Relaxed reduce signature

Author: andrewdalpino

src/Matrix.php

@@ -567,11 +567,17 @@ public function map(callable $fn) : self
      * Reduce the matrix down to a scalar.
      *
      * @param  callable  $fn
-     * @param  float  $initial
-     * @return float
+     * @param  mixed  $initial
+     * @throws \InvalidArgumentException
+     * @return int|float
      */
-    public function reduce(callable $fn, float $initial = 0.) : float
+    public function reduce(callable $fn, $initial = 0)
     {
+        if (!is_int($initial) and !is_float($initial)) {
+            throw new InvalidArgumentException('Initial value must'
+                . ' be an integer or float.');
+        }
+
         $carry = $initial;
 
         foreach ($this->a as $row) {
@@ -610,12 +616,14 @@ public function transpose() : self
      */
     public function inverse() : self
     {
-        $b = $this->augmentRight(self::identity($this->m))->rref();
+        $b = $this->augmentRight(self::identity($this->m));
+
+        $b = $b->rref()->asArray();
 
         $c = [];
 
-        for ($i = 0; $i < $this->n; $i++) {
-            $c[] = array_slice($b[$i], $this->n);
+        foreach ($b as $row) {
+            $c[] = array_slice($row, $this->n);
         }
 
         return self::quick($c);
@@ -931,7 +939,7 @@ public function add($b) : self
             return $this->addScalar($b);
         }
 
-        throw new InvalidArgumentException('Cannot sdd matrix to a'
+        throw new InvalidArgumentException('Cannot add matrix to a'
             . ' ' . gettype($b) . '.');
     }
 

src/Tensor.php

@@ -38,10 +38,10 @@ public function map(callable $fn);
      * Reduce the tensor down to a scalar.
      *
      * @param  callable  $fn
-     * @param  float  $initial
-     * @return float
+     * @param  mixed  $initial
+     * @return int|float
      */
-    public function reduce(callable $fn, float $initial = 0.) : float;
+    public function reduce(callable $fn, $initial = 0);
 
     /**
      * A universal function to multiply this tensor with another tensor

src/Vector.php

@@ -381,11 +381,17 @@ public function map(callable $fn) : self
      * Reduce the vector down to a scalar.
      *
      * @param  callable  $fn
-     * @param  float  $initial
-     * @return float
+     * @param  mixed  $initial
+     * @throws \InvalidArgumentException
+     * @return int|float
      */
-    public function reduce(callable $fn, float $initial = 0.) : float
+    public function reduce(callable $fn, $initial = 0)
     {
+        if (!is_int($initial) and !is_float($initial)) {
+            throw new InvalidArgumentException('Initial value must'
+                . ' be an integer or float.');
+        }
+
         return array_reduce($this->a, $fn, $initial);
     }