Interquartile Range ( IQR ) | Function to give index of the median ; Function to calculate IQR ; Index of median of entire data ; Median of first half ; Median of second half ; IQR calculation ; Driver Code
function median ( a , l , r ) { var n = r - l + 1 ; n = parseInt ( ( n + 1 ) / 2 ) - 1 ; return parseInt ( n + l ) ; } function IQR ( a , n ) { a . sort ( ( a , b ) => a - b ) ; var mid_index = median ( a , 0 , n ) ; var Q1 = a [ median ( a , 0 , mid_index ) ] ; var Q3 = a [ mid_index + median ( a , mid_index + 1 , n ) ] ; return ( Q3 - Q1 ) ; } var a = [ 1 , 19 , 7 , 6 , 5 , 9 , 12 , 27 , 18 , 2 , 15 ] ; var n = a . length ; document . write ( IQR ( a , n ) ) ;