public function previousXY()
    {
        if (($this->keyY()-1)>0) {
            $this->seekY($this->keyY()-1);
        } else {
            if (($this->keyX()-1)>0) {
                $this->rewindY();
                $this->seekX($this->keyX()-1);
            } else {
                $this->x = null;
                $this->y = null;
            }
        }
        return $this;
    }
public function previousXY()
    {
        if (($this->keyY()-1)>0) {
            $this->seekY($this->keyY()-1);
        } else {
            if (($this->keyX()-1)>0) {
                $this->rewindY();
                $this->seekX($this->keyX()-1);
            } else {
                $this->x = null;
                $this->y = null;
            }
        }
        return $this;
    }
public function previousXY ( ) { if ( ( $ this -> keyY ( ) - 1 ) > 0 ) { $ this -> seekY ( $ this -> keyY ( ) - 1 ) ; } else { if ( ( $ this -> keyX ( ) - 1 ) > 0 ) { $ this -> rewindY ( ) ; $ this -> seekX ( $ this -> keyX ( ) - 1 ) ; } else { $ this -> x = null ; $ this -> y = null ; } } return $ this ; }
Seek to previous cell

@return  $this
Seek to previous cell