def filter_arr(arr, columns, cutoff):
    """
    Uses max: return a new array of all rows from input arr with at least one
    value in columns exceeding cutoff.
    """
    newarr = arr[[row for row in range(len(arr)) if max([val for col,val in
                enumerate(arr[row]) if col in columns]) > cutoff]]
    del arr
    return newarr