python finding largest number

[NeatSquidYT]

Ah. Our computing teacher seems to swear by Python 2 so I have no clue about Python 3.

eww Python 2

 

You doing GCSE in it? I thought Py3 was mandatory for GCSE

[Tedster]

eww Python 2

 

You doing GCSE in it? I thought Py3 was mandatory for GCSE

We're doing Python 2 for whatever reason. For all I know we could end up switching to Python 3 but seeing how little some of us seem to grasp so far it seems unlikely.

[Azgoth 2]

Could you use the built-in max() function?  It wouldn't tell you how many times the largest value appears, but it would tell you what the largest value is.  Same thing with min(), but it'll tell you the smallest value.  You could use this to get the number of times the largest/smallest value occurs, too, by checking to see if each value in the list equals the max/min value and doing something from there.  And with some more cleverness (like a dictionary or using the list.index() method) you could print which value (first/second/etc or A/B/etc) is the max/min.

[madknight3]

I guess, sorting seems better then having lots of ifs, simple options tend to be better.

 

Sure, using ifs is fine as a learning exercise but it's not a good way to solve the problem and shouldn't ever actually be put to use. As the array size grows, the amount of code needed to calculate it with ifs grows a lot and it's very ugly.

 

A sorted array can be very useful. You can get the max and min in O(1), you can apply a binary search, etc. However if all you want is the min/max value, then sorting is overkill. The best sorting algorithms run in O(nlogn) where as a simple min/max algorithm will run in O(n) on an unsorted array. Bubble sort isn't even the best sorting algorithm so it would be even slower.

 

Now none of this really matters on an array of 5 elements, but I figured I'd explain it anyway.

[vorticalbox]

Sure, using ifs is fine as a learning exercise but it's not a good way to solve the problem and shouldn't ever actually be put to use. As the array size grows, the amount of code needed to calculate it with ifs grows a lot and it's very ugly.

 

A sorted array can be very useful. You can get the max and min in O(1), you can apply a binary search, etc. However if all you want is the min/max value, then sorting is overkill. The best sorting algorithms run in O(nlogn) where as a simple min/max algorithm will run in O(n) on an unsorted array. Bubble sort isn't even the best sorting algorithm so it would be even slower.

 

Now none of this really matters on an array of 5 elements, but I figured I'd explain it anyway.

 

i know c# has array.sort() which I believe to be pretty fast. last year in college i did a whole unit on "data structures" which basically boiled down to creating a bubble search and doing one manually.

[madknight3]

i know c# has array.sort() which I believe to be pretty fast. last year in college i did a whole unit on "data structures" which basically boiled down to creating a bubble search and doing one manually.

 

Bubble sort is a common algorithm to start teaching sorting algorithms with, however it isn't the fastest. The further you go into data structures and algorithms, the more you'll learn about the different algorithms. It's a very interesting topic, and is very useful for programmers to learn about.

 

Pretty much every language has common algorithms, like sort, available in its library and they tend to be well optimized. They don't all use the same algorithms, although they all tend to be based around the fastest options.

• C#'s Array.Sort internally uses a Quicksort.
• Java's Array.Sort uses a Quicksort and Timsort.
• Python's sort method uses Timsort.
• etc