Yeah, Oracle’s free tier is much more generous than any other cloud provider. They’ve offered that amount of ram for at least a couple years now but we’ll see.
On a trip about 18 months ago I had some Kia soft-roader hire car. I bloody hated the lane keeping (unfamiliar narrow twisty roads are bad enough without the car tugging on the steering wheel).
Conversely the auto-distance thing with cruise control is fantastic - it makes CC usable at way higher traffic densities.
Yes, lane keeping can be quite annoying. I regularly drive a road with side markings but no center marking. The car interprets this as a single lane and constantly tugs my steering wheel into oncoming traffic.
It's a somewhat different kind of ring buffer, because there's just one index, but I used it in my signal processing class for a finite-impulse-response filter.
Choose N to be a power of two >= the length of your filter.
Increment index i mod N, write the sample at buffer position x[i], output sum of x[i-k mod N] * a[k] where a[k] are your filter coefficients, repeat with next sample at next time step.
In Brisbane I think our ticketing system cost overhead is maybe 10%?
The cost of the programme rolling out new ticketing infra (the first major ticketing system upgrade in ~15 years since we first got integrated ticketing, going from a stored-value smart card to also being able to tap your credit card) is roughly the same amount of money as the annual revenue from fares.
So hundreds of millions of dollars to be saved then, and that's just for the periodic upgrades, which are an up-front cost and therefore cost you even more in terms of time value of money.
Then as long as the system is in place you need to pay ongoing costs to repair and maintain the equipment, enforcement against anyone who skips the fare, payment network fees, customer service for anyone with payment issues or damaged cards, connectivity service for anything that needs to be networked, etc.
And the overhead percentage depends on the fares. If it was ~10% when the fare was $5, what is it when the fare is $0.50? Well:
> If fare revenue is now only about $20 million per year, does it even cover the cost of fare collection? The current ticketing system rollout was expected to cost $371m, but ended up at $434m – which appears to cover operations for 17 years from 2018… so $25.5m per year. [0]
You'll find that when the number of columns is a multiple of 6 you'll get obvious columns in the dots, and if it's +1 or -1 modulo 6 the columns become diagonal stripes (the process sort of continues for ±2 and at ±3 it's pretty broken down).
It's a fairly straightforward number theory result that every prime > 3 is congruent to ±1 modulo 6 so that's probably what you're seeing.
(Can't be +2 or +4 because that's divisible by 2, can't be +3 because that's divisible by 3, leaving +1 and +5 aka -1.)
