a As Variant, b As Variant) As Variant
+    matrix_multiplication = WorksheetFunction.MMult(a, b)
+End Function