title: It there a way in powershell to make a positive number to a negative number whitout using multiplication?
body: <p>I was wondering if there is a way to make a positive number into a negative number whitout using a multiplication like <code>$b = $a * -1</code><br>
  I'm looking for the most cost sensible way because I'm gonna do this a lot of times in a script.</p>
  
  <p>-edit
  At this point I'm using this, but lookes very costly computation wise:</p>
  
  <pre><code>    $temp_array = New-Object 'object[,]' $this.row,$this.col
  
      for ($i=0;$i -le $this.row -1 ; $i++) {
          for ($j=0;$j -le $this.col -1 ; $j++) {
              $digit = $this.data[$i,$j] * -1
              $temp_array[$i,$j] = 1 / ( 1 + [math]::exp( $digit ) )
              #[math]::Round( $digit ,3)
          }
      }
      $this.data = $temp_array
  </code></pre>