Euleryx Problem 13 – Large Sum
My workflow:
Spoiler
Answer: 5537376230Last Week's Favourite Solution:
Well, compared to my solution, everyone else's solutions ran in an instance so it was very helpful to see all the different ways to solve problem 12 quickly. Key take away for me was to look carefully at any iteratives (use a generate rows if possible)! But as always there is a winner, it was a particularly tough decision but for a very impressive run time of <2 seconds and no macros required, @CoG has won this weeks award! Please find this solution on page one of last week's post or click here.
Mathematical Theory:
This week's challenge is admittedly very easy for Alteryx to handle, so I'm going to add an extra layer to think about. What if we wanted the first 20 digits from the sum?
Some numeric data types only allow for a certain level of precision, whilst a double can often seem like the easy option, it comes with its own challenges when dealing with large numbers. If you look at the documents, you’ll quickly realise that a double is only accurate to 15 digits.
https://help.alteryx.com/current/en/designer/file-types-support/data-types.html#id624812
So how can we handle 50 digits? I could attempt to explain this myself, but instead, I would like to point you in the direction of the article that first taught me how to get around this issue. Yes, I have referenced this blog before, but I'm going to do so again - @Gaurav_Dhama_ released a blog that not only discusses this issue but also explains how certain tools can be deceptive and even convert numeric values to different data types in the background. For anyone interested, I would strongly recommend a read. (Handling Unusually Large Numbers)
Method:
1) Convert the data type of the inputs to a fixed decimal. As there are 100, 50-digit numbers, we know the maximum number of digits possible after summing them will be 52 so just make sure the fixed decimal precision is > 52.
2) Use the summarise tool to sum the data.
3) Submit your answer to the Project Euler Website!
Summary:
Although the problem itself is no match for Alteryx, this problem can help highlight the importance of numeric data types and draw attention to the fact that you can't just set everything to be a double! For anyone seeking more of a challenge, don't worry, next weeks problem certainly requires more than 2 tools.
Want to find out more, follow this link to our introduction post - Euleryx: Let The Games Begin.
