HuasoFoundries / math_histogram

            throw new \PEAR_Exception('cannot studentize data, standard deviation is zero.');

        }

        $arr = array();

        if ($this->_dataOption == self::STATS_DATA_CUMMULATIVE) {

            foreach ($this->_data as $val => $freq) {

                $newval         = ($val - $mean) / $std;

                $arr["$newval"] = $freq;

            }

        } else {

            foreach ($this->_data as $val) {

                $newval = ($val - $mean) / $std;

                $arr[]  = $newval;

            }

        }

        return $this->setData($arr, $this->_dataOption);

    }

            return $mean;

        }

        $arr = array();

        if ($this->_dataOption == self::STATS_DATA_CUMMULATIVE) {

            foreach ($this->_data as $val => $freq) {

                $newval         = $val - $mean;

                $arr["$newval"] = $freq;

            }

        } else {

            foreach ($this->_data as $val) {

                $newval = $val - $mean;

                $arr[]  = $newval;

            }

        }

        return $this->setData($arr, $this->_dataOption);

    }