How to change width and height of occupancy grid

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Hi, I'm using ROS Indigo. I used gmapping with turtlebot to get the map and i changed the resolution of the map from 0.005 to 1 in gmapping.launch.xml file. Now I observed that the new map contains 10x10 grid cells.But when I subscribe the /map topic I got a tuple of length 4096. Then i converted it into a matrix of 64x64. How to change the width and length to obtain a 10x10 matrix when i subscribe the topic /map.??