will contain the largest number from the array when you run the programyou get the largest height achieved was which compares favorably to the plot that pops up to implement the traversing of arrays with loops and indicesis sometimes challenging to get right you need to understand the startstop and step length choices for an indexand also how the index should enter expressions inside the loop at the same timehoweverit is something that programmers do oftenso it is important to develop the right skills on these matters having one loop inside anotherreferred to as double loopis sometimes usefule when doing linear algebra say we want to find the maximum among the numbers stored in matrix the code fragment could look like largest_number [ ][ for in range( )for in range( )if [ ][jlargest_numberlargest_number [ ][jhereall the indices ( will be covered for each value of index firsti stays fixed at while runs over all its indices theni stays fixed at while runs over all its indices againand so on sketch on piece of paper and follow the first few loop iterations by handthen you will realize how the double loop construction works using two loops is just special case of using multiple or nested loopsand utilizing more than two loops is just straightforward extension of what was shown here notehoweverthat the loop index name in multiple loops must be unique to each of the nested loops note also that each nested loop may have as many code lines as desiredboth before and after the next inner loop the vectorized computation of heights that we did in ball_plot py (sect could alternatively have been done by traversing the time array (tandfor each elementcomputing the height according to the formula gt howeverit is important to know that vectorization goes much quicker so when speed is importantvectorization is valuable use loops to compute sums one important use of loopsis to calculate sums as simple exampleassume some variable given by the mathematical expression xd ii summing up the first even numbers for some given say would typically be computed in computer program as