Pololu Line Sensor Array

Can the Pololu line sensor array be used to measure the amount of deviation from the line which the robot is following?

The “QTR-8RC” can. (sort of…)

#include <QTRSensors.h>

#define NUM_SENSORS             3  // number of sensors used
#define NUM_SAMPLES_PER_SENSOR  4  // average 4 analog samples per sensor reading
#define EMITTER_PIN             2  // emitter is controlled by digital pin 2

//Using RA Sensors
QTRSensorsAnalog qtra((unsigned char[]) {0, 1, 2}, NUM_SENSORS, NUM_SAMPLES_PER_SENSOR, EMITTER_PIN);
unsigned int sensor_values[NUM_SENSORS];

void setup() 
{
    delay(500);
    Serial.begin(9600); // set the data rate in bits per second for serial data transmission
    delay(1000);
    int i;
    for (i = 0; i < 250; i++)  // make the calibration take about 5 seconds
    {
        qtra.calibrate();
        delay(20);
    }

}

void loop() 
{
      // put your main code here, to run repeatedly:
      //qtrrc.readLine(sensor_values);
      qtra.readLine(sensor_values);
      for (unsigned char i = 0; i < NUM_SENSORS; i++)
      {
          Serial.print(sensor_values[i]);
          Serial.print('\t'); // tab to format the raw data into columns in the Serial monitor
      }
      Serial.println();
  
      delay(250);

}

I am using a Pololu QTR - 3A reflectance sensor array.
For the above code, I am getting the following values.

0 0 0
0 0 0
3 3 3
0 0 0
0 0 0
3 3 3
0 0 0
3 3 3