Around 2000 I was accidentally inventing a Bloom filter variant (to this day I don’t know how I missed the Google papers at the time) for doing a large set intersection test between two machines.
Somehow, I ended up with a calculus equation for determining the right number of bits per entry and rounds to do to winnow the lists, for any given pair of machines where machine A found n entries and machine B found m. But I couldn’t solve it. Then I discovered that even though I did poorly at calculus, I still remembered more than anyone else on the team, and then couldn’t find help from any other engineer in the building either.
Eventually I located a QA person who used to TA calculus. She informed me that my equation probably could not be solved by hand. I gave it another day or so and then gave up. If I couldn’t do it by hand I wasn’t going to be able to write a heuristic for it anyway.
For years, this would be the longest period in my programming career where I didn’t touch a computer. I just sat with pen and paper pounding away at it and getting nowhere. And that’s also the last time I knowingly touched calculus at work.
(although you might argue some of my data vis discussions amount to determining whether we show the either the sum or rate of change of a trend line to explain it better. The S curve that shows up so often in project progress charts is just the integral of a normal distribution, after all)
Somehow, I ended up with a calculus equation for determining the right number of bits per entry and rounds to do to winnow the lists, for any given pair of machines where machine A found n entries and machine B found m. But I couldn’t solve it. Then I discovered that even though I did poorly at calculus, I still remembered more than anyone else on the team, and then couldn’t find help from any other engineer in the building either.
Eventually I located a QA person who used to TA calculus. She informed me that my equation probably could not be solved by hand. I gave it another day or so and then gave up. If I couldn’t do it by hand I wasn’t going to be able to write a heuristic for it anyway.
For years, this would be the longest period in my programming career where I didn’t touch a computer. I just sat with pen and paper pounding away at it and getting nowhere. And that’s also the last time I knowingly touched calculus at work.
(although you might argue some of my data vis discussions amount to determining whether we show the either the sum or rate of change of a trend line to explain it better. The S curve that shows up so often in project progress charts is just the integral of a normal distribution, after all)