From my college experience I never needed a Ti or Hp calculator. Most of the questions did not require anything more complex than logarithms, exponential, root and trigonometric functions. A good question should be about concepts, not results. I remember a linear algebra test in where you had to solve a problem by inverting a matrix to get a result, the problem was that the matrix was so large that it could have taken the entire test time to get the result if done by hand. However if you were clever, and knew the matrix properties being tested, the matrix could be simplified and the result gotten in 3 steps. If you had a Ti or HP you could have entered the matrix and get the result, but the question would have lost its meaning
For many business-type courses they like you to be able to quickly get an IRR or NPV value. One could solve that by hand, but the exams would be long and require manual grading. According to my older colleagues when I started my career, they used to bring their HP calculators to client meetings before laptops were a thing. They would sit around and do estimated calculations. If you look at old photos, your can see the HP calculators in them and paper with written calculations. When I started my career in 2000, laptops were already ubiquitous. There were still old timers with the RPN calculators from HP. Excel is better for finance. For real analysis and simulation stuff like Mathmatica and Maple are better, with SAS, SPSS and R for statistics, although SAS is used a ton in finance, insurance as well as government.
That's another point, during college some tests were and multiple choice questions. They were manually graded and for each answer you needed to prove how did you get the answer. I don't remember any kind of automated grading system. Everything was done by hand, whether by the teacher or TA's
I’ve known people who has dropped out of college after receiving job offers during their internships. The problem is that some companies cap your your maximum pay and promotions unless you finish college even though you had excellent performance reviews. So you either stay on college and lose the job opportunity, or stay knowingly that at some point you’ll have to come back to college to finish your degree.
IIRC correctly the original Java VM was a stack based machine. That made sense when it was first created since a stack based machine is the simplest system you can create that run code and since it only need three registers, one for the instruction, one for the first data and one for the top of the stack for the other data. The problem is that you need to push and pop a lot from the stack during runtime which means more memory accesses and more time spent on gathering the data than on doing actual operations. That also underutilizes the processor registers since on a normal processor you would be using two data registers at most. This was one of the early issues with java running slowly on android and the reason of the creation of the Dalvik VM which was a register one.
You compile the stack based code into register code. It is, of course, easier to say than to do, but it is within the range of a skilled team, not absurdly complicated.
You can think about it on a really small scale:
PUSH 1
PUSH 2
PUSH 3
ADD
PUSH 4
MULT
ADD
is not that hard to conceptually rewrite into
STORE 1, r1
STORE 2, r2
STORE 3, r3
ADD r2, r3 INTO r2
STORE 4, r3
MULT r2, r3 INTO r2
ADD r1, r2 INTO r1
Of course, from there, you have to deal with running out of registers, then you're going to want to optimize the resulting code (for instance, generally small numbers like this can fit into the opcodes themselves so we can optimize away all the STORE instructions easily in most if not all assembly languages), but, again, this is all fairly attainable code to developers with the correct skills, not pie-in-the-sky stuff. Compiler courses do not normally deal directly with this exact problem, but by the time you finish one you'd know enough to tackle this problem since the problem since the problem that compiler courses do deal with is a more-or-less a superset of this problem.
oh okay, so you're not really running the original byte code. You're cross-compiling it to a different architecture effectively. That makes sense then!
From memory unreal tournament and other fps that used the same engine had support for opengl, glide, d3d , s3tc and software rendering. It was one of the most compatible render engine
Not sure if you read Generation Kill or watched the miniseries, but that is one of the main points. In there, there were two platoon commanders, Lieutenant Fick and Captain America(The book never reveals its name, and I think the series does, but I don't recall at this moment). While Lieutenant Fick was a competent officer that tried to kept the welfare of his troops, he often butted heads with its direct superiors since the order given to him could endanger the lives of his subordinates while not accomplishing nothing of value. In contrast Captain America, was an incompetent officer who gave reckless orders, was ignored by his troops and could have been possibly be charged with war crimes. At the end of the series, when the journalist is interviewing the battalion commander about why Captain America was never disciplined for his actions, the battalion commander answers that the same leeway that he gave to Lieutenant Fick was given to Captain America. In other words if he were to punish Captain America, he should also be punishing Lieutenant Fick. In retrospective is understandable, but when you read or watch it, you wonder why no action is being taken to discipline Captain America and why no one listens to Lieutenant Fick
The USA has 240 volt plugs. They are only used for high power appliances such as AC or ovens. If you want, you could add a plug for your high powered space heater AKA gaming PC.
I’m aware we have 240V outlets. They are just not used in a place where you would put a PC. Until there is a shift in need (I.e., every normal user would need more than a 120V plug could handle), you won’t ever see 240V outlets in offices. I suspect it will never happen.
In server areas and extremely specialized stuff? Yea, sure. But we’re talking desktop PCs here.
Most of the US utilizes the NEC for installation compliance. Per NEC, 15A-style outlets are "to code" on 20A circuits unless a single recepticle ("dedicated") circuit — in which case a 20A-style recepticle MUST be installed.
For any electric appliance (including computers) which operates for 3hrs+ ("continuously"), the circuit rating is reduced to 80% capacity (e.g. only 16A load allowed continuously on a "20A circuit" == only 1920W computers allowed on 20A circuit, 1440W on 12A).
Pro tip: check your own PSU, but practically all modern computers can handle AC input 100-240V (all you need is the correct IEC power cord for a 240 US plug).
I have fixed enough melted devices in my career to always twice-torque each&every connection I make. For temporary extension cords/plugs, "twist lock" ends are worth all the extra dollars.
Protips: use Eeez-Ox (a conductive paste which inhibits corrosion) for high-load applications (non-data, only). My own gamerig's AMD GPU has it (sparingly applied) within its dual 8-pin connectors. I supply the 8-pin connectors from a single pair of 8awg copper, which is directly soldered within the PSU's PCB power-take-offs... so only a few inches of 16awg for voltage drop (into the GPU), which reduces the amperage required (but is also unnecessary overkill).
It’s the whole chain - 20a outlets typically require 12ga wire instead of 14ga, a 20 amp breaker, and yes - the outlet is different. The 20a outlets add a horizontal opening to one of the 2 vertical slots, making a sideways T shape. Devices that require 20 amps will have one of those horizontal prongs to ensure you don’t plug them in to a 15 amp outlet.
The outlet itself doesn't care, but the shape of the receptacle is supposed to restrict insertion of a 20 amp device into a 15 amp socket. You can stick a 15 amp device into a 20 amp socket, but not vice versa. The electrician should be installing 20 amp sockets if the cabling can support it, but many don't.
20a outlets are also expensive compared to 15A ones. When redoing the electrical in the house I inherited I put a dedicated circuit in the living room for the TV/game consoles/etc since my daughter's gaming rig would be going in the living room as well; since I hadn't decided to put the recessed panel for the TV wiring in at the time it was the only outlet on the circuit and code dictates that a 20A circuit with a single outlet must use a 20A receptacle.
I can buy a 10-pack of nice 15A Leviton Decora Edge outlets (that use lever lock connectors instead of screw terminals) for $26 ($2.60 each), but basic 20A tamper resistant outlets (which newer editions of the NEC require anywhere a small child can access them) are $6+ a pop.
When nothing outside of my electrical room (where the servers live) has need of a 20A receptacle it's kind of pointless to spend the extra money on them, but the extra couple bucks on 12 gauge copper is always wise.
It has long been my understanding that a single regular, bog-standard 15A duplex (ie, dual outlet) receptacle meets the multi-receptacle requirement of a 20-amp branch circuit.
If my understanding is correct, then you overkilled it and you could have saved a few dollars, at least one welli-intentioned rant, and still have been compliant with NEC.
A literally-single 15A outlet like a Leviton 16251-W would not pass muster, while one dual-outlet example of the 15-amp lever-lock devices you mention would.
Well, the rant still applies either way - the 20A outlets are 2x the cost, that's the big reason why the aren't routinely installed. I was thinking when I embarked on the project "oh, I'll just put 20A ones everywhere because why not?" and immediately decided not to when I looked at the prices for the packs of outlets....
I had the luxury (or curse, depending) once of owning a home that needed all of the wiring replaced.
Being the kind of person that I am, I overbuilt things as I felt was appropriate. As part of that, I certainly wanted to install 20 amp outlets (even though I've never held in my hand a 20 amp plug).
The cost of that, vs good spec-grade 15A duplex outlets, was insane.
I know that the only difference is using one T-shaped contact instead of a straight and some different molds for the plastics. The line producing T-shaped contacts already exists, and so do the molds. Every 15A outlet sold today can transfer 20A safely.
It should be pennies difference in cost, and it was instead whole dollars.
Sucks.
(I'm reasonably certain that we are going to be broadly stuck with this low-current, low-voltage business until something very different comes along, and that any of this is unlikely to change in my lifetime.)
If the cheaper 14guage wire was used in the walls then only the 15 amp socket is appropriate, otherwise you might plug in a 20amp device and melt the wires or burn down the house.
Not really. 15A receptacles are required by code to be able to handle 20A of current at their terminals, so the larger wire and breaker allows for more loads to be run instead of one big load to draw it all (and if you need that, then a 20A circuit with a single receptacle does actually require it to be a 20A receptacle).
The shape of the outlet is different for different current allowances (the spades are wider or rotated). It is supposed to allow an electrician to indicate that the whole circuit is rated to handle the higher expected load, and that there aren’t other outlets on the same circuit which might also try to use the whole current available. Basically a UI problem trying to encourage robust designs for use by non-experts
British kettles draw so much power, the electric utility had to consider the additional power draw on the grid from synchronized tea-making during the commercial breaks of a popular soap opera, back when broadcast TV was king.
> I envy my European friends' 240v electric kettles
... do you not have electric kettles in the US? Foolishly, I thought this was a standard kitchen appliance all over the world, I've even seen it in smaller cities in Peru.
We do. Like others have said, they're unusual here -- in part, because culturally we drink a lot more coffee than we do tea, but also because heating a large-ish volume of water with a normal American outlet takes awhile.
My solution to drinking a cup of tea is also unusual: I have a no-longer-in-production Sunbeam Hotshot and I use it heat only as much water as I need right now.
It raises one tea-cup worth of water from whatever temperature it is that comes out of the cold tap to boiling in about 40 seconds.
I just dump a cup of water in, push one button to heat it up, wait until it boils, and then push another button to dispense that hot liquid into the cup that I'm using for tea.
We do, but they’re limited to much lower wattage due to the outlet limits. A typical US kettle is 1100-1400W, and takes maybe 1-2 minutes to boil. Kettles in the UK are typically 2.5-3kW.
And they're probably not real. Take look at any of the clones of the dyson hair dryer and check their proclaimed RPMs, many of them would have the tip of the fan blade spinning at several mach if they actually hit their limit.
There's aquarium heaters on amazon that say they're 10kw or more and plug into a 120 outlet.
I bought a magnet that is supposed to hold "150 pounds", but pulls off the ceiling (in it's strongest position) with just 10-15 pounds.
What's your point? There's likely a few 1800W kettles that exist too. They are not common, and you definitely will never see anything above 1800W (outside of maybe some specialized commercial product designed for an 20A outlet) in the US. A 'normal' average kettle is going to be ~1200W here. Kettles start at 2kW and go up from there in the UK.
We don't have a need for an exclusive water boiling device as we aren't obsessed with tea. Most people drink coffee and the heating element is already built into the coffee maker. Idk what else you'd use it for. The stove works fine for boiling water without needing a separate appliance.
They’re far faster than a stovetop most of the time, have auto shutoff so you can wander away for a minute or two or not pay attention to it and not boil off a lot of water, etc.
Many parts of the world, it’s a good idea to boil water before using it for drinking, brushing teeth, etc.
So it’s actually really convenient for many use cases besides tea or coffee.
That's fine, but there are no use cases in the US. If we are boiling water, it's for food, and we're doing it on the stove, just like the way everyone else cooks. In the US, there is no use case for a specialized water boiling appliance.
We can agree they're less common than the UK, but saying they have "no use case" is a gross exaggeration. Pretty much everyone I know owns a kettle, given how cheap they are (~$15-20 for an OK one). Great for hot chocolate, coffee, tea, boiling water for a pot of water (to speed it up vs heating up your entire house), and numerous other reasons.
I have been known to heat water in a microwave after doing the calculations needed to know roughly when the water would reach boiling. It is rather quick once the microwave timer starts going.
They’re readily available, but most households don't actually have one. Many more households have a coffee maker, which is essentially the same thing but specialized for dripping the boiling water through coffee grounds. Anyone else who needs boiling water just puts a pot on the stove, or possibly an old–fashioned metal tea kettle.
We could even use 240v electric tea kettles here in the US if we wanted to; most kitchens with an electric range and oven have 240v (or 208v) outlets to plug them in to. But those outlets are usually inconveniently located for counter–top appliances. It wouldn’t cost much to add another above the counter, but it is rarely done in practice. Of course, in many parts of the US natural gas heating is cheaper than electric so the houses there are built for gas ranges and ovens instead.
The problem there would be your breaker. I am not an electrition but I can tell you that when I tried adding a heated MAU to my house, I had to switch to a 120v washer/dryer because my electric panel did not have space for another 208v line.
(Note, my building is actually 3 phase 208 volt not 240volt so I don't have 240 volt plugs but 208volt plugs)
Not a criticism, but a question. Did you consider adding a subpanel? If you're running a new circuit I assume there was already some drywall patching to be done, seems like it would have been more cost effective and removed future headaches to just give yourself more breaker space.
A lot is going to depend on labor rates for your local electricians, but that costing more than $500 where I am would be outrageous. I do my own electrical, but even I paid a licensed electrician to come handle installing a new panel since I did not have an outdoor service disconnect and didn't feel like fighting with the utility company over de-energizing and re-energizing my service. Ended up needing a lot more done, but the whole thing cost me $2500 to get a new service drop, outdoor meter main, and wiring run to the old panel (in the bedroom on the other side of the main) and the new panel (in the old furnace closed that's now my electrical / network room).
But really, doing a subpanel yourself to expand breaker capacity is a really simple project - most people if so inclined could do it themselves. Anywhere from $100-200 for the panel itself depending on how many spaces you feel like adding, up to $80 for a large enough breaker to feed it, and some tens of dollars for SER cable.
Agreed - I’ve ended up installing 4 (inspected) ones over the years myself, and one I paid an electrician for (they also had to upgrade the main service feed).
IMO, what usually drives up the price is the ancillary stuff - opening up a wall (and re-finishing it) because there isn’t enough physical space, or adding extra main panel capacity/service capacity because the main feed is insufficient, or having to run heavier than expected wiring because the only available space gets really hot (poorly ventilated attic space), or having to run surface conduit due to a specific challenge with framing.
Then add in labor (where I was in a high cost of labor area), and it can get expensive quick.
An actual surface mount subpanel and appropriate wires/breakers is usually only a couple hundred bucks total like you note.
NEC code requires 2 separate 20 amp circuits in a kitchen. Usually they split the circuits across a countertop or window. It's been code since ... as far as I can tell, pretty much forever. Unless you're living in a house that is either non-compliant or built before NEC was required, then it should have this kitchen arrangement.
I remember reading that rodents chewed car cables since the insulation was made using the same compound as soy and that attracted them, but in reality it was just they liked chewing on stuff.
https://www.caranddriver.com/news/a21933466/does-your-car-ha...
I just read that article and it doesn't appear to agree with your conclusion. That was just a single quote from a a pest control guy who works for Orkin.
The article does say that car owners and mechanics have noted a large increase in rodent damage to car wiring with the new soy-based insulation while manufacturers have denied any connection. Likely because they are fighting several class-action lawsuits over it.
I think the better word is tradeoff since there are no perfect data structures for each job. The hasmap has the advantage of O(1) access time but the drawback of memory usage, an unsorted nature and the depends on a good hashing function to minimize collisions. A vector is also O(1), but it has an upfront memory cost that cannot be avoided. A map has a O(Log(n)) access cost, but has less memory usage, is sorted by nature and the comparison function is easier to implement.
Three similar data structures, but each with its own tradeoffs.
Well it had happened in the past when they phased out lead from gasoline. Older would run poorly because they were tuned for that particular gasoline type
Ground loops comes from the ground mismatch between two electrically connected devices. When you use an optical link, you isolate those two devices since there is no common ground and the hum goes away. Same if connect a battery device to a grounded device.
