Legs are very weak

Question: So, I've been riding at different levels of difficulty for years now, from a 33lb, one gear bmx to a 21 speed, 44lb mountain bike, and now to a 22lb, 21 speed road bike. Each bike had its own challenges, and I've always tried to ride my hardest. (lungs burning, legs weak, etc) for my entire ride, but even now, years later, I can barely surmount some hills and when I do, my cadence drops to a very low pace of around 30rpm. Is there any way to improve my leg strength? Have I been doing something wrong?
Edit: I live in Sierra Vista, AZ, but I don't know how relatively hilly it is.
Comment: You definitely want to be in the middle or small ring on the front, and stick to the larger gears in the back when climbing.
Comment: It's unclear, when you're hitting a low cadence uphill or a high cadence downhill, what the gear range of your bike is.  If you're doing 30 cadence and you have lower gears you could be using (but aren't), there's your problem.
Comment: What gear (front and rear) are you in on you 21 speed road bike?  If you have a triple you should have some really low gears available.
Comment: Try riding at easier pace and save your strength for the hills. It's common and often recommended to take it so easy that you can talk without problems for most of the time and and do only short intervals at full effort.
Comment: If your cadence drops below 50 uphill you should shift to an easier gear because you're pedalling in an anaerobic mode. Gears have the purpose to keep the cadence up. From 70 to 90 rpm is the aim.
Comment: @Frisbee I normally stay in the last 7 gears, the largest in the front and the 3rd smallest in the back when climbing
Answer: Always "riding your hardest" is called "junk miles" because it is not possible to   always ride your hardest.  The biggest performance gains come from more targeted and disciplined riding (as suggested by mattnz).
To climb your steep hills (I assume these are relatively short, steep climbs, not a mountain pass) you need to work on developing high power over a short period of time.  The following components will likely come to play:

Strategy - Sprinters can only sprint for about 400m (if that). As such, they don't ride around the whole race at max output, they save everything they can for the last 400m.  In the same way you can't be at max output the whole hill.  Try backing off for a while before hitting the hill, even as you start climbing keep your effort low and slowly ramp up.  Aim to hit your maximal effort at the top of the hill.  As you get better you can work on starting the harder effort earlier and earlier.
Muscle recruitment - how efficiently do you fire your muscles when pedalling. For example, do your knees flail about or do you have a smooth pedal stroke.  It is hard to generate large power if you have a rough and undisciplined pedaling stroke.  The efficiency of your firing patterns is also  affected by peddling cadence (e.g., 30 RPM is too slow to stay on top of a gear).
Muscle strength -  improving how much force your muscles can generate over a short period.This is of course greatly affected by (2, 3, and 5) and is what most people think of when getting "stronger."
Mental strength - being able to push through the pain and hold on to a gear until as long as possible.  This is often underestimated, but the effect size has been estimated to be as high as 20-30%, even among pro athletes (will track down ref).
Getting your body in the proper state. Maximal output only comes when you have done all the necessary prerequisites such as sleep, rest, proper food, hydration and being properly warmed up before an effort.

All these components can be trained individually or in tandem.  Different types of interval training will work these components in various amounts.  It is hard to tell you what exercises would work best without directly observing your cycling abilities.
Comment: Yes, good work Rider_X!
Comment: @Hellreaver Fun is in being so strong you can do 100km of hills. Fun is having energy to hop around and do stunts for the kids in at the end of a ride. You'll never get fast if you don't get strong first. Riding so hard you can barely stay on the bike, gasping for air over ragged, metallic, snotty exhalations as your hip flexors and calves spasm involuntarily and the major muscles feel like they are being pulled apart by a million fire ants *for the entire ride every ride* is not fun. Train to be faster than the guys who ride like that every day without exhausting yourself in the process.
Comment: Nailed it. I can't stress the importance of strategy during a ride, and getting in *lots* of "feels fun, not hard" miles. Seems like lots of those with just the occasional deliberate tough spots within a given ride, and the occasional deliberately hard overall ride is the ticket.
Comment: @zxq9 fun is in going fast, in rising to the peak of a hill (or challenge) and surmounting it, you know?
Comment: @Hellreaver - I agree going fast is fun. But the ultimate question, is it more fun to you to go somewhat fast all the time, or face stretching, "I had no idea I could go that fast," fast some of the times?  If it's the latter you have to pick and choose your battles.  (Either that start chemical or [mechanical](https://en.wikipedia.org/wiki/Pedelec) doping to go faster all the time. No judgement!)
Answer: I get the impression when you hit the road its full out 110% effort for the length of the ride. I would suggest from the "lungs burning" description that you are over training and exercising above your anaerobic threshold.  You don;t say how often or how far you ride.
First up - your cadence is way too low and you risk damaging you knees. Go for a series of rides with the sole purpose of learning to spin at a cadence of at least 90. If possible, do this on the flat and slight down hills.
You also need to ease off and focus on long distance endurance, then introduce interval training with short (30 second) sprints, with plenty of easy days and rest periods. I suspect you would benefit from a Heart Rate monitor and working out your VO2Max and training zones (I won't go into it, it too much for one answer), and working to a training plan based on it to improve your endurance (Strength comes after endurance)
Comment: Also, work out where your aerobic threshold is and try sitting at that on the climb. It's something that's useful to be aware of when you're riding because it feeds into a whole lot of tactical decisions.
Comment: Do you have a speed and distance computer. If not, get one.
You need to re-train you body to ride at higher cadence. Forget about going faster - slow down and focus in technique. Hit those hills spinning at 120 for a week, then try to climb at 30 and see how it feels. Like any sport, get technique right and results follow, get it wrong.....

Get a HR Monitor and watch the effect of cadence on effort (HR) and speed. You might be surprised.
Comment: These are great workouts that I use that do a good amount with interval training - http://www.bicycling.com/training/fitness/how-ride-inside-indoor-trainer-workouts-cyclists.
Comment: I've noticed that I'm either pedaling at 30rpm uphill because I'm too weak to maintain a higher cadence in that gear, or I'm pedaling at 120rpm (twice a second or so) to keep the speed up to how fast I would be going if I were in a higher gear. Is there any way to rectify this? I try to find a balance between cadence and speed, but am often unable.
Answer: Time for some Pee
You need to consider PACING yourself.  Use something like strava to log your rides and see your improvements over time, because it never feels like you're getting faster at the time.
I did a hill last weekend in 8 minutes that used to take me 15 minutes, 9 months ago. Didn't feel like it at the time.
PEERS - riding alone is nice and quiet and relaxing, but there's nothing like riding with some fellow cyclists.  Ones who are slightly better than you is good - they drag you up to their levels (mentally, and physically by draughting)
PRACTICE - get out and do more climbs.  There's really no substitute.
PERFORM - This relates to pacing.  When alone on a hill - I tend to sing along quietly to myself.  The tempo of the song helps with the rhythm of the ride.  You're doing the right power output when you can't sing all the words, but can mouth them or hum the tune while breathing.  Yes - I know it sounds stupid, but it works for me.
PERSEVERE - do the same climb once or twice a month.  It gets shorter and quicker each repetition.
PEDAL - sounds simple, but just keep pedalling.  Don't coast even if there's a wee flat bit or downhill.  You can ease off the pressure, but keep spinning at 60-90 RPM
POSTURE / POSITION - the accepted wisdom is that sitting through the climb is most efficient.  If you stand then its faster and harder, but you're less efficient and will tire quicker.   This all goes out the window if there's a short section of steep grade (like going up the inside of a hairpin turn where the grade can exceed 30% for a couple metres) or any grade above 18%.  In those two cases, your bike's front wheel will be trying to lift on each downstroke so you need to position your body weight off the saddle, and accept the lower efficiency till the grade drops a bit more.
I've run out of words that start with P.  Any further suggestions?
POTION! synonym for DRINK!  okay not a Pee word until after the body has processed it, but do drink a few mouthfuls before the climb starts.  Snatch a swallow when you can on the way up too.  Dehydration is a sneak, stealing away your power and your enjoyment of the ride.
EDIT1:
PERSEVERENCE (a pee word for endurance)  Keeping your average speed up over a long run is better for the slow twitch muscles to develop.  Going hard brings in the fast twitch muscles, which have low endurance and get tired quickly and generate lactic acid quicker.
PIES (its better than "Plighter Pbike")  Every kilo you drag up the climb has to be lifted there by your legs.  Stop taking things that you don't need.  No need to go overboard with weight reduction, but do consider the benefit of a lighter item over a heavier one.
Daytime only ride?  Leave all your lights at home (I take one of each anyway, but not my usual three.)
Do you end your ride with food to spare?  Take fewer things, or make an effort to eat them so they're doing you some good.
Tools?  What can you do without?   (but I carry an 8" crescent by choice and have needed it once.)
Your clothes - do you need all the weight?   I wear cycling pants but I wear normal pants on top. mostly because I feel uncomfortable without a belt for back support.
If you're on platform pedals, shoe weight can be quite noticeable too.  I have some thin mesh shoes that cost $10 at the local cheap-shop and weigh very little.  Even thin light short socks can help save reciprocating weight
PARTY!  Mix it up.  Do a long endurance flat ride like a metric century if you can, with rest stops.   Next day do climbs with intervals of 100% effort for 20 sec then back to endurance speed for a minute.  Repeat till you get to the top.
Just occasionally, ride for fun with family or friends or some random guy on a bike who is going your way at your speed.
Then try some easy MTB or off-road tracks for a change.
PHUN!  Cycling is often seen as an end-goal in itself.  However its a means to an end, of getting fitter and getting somewhere.  If you're not enjoying the benefits, change your approach before despondency sets in.
PHUCKEDUP!  Do take a moment to check on your fellow cyclists too - My old bikes are a bit crap, and I have the odd breakdown.  Its very rare that anyone checks on me, but I always slow and ask anyone on the side of the road whether there okay.
Comment: +1 for the dehydration - it's too late if you start Panting. Other things that should be worked on are Pendurance and a Plighter Pbike.
Comment: @andy256 Done - I used PERSEVERANCE for Pendurance and  "PIES" for Plighter Pbike .  Google led me to POTIONS as a P word for drink.
Answer: 30 cadence is too low and will tend to fatigue the legs more.  Pick a lower gear.
You don't need to be a pro to climb like a pro.  And there are other videos on youtube.
As for getting better at climbing - climb more (and at a higher cadence).
Answer: Judging by the comments, you're in too high a gear.  It is easiest to pedal when the chain is around the smallest gear in the front and the largest gear in the back.  Note that the hardest/highest/fastest gear on your mountain bike is probably not nearly as fast as the highest gear on your road bike.
But... I mainly wanted to share my hill climbing strategy, because it is different:
Before reaching the hill, I get out of the saddle ( stand up ), and try to gain a little speed/cadence.
Once in the hill, my cadence will drop and it's time to sit down and lower gears.  I'm pretty good at knowing what gear I will use for the rest of the hill, so I just coast until I hit the correct speed/cadence for that gear.
Mid-hill, I stand up to stretch my legs out and then sit back down.
At a certain point, I will reach the part of the hill where I can do most of it standing up, and I will do that.  I don't make it to the top.
With about 20 or 30 seconds left in the hill, I sit back down and go at a slower pace than I was when I was climbing.  This is my cool down time, I catch my breath and drink water.
I like this strategy because it makes it so I'm not out of breath at the top of the hill.  I get to enjoy the view.  Mainly, though, it means that I stand up and quickly get to the speed that is correct for the flatter slope.
Comment: For most people, this strategy only works for short rises, say 50 meters of climbing in half a km to one km. If you need to *gain* cadence then it's already too low.

Legs are very weak


Footwear for cat-people

Question: What kind of footwear would be worn by a race of anthropomorphic cats in a fantasy setting? They live as a roughly medieval society in a temperate climate, and their feet have the same shape as cat paws.
Comment: @MorrisTheCat can't you just say what are you wearing on your feet right now?
Comment: Where do these cats live? Climate and terrain make a big difference in the answer.
Comment: @VLAZ well, if I were somewhere that wasn't going to get my paws wet I'd be wearing something different, wouldn't I?? I also don't think this is the answer OP is looking for: https://cdn.shopify.com/s/files/1/1180/3866/products/Navy_and_orange_leather_dress_shoes_900x.jpeg?v=1565002876
Answer: Cats are digitigrade, they'd be better off without shoes.
Crocs
Claws are important to cats, the holes in crocs would allow them to use their claws even while wearing shoes.
Moccasins
Cats are quiet walkers, moccasins would allow them to keep moving silently. Claw holes can be allowed for.
Clogs or other hard shoes (wood, leather or otherwise)
These are civilised cats, they make a point of being nosy as they walk to distinguish themselves from their wilder cousins who need to stalk their prey silently. Moving noisily is a symbol of status. Claws are not allowed for as again they're a sign of wilder times.
Comment: This makes me think that "gentry" might deliberately wear bells or other noise-making artifacts, besides or in addition to noisy footwear...
Comment: How does the digitigrade/planitgrade distinction affect suitability for shoes?
Comment: @NuclearWang, bipedal walking on toes is likely to be more sensitive to any imbalance, sensitivity of the feet is significantly reduced by shoes put the two together and balance and agility suffers significantly.
Comment: For those who don't know, "digitigrade" is just Latin for "walks on toes".
Answer: Sandals. Cats back legs claws don't rectract and hide like the front ones. So the footwear would need to allow them moving out when running or climbing. Also having 4 claws in the "foot" would allow to wear Ninja like footwear with a thong in the middle.
Answer: Will they wear shoes at all?
Wild cats don't wear shoes. Not all humans wear shoes. Poorer individuals, and ones living in the country (where they aren't walking on rocks and possibly sharp bits of discarded metal or glass) probably won't wear shoes at all, if indeed anyone does. Shoes will make it harder for your felinoids to use their claws. (OTOH, you can play that up as a social status thing, per Separatrix' answer.)
So... why might they were shoes? Aside from pure ostentation, shoes are useful for protecting paws (which are not as tender as you think if they aren't pampered) if your environment is unnaturally hazardous, which might be the case in cities, especially as industry starts to develop. It might also be occupation specific, e.g. I could see the blacksmith wearing boots (at least while working) even if no one else does. Shoes can also help keep water, or worse, off your paws. Part of the reason humans wear shoes is for "hygienic" purposes (although I wonder about this, at least in cultures that don't tend to take their shoes off indoors), although if your cats are still obligate carnivores, this is probably less of an issue for them.
In your setting, I would consider not just what shoes are worn, but when and by whom, because you will most likely have a mix of shod and unshod cat people.
Okay... so what kind of shoes?
We make shoes for dogs in a wide variety of styles, from very simple to ones that are just as complex as human shoes. (Cat shoes aren't as popular, but probably because a) it would be hard because of cats' smaller size, and b) indoor cats don't need shoes, and outdoor cats don't tend to get the same sort of completely unnecessary attention as dogs. Keep in mind that dog shoes are as much or more for the owners' benefit as for the dog's.)
There's no reason to think that a race of felinoids wouldn't be equally capable. Of course, you specified "a roughly medieval society", so leather moccasins and wooden clogs/sandals are more likely. Deliberately limiting use of their claws as a status symbol seems entirely plausible; this would be seen in more "gentrified" people, while those "closer to the land" (farmers, ranchers, hunters, trappers, etc.) will want to be able to use their claws.
p.s. Yes, you'll have farmers. They grow the stuff that food eats .
Comment: "Not all humans wear shoes" Depends on a climate. If winter is coming and one doesn't have shoes, it could be the last winter.
Comment: If a cat HAD a way to keep their paws from getting wet when it's rainy outside, you'd better believe they'd use it.
Comment: @Alexander, yes, but wild cats survive the winter without footwear. The difference of course is that they have fur. The OP didn't specify if the cats in question have fur or not, but if they do, they may be okay climate-wise.
Answer: Instead of using their own claws, as the other Answers suggest, I would think they would want to protect their claws and project a more pronounced claw.
City dwellers
If these cats are anything like humans, they will have some sort of inferiority complex, which of course extends to every part of them, including their claws. They would wear large faux claws on their shoes to hide their "inferior" claws, just like when a guy crotch stuffs or a woman wears a padded/lifting bra.
Because the claws wouldn't get wore down normally, they would require regular pedicures, which would also go to enhance their claws. This includes male cats, too. They'd have them filed down to sharp points, painted wild colors, and even have fake nail claw extensions.

Want substantial claws, go for the eagle talon. Or for those who want real class, our silver, gold, or platinum line claws are an absolute must!

FYI, gold, silver, and even platinum were used well before medieval times.
https://www.providentmetals.com/knowledge-center/collectible-coins/platinum-history.html
Rural folk
Just like the city people, these cat-folk would have the fancy go-to-meeting shoes that everyone else wears. However, they would generally have more rugged shoes to prevent accidents, for more padding, and for more actual grip.
These shoes would be considered work boots, which would include steel claws, rough leather, straps, water proofing, and hard rubber soles. The steel claws would not only protect against dropping things on their feet. They would also provide better traction, without wearing out or breaking so easily, and with the ability to be resharpened and replaced. The straps would allow for better binding to the leg, so the shoes don't strip off when needing the extra grip of the steel claws. And water proofing, because blech, water.

Our boots offer the latest in grip technology, which reacts to your own claws extending, shooting out an extra inch of claw to give you better traction when you need it. Get them in stainless steel, to prevent corrosion and to make cleaning easier.

Steel was also available before medieval times. Sure, stainless steel wasn't available until 1920's, but this provides a possible bridge to modern times.
https://en.wikipedia.org/wiki/Ferrous_metallurgy
Rubber was first invented in 1600 BCE, in Mexico, but who says the Americas weren't discovered earlier by the cat people? This is a fantasy story.
https://quatr.us/science/rubber-history-rubber.htm
Design
The shoes would be designed to hold each toe independently, so they would maintain the flexibility and balance a cat-person would require. Taller boots would include a cutout/spacing or pouch for their hind claw. Some shoes may include customized faux fur to blend in with the fur of the individual.
Of course there are small cats and large cats, so there would likely be heels and platform shoes, since some cats are just as vain humans and of course could care more about their height than their balance, just like humans.

Our Tigger(R) brand shoes give you the extra bounce and vivid colors you need to bring all the toms to your yard. You meow, girl!
Comment: Cat claws grow in layers; every now and then, the outer layer gets shucked off. Filing is *counterproductive*. They could easily have scratching boards that they run their toeclaws through every now and then to get rid of the outer layers.
Comment: @Matthew, from what I see, women don't really care about the position of their feet, they simply want to get taller, and better posture is a side effect. Whether it's because of "digitigrade" or whatever is irrelevant. Also, I've added a few things to address your other concerns.
Comment: While you have some interesting ideas, I am downvoting because much of your answer assumes a technology level that doesn't exist until modern times. The OP specified "a roughly medieval society". There is no rubber, no stainless steel, and dyes are limited. Also, if we're still talking about digitigrade critters, there will be no such thing as high heels; heels are a way of forcing plantigrade feet into a digitigrade posture.
Comment: I'm pretty sure that, for humans, trying to walk on your toes all the time is *worse* posture, not better. For cats, though, it doesn't matter; they're *already* standing on their toes; their shoes may not even extend to the heel, much less have devices on the heel intended to make them "taller". (Platform shoes might be plausible, though again, I can't recall those existing in the middle ages. To an extent, that degree of vanity is a product of modern luxury.)
Comment: @Matthew, you might want to look at image searching for "medieval shoes". There's a lot of even "commoner" footwear that includes extra long or curved toes, as well as lace-up thigh boots. Then there's https://world4.eu/medieval-shoe-king-john-ii-france/, which includes "platform" risers. Since they are anthropomorphic, they'd also walk on only the hind feet, so height between races would be exaggerated even more. Wouldn't a ruling Mau want at least some height gain on a General Lion?
Answer: Depends on the season
In mild or warm weather, cat people would were shoes that expose their claws, or wear no shoes at all (although the latter may be viewed with disdain). Other answers had suggested a number of options for that, like sandals.
In cold weather, or when the roads are particularly dirty, shoes with openings are becoming a trap for water and dirt, making them very impractical. If dirt is the only issue, very open sandals might do, but as the temperature goes below freezing, closed shoes is the only option for a "civilized" individual. Cat people would have to sacrifice their ability to use claws and wear human-like boots with no openings at the bottom.
Answer: Probably something like ballet shoes, with slits for the claws. As others have said, their back claws don't fully retract and they do use the claws for improved traction etc.
If your cats are anything like RL ones though, they will hate wearing them!

Footwear for cat-people


401K loan repayment Default

Question: I have a 29,000.00 loan from my 401K That I am paying 800.00 per month on. My wife has been ill for 2.5 years and unable to work. Currently trying to get disability. However this has created a big burden on us. Can I stop paying on my loan and absorb the fee and tax burden. If I can't do that than bankruptcy is my only other option? Can this loan be included in that?
Comment: If you're heading to bankruptcy, pay back this loan, then declare bankruptcy.  Tax deferred retirement accounts generally enjoy protection from bankruptcy, though it's possible a bankruptcy court might undo recent transactions.
Answer: Generally, 401k loans are loans you made to yourself. So you can stop paying it, default on it and it will be considered non-qualified distribution to you (you'll pay income tax on the amount unpaid + 10% additional penalty + whatever fees the 401k provider charges).
However, if you're still employed, the loan payments may be taken automatically from your paycheck and it may be that you cannot avoid that without actually quitting - check with your employer (some 401k plans don't allow distributions as long as you're employed).
As mentioned in the comments, the ERISA allows very broad protections for retirement accounts in case of bankruptcy. So while you should talk to a bankruptcy attorney about this, the general rule is that it is better to have as much stashed away in IRA/401k accounts as possible before entering bankruptcy proceedings - because that would be the only reserves left to you.

401K loan repayment Default


How to manually link existing records for Saleforce-to-Salesforce

Question: I have Salesforce-to-Salesforce set up and working (with automatic sharing etc). It works great for go-forward records.
I'm struggling to find out how to deal with existing records that exist in both orgs.
As an example, if I spin up 2 brand new Dev orgs and connect them with Salesforce-to-Salesforce, I end up with duplicate "Edge Communications" in the Partner org. I want them to be the same (not looking for real-time fuzzy matching, I'm ok doing the work of linking them individually)
How can I manually link the 2 accounts together?  I'm looking at the PartnerNetworkRecordConnection docs and see that there is PartnerRecordId, though this field is not writeable.
A bit of background
We have an old crusty Salesforce org with a bunch of complex integrations set up. We are building a nice new shiny org that we want to be the go-forward place to do things. As part of our migration plan, there will be a period of time where Sales will be working in the shiny new place and we can't just move over the integrations, thus S2S to push over just what the integrations need in the interim.  To make this work, I think we will export from the crusty org all the data, and import into the new shiny org the cleaned-up data. We can maintain relationships as needed etc to help with the problem I have posted about.
Answer: There's no good way to do it but if the records are mergeable, you can share the record and then merge it with the duplicate in the partner org. You must keep the newly created record because its Id will be in the PartnerNetworkRecordConnection object as the LocalRecordId and so you want to keep that Id intact. We do this a lot with Accounts.


Why there is not a community for embedded in stackexchange?

Question: I think its not a place to ask this question but Why there is not a community for embedded in stack exchange. In stack exchange, every type of topics subjects & communities are available but not for embedded systems.
Comment: What kind of question about embedded systems you could not ask here?
Comment: define embedded
Answer: A private beta for a new embedded SE was launched recently, but it will be shut down on Friday, August 14. The explanation for this is only available to members of the private beta group, so I will reproduce it here in full.

About a year ago, we closed a previous attempt at starting a site for
Embededded Systems. At the time, the problem was there just wasn't
enough activity to sustain a healthy site. Since then, we've put a lot
of thought into what we expect of sites during the "beta" period.
After considerable research (primarily by Ana and Pops, but with the
input of the entire team), we determined that there is no particular
harm in allowing sites to continue operating with very little activity
as long as the community curates it's content. As a result, we are far
more reluctant to close tiny, but otherwise established communities.
On the other hand, we are more reluctant than ever to launch sites
before they've gathered momentum to carry them through the inevitable
post-launch lull. Users tend to drift away from sites that don't
provide a constant supply of interesting questions and we've found it
particularly difficult to recruit capable moderators for inactive
sites. Slow starts in private beta invariably result in nearly static
questions pages. Long-running betas also block new proposals that
could be counted as duplicates.
Currently, this site has 74 questions in 9 days. While that would be a
pretty good clip for a mature site, it's slow for a private beta:

Note that 20 questions on the first day is a little low and the rate
drops from there. Inevitably, activity slows over the weekend, but the
activity this week has barely rebounded at all.
As with the last iteration, we don't have any problem with the content
this site has produced. It's pretty clear that you all are very
knowledgeable in this niche topic. There's just not enough activity to
sustain a thriving Stack Exchange site. It's hard to know why this
topic, which fits quite well with our core audience of developers,
can't gain traction. Perhaps the problem is that embedded systems
questions already get asked around the network. According to my
estimation, the embedded tag on Stack Overflow gets good, timely
answers:

<code>TagName  N    median_views avg_score closed_rate avg_answers accepted_rate answer_rate median_tta
-------- ---- ------------ --------- ----------- ----------- ------------- ----------- ----------
embedded 4825 409          2.7       6.9         2.3         55.4          90.4        53
</code>

Looking at recent technology betas the most successful sites focus on
well-defined communities such as elementary OS, CiviCRM, Vi and Vim,
and Emacs users and developers. It could be that embedded systems
professionals identify themselves primarily as programmers and
engineers.
Whatever the reason, this site will be closing on Friday, August 14.
Please take a moment to identify exceptional content that could be
migrated to an existing site so that it can be migrated. As always,
all content (including migrated questions) will be available in the
data dump released shortly after the site closes.
Thank you for all your hard work proposing, defining, committing, and
contributing to this beta.
asked Aug 6 at 21:24
Jon Ericson ♦

Several people objected to this decision on the grounds that nine days is not enough time to judge a site, especially during a popular vacation time for the Northern Hemisphere.  Robert Cartaino ♦ answered this in two comments. First:

To folks asking about the summer traffic levels — I looked at similar sites (electronics, robotics, etc) and the traditional summer drop off is maybe 10% (if I'm being really generous). Our sites launch at all times of the year, so the numbers Jon cites above would have taken that into account anyway. But even if we accounted for the summer drop on an adjusted basis, the drop off is not enough to overcome the shortfall in participation. It just wouldn't have made a difference.

Second, in response to a question about whether the shutdown could be averted:

120 high-quality questions by Tue, 8/11 would be cause to reconsider. But it would have to be sustainable, organic growth from an untapped audience; a few users pulling an all-nighter wouldn't help. I know it's tough to judge "success" by the numbers, but the correlation between a slow start and sites that never gain traction is SO strong, ignoring those hard-earned lessons is becoming increasingly irresponsible on our part. It's a good subject; every fiber of my being is screaming "gawd, this site SHOULD work!" But we've got to own up to it; we didn't pull it off this time.

Our own Scott Seidman has been through both attempts at launching an embedded systems SE, and offered his opinion:

I have to add that the first launch seemed much more successful, and that the decision to close it then to help it build more momentum for a relaunch seems to have failed. I think the first go-around could have found a flame, but I don't think that this one can.
Also, comparing to other successful tech stacks doesn't make sense unless you normalize to potential user base.

Scott also posted a Meta.SE question where he discusses some of the problems he sees with the beta site launch process. It's visible to everyone, so I won't reproduce it here.
Answer: The Area 51 page explains what issues the site had.
Comment: [Area 51](http://area51.stackexchange.com/) is the proposal site for Stack Exchange sites. It needs to pass through there before it is created.
Comment: @Nick apparently not much longer unless there's a change of mind: http://meta.embedded.stackexchange.com/questions/69/closing-this-site-on-friday-august-14 (personally I thought it had too much crossover with EE, SO and others)
Comment: There is a [2nd attempt at Embedded.SE](http://area51.stackexchange.com/proposals/70800?phase=beta), which is in private beta at the moment.
Answer: Obviously this is not a place to ask such questions. Embedded is purely electronics with programming so you can directly ask questions of your embedded in electronics community.
Comment: I disagree. Embedded is on (and over, on both sides) the boderline between electronics and programming. I have seen questions that are prefect for embedded being migrated from EE to SE.
Answer: Emb. programming is "hardware" programming.... When you programm a MCU, a DSP, etc.. the level of abstraction is very low, therefore, it depends more on electronics design knownledge... The EE exchange can give support these questions.


Make edges of anti-aliased selection semi-transparent in Photoshop

Question:
So I have a path from which I create an anti-aliased selection of that arc-shaped object and paint it a solid color, red in this example. If I then want to change this color (to light gray in example) I get leftovers from red on the edge of selection and to get rid of it I have to paint with the background color over the edge with selection inverted.
I should note that both dark-gray and red are on the same layer.
I assume Photoshop paints beyond the selection to create an anti-aliased effect. Is there a way to avoid this efficiently while maintaining anti-aliasing?
Answer: Change your workflow
The problems you are encountering can effectively be avoided if you start working in a more layered fashion.
I recommend using separate Solid Color layers with Layer masks.

This way you keep color and opacity separated so you can easily change one without affecting the other.


Proto-Indo-European protowriting?

Question: The Mesopotamians had their own writing system. The Mesopotamians are said to have invented the wheel. The reconstructed vocabulary of the Proto-Indo-Europeans indicates that they had wheels. There is no vocabulary that I know of that indicates writing (they could have a word that means "to record" or something like it), but the way that the wheel spread made me think the Proto-Indo-Europeans had a simpler, older version of cuneiform.
Comment: What exactly is your question? Whether there's any evidence of this?
Comment: Could the Mesopotamian writing have been originally Proto-Indo-European?
Comment: perhaps they had no need for message writing, if whoever delivered the message could simply tell it.
Answer: A number of people lived in Mesopotamia, including the Sumerians, Kassites, Akkadians, Amorites and other Semitic-speaking people, and Persians. Cuneiform writing was invented by the Sumerians, and widely adopted by many cultures including the Iranians and the Hittites (and their kin), a number of years later. But Indo-European presence in Mesopotamia (which is different from Anatolia) is a more recent and limited historical development. It is implausible that they had a writing system which left no trace, inspired the Sumerian development of their hieroglyphics (whence cuneiform), then re-adapted it millenia later when the Hittites picked up this writing system from Assyrians to the south-east.
Comment: I don't see why a) "It is implausible that they had a writing-system which left no traces ...", although most materials detoriate rather quickly; also, there's Vinča symbols (c.p. Tamga). Writing is not necessarily textual. b) "... inspired the Sumerian development ...", e.g. in the so called Proto-Euphratic hypothesis. lulz c) "... then re-adapted it millenia later", one-and a half, not that many, stranger things have happened. Other than that, I wouldn't dare to call you wrong.

Proto-Indo-European protowriting?


Block single page with NoScript?

Question: I use a page with a very annoying alert onLoad, I'd like to block JavaScript on that site (it's http://example.com/home.jsf), but I need JS to use the rest of the web-app.
Can I block scripts only on home.jsf?
Answer: It's not the most intuitive of things, but you can do it using NoScript's Application Boundaries Enforcer.
I explained how to block just Google Search's Javascript (to kill Google Instant without logging in while still allowing easy login and use on other Google sub-sites) at How to make Google Search scriptless with NoScript/AdBlock?
You can also use it to lock scripts from sites like Facebook into the domain they come from, so scripts from Facebook will only load if you're actually on Facebook. (Good for killing off stuff like "Like This", "Tweet This", and Google Buzz buttons so you don't have to trust them as far as your privacy and browser responsiveness go):
# facebook.com containment rule
# This rule allows Facebook scripts objects and frames to be included only
# from Facebook pages
Site .facebook.com .fbcdn.net
Accept from .facebook.com .fbcdn.net
Deny INCLUSION(SCRIPT, OBJ, SUBDOC)

# twitter.com containment rule
# Like the Facebook rule, but for twitter
Site twitter.com .twitter.com twimg.com .twimg.com
Accept from twitter.com .twitter.com twimg.com .twimg.com
Deny INCLUSION(SCRIPT, OBJ, SUBDOC)

# Google Buzz containment rule
# Like the Facebook rule, but for Google
Site ^https?://www\.google\.com/buzz/.*
Accept from google.com .google.com googleapis.com .googleapis.com
Deny INCLUSION(SCRIPT, OBJ, SUBDOC)

Answer: I don't know if you can do it with NoScript, but you might be able to do it with  GreaseMonkey by replacing the function or clearing the onLoad.
Comment: i think GM is fired after the page has already loaded, can I really stop this alert?
Comment: The [GreaseMonkey uses DOMContentLoaded](http://wiki.greasespot.net/DOMContentLoaded) ; this fires before `window.onLoad`, which doesn't fire until after the page is finished rendering ... I haven't tested to verify, though
Answer: You should be able to using the blacklist functionality. As opposed to the usual whitelist of sites that you allow.
Answer: NoScript deals with "domains" rather then pages.
Generally no, [url=http://forums.informaction.com/viewtopic.php?f=7&t=5468]Possible to enable scripts on one specific page?[/url].
Though there are a lot of "other" features that NoScript offers that may help (just don't ask me which, though I do seem to recall some discussion of an annoyance on a particular banks website.)
Comment: The formatting language used here is [MarkDown](http://daringfireball.net/projects/markdown/syntax), so the inline syntax (not using footnotes) is `[link text](url)`
Answer: Try AdBlock Plus.
I presume you have the addon already. Use "Open Blockable Items" to select and create a filter. Along with ABP Element Hiding Helper, this is how I clean up over-cluttered pages.

Block single page with NoScript?


Does the pump for a water tank have to be next to the tank or some distance away?

Question: Does the pump of a water tank have to be next to the water tank or can it be further down the line?
Comment: What type of pump and water tank are we talking about? Hot water tank recirculation pump, boiler, solar tank, rain barrel, or a rooftop water storage seen in places like India? Will the pump be located below the water tank in both situations?
Comment: It can be wherever you like, but the closer it is, the less it will cost in piping.
Comment: It also is necessary to understand whether the pump is used for filling the tank or emptying it.
Answer: Assuming we're talking about a well here.
In a well system you need a pump to get the water out of the well and an accumulator tank to store it so the pump can fill the tank against some sort of air space for pressurized storage so the pump doesn't run all the time.
Submersibles may be in a 400ft well, or in a shallower well with either submersible or jet pump, but across the lot. What matters is that the pressure tank is in an enclosure to protect it from freezing and that the pressure switch be in the pump-tank circuit before the system shutoff valve.
Yes, the pressure tank can be displaced quite a distance from the pump; either by depth of the well or convenience of placement for the tank due to climate constraints.

If you're talking about a stock tank or other unpressurized system. The issue that matters is you have a level switch that works to turn the pump off. The constraint is the cost in running the pipe and power losses in the electrical cable are what would determine how far away the pump can be located.
Answer: The bladder pressure tank should be as close as possible to the pump to avoid short cycling issues .No ,if ands or buts.


Assign large numbers of activities at once - Wordpress

Question: Is there any way of doing this from the interface. I have lots of activities that need to be assigned to a small group of individuals. I want to assign these (currently unassigned ) activities to the corresponding contact. Can't do it through batch update or import, the assigned field isn't exposed.
Comment: worth stating what CMS you are using to help get/avoid answers like mine ;-)
Comment: Couldn't you use the api (through ui (/civicrm/api))?
Answer: If there is a way, we didn't find it, and that was partly why Fuzion put a bunch of time in to making it possible to assign/unassign/reassign Activities in Drupal using CiviCRM Entity Actions which is now a submodule of CiviCRM Entities, Views and Views Bulk Operations, in order to deliver a Calling Tool that could be driven from the Drupal front end. (Is there some way I can mark these types of answer as Drupal-only info?)
Comment: That would work, but as you said, I should have stated the CMS, which is unfortunately Wordpress
Answer: Since you mention import you could try using the csvimporter Extension, which does include many other Entities such as Activities and provides fields for eg 'assignee' when doing so.


Are there any online resources, such as courses/tutorials/blogs, about UI/UX sketching?

Question: So, I've read Sketching User Experience by Bill Buxton and several blogs discussion how to start the ideation process in a good way with sketching. I've also read about different pens, such as Copic and Sharpie, and seen showcases of UI sketches. But, nowhere have I found any resources about actually becoming better at the sketching craft specifically for UI/UX. Are there any?
Comment: To clarify, I am looking for a tutorial of some sort, telling me like "you should use shading like this" or "draw the lines twice for emphasis" or "this is a good way to sketch a button so that it looks like a button".
Comment: What I am looking for is resources about "manual" sketching on "analogue" media. ;-)
Answer: This might be relevant for you: 5 tips on sketching user interfaces:

Draw box-elements with four separate lines — do not try to draw them with one continuous stroke.
Use drop shadow to distinguish graphical elements.
Use a thick sharpie to focus on loose form rather than details.
Get your arm off the paper: you'll draw with your shoulder rather than with wrist and your lines will be straighter.
Constrain yourself: do not focus on details, set up deadlines and maybe try to sketch on post-it notes

An additional useful resource The Messy Art Of UX Sketching by Pieter Buick, covering topics and tips such as

Work in Layers
Loosen Up
Play To Your Strengths
Sketching Interactions
Copying And Pasting For The Real World - Use a photocopier
The Design Is In The Details - Use a ruler
Tell The Whole Story
Ditch The Sketchbook

Eva-Lotta Lamm also has a great presentation on Speaker Deck on Sketching Interfaces and also describes her list of favourite equipment.
Comment: I can now add one more tips to that list, after finding this: http://www.youtube.com/watch?v=4szf2FTaVU0 - Always rotate the paper, do not change the position of your hand.
Comment: Yes, thanks for linking directly. Now, that was a good start, I will practice this a lot ... so, where's the rest? :)
Comment: And, from the youtube-clip as well, the shading technique he's using is great. Doing that in an interface sketch would add real depth.
Answer: Here's a blog post that has some ideas:
http://www.uxbooth.com/blog/tools-for-sketching-user-experiences/
There's a Flickr group, though I don't know if it's being moderated anymore:
http://www.flickr.com/groups/uxsketches/pool/
And Jakob Linowski has a lot of great posts on hand sketching:
http://wireframes.linowski.ca/
Personally, I'm a fan of simple tools:

pencil for quick sketching
thicj and thick black markers for clean-up
a few primary colors for noting interaction (red, yellow, etc)
Answer: I might be reading this wrong, but there seems to be an implicit assumption here that freehand sketching practice must be achieved through analogue means. If you have access to an iPad and stylus, I can heartily recommend the Brushes or Penultimate iPad apps as a way of getting better at sketching freehand. I had almost totally abandoned sketching on paper because I was getting increasingly frustrated with the lack of an Undo command and the general messiness of erasing and/or starting again, then I was lucky enough to have use of an iPad for a while, and it totally changed how I related to sketching — it became a real pleasure.
I have the Griffin iPad Stylus: it's cheap, very nice to use, and good all the way down to one or two pixels in Brushes, though for Sharpie-type sketching I tend to use Penultimate, which has much better detection for quick pen-strokes.
The stylus also works pretty well with Brushes on the iPhone, though obviously you have less screen to play with there. But it's still good for doing stuff on the fly.
Anyway, hope that's helpful.
Comment: Good point. I do have the Griffin stylus and Penultimate, as well. Even if I have the tools, analogue or not, I still feel I lack some skills in sketching though. :/
Comment: Yeah, I know what you mean. I think it's just about practicing and practicing and eventually you get better and/or it starts feeling less weird. Good luck! :)
Answer: I think there's only one way to get better: Practice, practice and practice.
Comment: Oh yes, but it would be nice to get some pointers (no pun intended) in the right direction.
Comment: Ok, I should have read your short bio before, didn't know that you already have years of experience. Good answer by Roger though - he got my vote.
Comment: No worries. You can always blame the UI for not pointing that out in a better way. :)


EXPIRY OF ABANDONED CART

Question: Is there any configuration to control the expiry of abandoned cart in the admin section in abandoned cart report?thank you
Comment: You mean you want to remove to remove abandoned carts after certain time?
Comment: right! is there any configuration in the admin for that?
Answer: This feature is called managing quote lifetime.
There is a configuration in admin panel at Stores => Configuration => Sales => Checkout => Shopping cart => Quote Lifetime (days)
Here by default it is set to 30 days which means quotes which were not updated in last 30 days will be removed.
The cronjob sales_clean_quotes which calls method \Magento\Sales\Cron\CleanExpiredQuotes::execute will remove these quotes from the database. Please note that it will not be only removed from abandoned cart report, these items will be removed from the customers cart as well according to the configured quote lifetime.
Comment: Thank you for your response, if I understand well, if I change Quote Lifetime (days) to 2 per example, I will lost the abandoned cart report in 2 days, right?
Comment: Yes. Also, customers will not see items in cart if he has not updated cart (add/edit/remove item) in last 2 days.

EXPIRY OF ABANDONED CART


A Book of Neat Theorems for Laymen

Question: I'm looking for reading assignment ideas for my students.  I'd like them to read up on results in mathematics in layman's terms.  For example, the Monty Hall problem, or Borsuk Ulam as the "Ham Sandwich Theorem".  I feel a good source for the types of things I'd like them to read is this post.  I would have each (group) student do a write up on a particular subject.  Does anyone know of any books that give a list of results that are understandable for a calculus student?
Comment: Proofs from the book. Martin Aigner, Gunter M. Zeigler. This is not exactly what you are asking for, but this is an amazing collection of proofs which everyone must see.
Answer: Journey through Genius: The Great Theorems of Mathematics, William Dunham.  Definitely within the grasp of calculus students (maybe too easy?), and contains discussion of twelve classic theorems.  The theorems come from throughout the history of mathematics (from the quadrature of the lune and Archimedes' calculation of circular area to Cantor's proof of the uncountability of the reals), so it also provides a nice perspective on some of the most famous mathematicians.  I loved this book when I first read it in high school.
Answer: Thougher going than Dunham's books (very higly recommended!) is Aigner-Ziegler's "Proofs from THE BOOK". Consider also Pólya's classic "How to solve it", it shows not finished results, but how to go from the problem to a clean solution.
Answer: The Mathematical Universe: An Alphabetical Journey Through the great Proofs, Problems, and Personalities, by William Dunham.
Answer: $Q.E.D.$ is a cute, compact, little book of proofs easily found at Barnes and Noble.

A Book of Neat Theorems for Laymen


When and how should a philosophy student start to give his/her own ideas?

Question: I am not a philosphy student, but I am a philosophy enthusiast who loves and studies philosophy on his own. I completely understand what philosophy books are trying to say, but I dont know how and when should I figure out my own ideas. When am I allowed to give a new philosophical idea and how should I just figure out an idea about a philosophical question/writing?
Comment: Allowed?  Who's going to stop you?
Comment: To add to this - the first step is to read. Read, read, read, and read some more. Read every philosophical work you can get your hand on, from as many fields and streams as possible. You'll find yourself agreeing with some things more and more and developing a philosophy, almost as a natural process.
Comment: Start now. It will take a while to find a publisher, but start now.
Comment: When you are sufficiently informed about the topic you want to address, so you don't make mistakes others already made. For that, you need to read, research, investigate, ask, etc.
Answer: The core to developing a position of one's own is reading as much as possible. One of the lecturers back in Kent suggested as much as six hours daily, but I consider this as upper end. I'm a fast reader and could do well with way less.
The reading has three effects: Firstly, you become acquainted with historical arguments and ways to argue, so you do not try to come up with arguments long defeated out of pure ignorance. Secondly, you are able to think, talk, and write about various problems much more nuanced as you know the arguments and problems as well as various approaches. And thirdly, you will eventually find yourself agreeing with some positions in general and some arguments in particular, which automatically leads to a position of your own.
Two points to be aware of: Firstly, with great philosophical works, if you read them carefully and try to understand the arguments instead of rejecting them right away, there is an effect that you will find yourself agreeing with whatever you read last. This is not persistent but a thing to keep in mind. Secondly, chances that there is any argument or point you come up with that is absolutely unique and nobody ever having had this position before are practically non-existent. That is something you realise when you read a lot. It is not a bad thing as such, though. You can still come up with an inherently better way of presenting the same position.
As of when starting to make a point of your own: Generally, even with bachelor essays, a perfect grade requires some original input of yours. In the bachelor thesis and masters studies it is expected that the original input goes far beyond the way of presenting. The ability to present the relevant literature and a nuanced argument that includes critical reflection is always the core of any good writing in philosophy studies though.
Comment: Would +1 for this paragraph alone:
Two points to be aware of:...
But this is still a great answer
Answer: You are at the right place: This blog has questions and answers referring to all themes in philosophy!
I reommend to browse the tags for a first information. You can choose some subject which interests you most. Then you may choose a few corresponding questions from the blog and write down you own answer. A good answer uses clear terms, formulates precise arguments and focuses on the subject. You will find some help via the "questions" button - also valid for answers.
As soon as you get some feedback from other users you have entered the philosophical discussion. Now you can test your ideas.
In parallel it is necessary and indispensable to read the primary sources. Which works could be the top ten on you personal reading list?


If I exposed my public view key and public spend keys, what gets compromised?

Question: If I expose my public view key and public spend key, what can someone do with it?
Answer: Your public view and spend keys are already disclosed - they are parts of your standard, public address. All someone can do with your address is send you funds. Of course, anyone you disclose your address to will know you use Monero, they will not however be able to view any of your transactions.
Answer: Someone who gets your public view and spend keys can:

send you money

Your public keys are basically your standard address, so you're giving them out when you hand someone your address.

search for this address in any set they have

If someone obtained, say, a set of addresses used to withdrawn from an exchange, they can determine whether you ever withdrew from that exchange using that address. Using subadresses fixes this, since they're meant to be one off use.
Things they CANNOT do include:

check a block explorer to see that address' balance

Nope noppety nope. With Monero, you keep your privacy. People you give your address to have no business knowing your balance nor your transaction history

steal your money

It's public keys. If they have your secret spend key, that'd be another story.

Determine your secret keys

Public keys are created using a one way function from the secret keys. You can't "go back" up the derivation.


When a research statement of a fixed page length is required, are references counted in the page length?

Question: On mathjobs.org, a few jobs request a research statement of no more than 3 pages. Are reference pages typically counted for such requirements in the United States?
Comment: I would think you would need to ask the individual departments about this. However, I also suspect that departments don't want to limit the amount of room in such an important document based on the number of references you have. So I'd guess that you have three full pages of text (references shouldn't count).
Comment: Just for reference, in the EU the references are included in the limit, at least some of the time.
Answer: Unlike the NSF, where references often do not count towards page limits, I would assume that references do count as part of the 3-page limit for a research statement in a job application.
At the same time, few research statements I have seen in mathematics are as thoroughly referenced as an NSF proposal. The main goal of a research statement when applying for a job is to describe your own research and to demonstrate that you will be able to meet the research expectations of the job. As such, you want to keep the research statement relatively brief.
If you really need more than 3 pages including references, you should email the chair of the search committee to find out if it is acceptable.
Answer: Generally speaking, no.  Two reasons:

Nobody reads the references.
It is unethical to penalize the author for giving credit where it is due.

That said, an HR staffer may not know about academic practices.
Comment: _Nobody reads the references_ — **False.** I read the references.
Comment: _It is unethical to penalize the author for giving credit where it is due_ — This is a red herring.  The constraint is not "don't give credit" but "keep your entire document under 3 pages".


momentum conservation related to varying mass . please help?

Question: a heap of chain is lying on a horizontal table a small part of the chain is released through the hole in the table . Calculate the velocity of the chain as a function of length of the vertically hanging portion
Answer: We don't need to account for the mass
S: Distance
t: time
a : Acceleration
g : 9.81
$S(t) = \int \int {a} dt dt$
$S(t) = \frac{1}{2}a t^2$
The constants of integration are zero since the object starts at rest.
We could just use $g$ for the acceleration or we could include some drag constant $k$
$S(t) = \frac{1}{2} (g - k) t^2$
$t = {(\frac{2S}{a})}^{0.5}$
$V(t) = gt$
$V = g{(\frac{2S}{a})}^{0.5}$
or
$V = (g - k){(\frac{2S}{a})}^{0.5}$ if you prefer to include a drag constant
Comment: The acceleration of the chain will vary as a function of the force acting on it due to its own weight ( which also keeps changing ) . i.e the hanging part.
One can't simply take it as g let alone putting a cherry on top like (g-k)
Comment: the force acting on it is g, which does not change unless you move to a different planet
Comment: g is called acceleration due to gravity  or gravitational field intensity if you can comprehend .
Force  on  anything by the virtue of it is called gravitational force  : which is mg.


How to format a variable of double type

Question: I have a variable of double type representing a value of about 34.323423423123456. I'd like to format it to have only two decimal places (e.g. 34.32), rounded properly; e.g. 2.229934345 would become 2.23.
I am new to Java and none the tricks I know from C# worked.
Answer: Related to this Question use DecimalFormat setRoundingMode
Answer: Here's an example format string, I believe it correctly rounds the resulting value.  See Markus' post if you need more control over the rounding or format:
<code>String.format("%.2f", 2.229934345);
</code>

How to format a variable of double type


Mesh added to scene is off axis

Question: I am very new at this and I'm not entirely sure how to explain this stupid and I'm sure easially fixable problem... I have the cursor and origin set to the center. But when I add mesh like a flat plane, it is added facing flat to whatever my view is instead of adding at 0x 0y 0z. So to add a plane flat with the grid, I have to be in top view (7).
Comment: okay, so, what you have to do is hit f6 AFTER adding the object and uncheck Align to View. you can also access these options at the bottom of the Tools Shelf (if you don't see it, look for the + sign at the bottom and click it). hope this solves your problem :]
Comment: Yes, and as of 2.8 default keymap it's now F9 instead of F6 (for some reason)
Answer: Right after adding your object, uncheck the [   ] align to view option in the toolbar. If you don't see the toolbar, hit t and it will pop up on the left side of the 3d view.
Edit --
Just to add Zac's comment: you also can access this menu by hitting F6 after adding your object.

Mesh added to scene is off axis


what is bandwidth?

Question: this word is confusing me, i know its data rate that a wire can carry, but still i am confused about this concept. please explain it in more understandable form. Any answer in simple words would be preferd.
Comment: distance/time:speed::datatransfer/time:bandwidth
Comment: (moved:)
In an unfortunate misapplication of the term, you'll also find some providers use it to mean the total amount of data you transferred (or that they allow you to transfer) during a billing period, which is more properly described as total transfer or transfer quota, respectively.
Answer: I think the best basic analogy for someone to understand is using water as metaphor.  The amount of water that can be transmitted through your kitchen faucet is less than a firehose can push.  The size of the pipes determine how much water can pass through.  This is roughly equivalent (in layperson's terms) to the idea behind bandwidth.
Comment: Water and pipes is a very popular metaphor.  It has even been discussed on the Senate floor.
http://en.wikipedia.org/wiki/Series_of_tubes
Comment: hehe Gotta admit getting linked to the infamous "series of tubes" guy stings a little, but I still think it's something very tangible that people grasp very easily. I've also had a professor use the "water metaphor" to explain basic concepts of electricity (which I also thought worked pretty well).
Answer: Are you asking about the origin of the word ? If you, you need to dive a bit into signal theory.
Information is transmitted by modulating a signal. A signal is "something" that changes over time. You can describe it with all the values it takes at different times; or you can look at its Fourier transform, which gives you the spectrum of the signal. The spectrum tells you which frequencies the signal puts energy in.
When you send a constant signal, over a single frequency, its spectrum is a single vertical line. Also, since the signal is constant, it cannot transmit information.
When you modulate this signal at a certain rate (on/off, phase reversal, fsk, whatever), the spectrum becomes wider. That means the signal puts energy not only in its base frequency, but in the neighboring frequencies as well. (This is because modulation (multiplication) in the time domain corresponds to convolution in the frequency domain).
A range of frequencies is called a band. The bandwidth of a signal is then the width of its spectrum, or the range of frequencies it puts energy in. Bandwidth is linked with the theoretical maximum data rate of a signal: the faster you modulate, the wider the spectrum.
While the troughput of a signal gives you the rate at which you can transmit data with it, its bandwidth indicates how much of the spectrum your signal is occupying; this is important, since signals that have overlapping bands will interfere with each other.
Answer: I'm not sure how much simpler of an explanation you can ask for. It is how much data can be transmitted through a medium over a period of time.
If you can transfer 1Mb every second, your bandwidth is 1Mb/s.
It's a relatively basic concept.
Comment: What you have described, while colloquially known as bandwidth, is more correctly known as throughput.
Comment: @eleven81 - Bandwidth is the theoretical maximum for a given medium, throughput is the real world performance. I fail to see your point.
Comment: "Bandwidth" originally referred to the range of frequencies used in an electromagnetic communication signal, but it has in the last 20-30 years been co-opted as a synonym of "Throughput". At least it's less intellectually offensive than the use of "Organic" to mean "grown without pesticides". I always wince when I hear people use "organic" that way.
Answer: Bandwidth is essentially a capacity. i.e. How much data you push can onto the pipe/cable per second. The bigger the pipe, the greater the bandwidth.
Bandwidth is not the only determining factor in determining a connection speed. You need to know the "Latency" as well. Latency is delay. i.e. How long does it take for a packet of information to go to a location and come back.
Here is an example of a system with High Bandwidth and High Latency:
Lets say you had a 2 GB flash drive tied to the foot of a pigeon. The pigeon delivers the flash drive to the end location and comes back in one hour.
The bandwidth of this system would be 2GB per second (assuming it took you a second to tie the flash drive to the pigeon), since you could push 2GB of data at once onto the pigeon. The Latency would be 1 hour. It is how long it took the pigeon to fly to the location and come back.
In essence a good connection will have high bandwidth and low latency.
Answer: Wikipedia (Simple) to the rescue!
http://simple.wikipedia.org/wiki/Bandwidth_%28computing%29
Answer: In computer networking and computer science, bandwidth, digital bandwidth, or network bandwidth is a measure of available or consumed data communication resources expressed in bit/s or multiples of it (kbit/s, Mbit/s etc).

what is bandwidth?


In CentOS, when using Simple Control Panel, how do you access a newly created domain? via IP

Question: In CentOS, when using Simple Control Panel, how do you access a newly created domain? via IP
edit:  I actually meant to say, where / which file holds the domains / aliases for those domains set up in SCP? Thanks!
Answer: Easiest thing to do (assuming by "new" you mean, not yet setup in DNS) is to change your local /etc/hosts file to point to the IP address by the domain name in question.  This works in Windows or Linux or Mac OSX just fine
Comment: Hmm, this might be a bit different.  I actually meant to say, where / which file holds the domains / aliases for those domains set up in SCP?  Thanks!
Answer: I was actually able to find out that SCP creates a virtual name CONF file in the httpd directory.  This is where you'll need to go to modify that name.  Under: Turbo*conf


How to connect to a PC in LAN from the Internet (No static IP)

Question: The PC (Raspberry) is in a LAN Network and I want to connect to it, however the network doesn't have a static IP.
Additionally I can't use Port forwarding and Dynamic DNS.
What other options do I have?
Answer: Since you cannot connect to the Raspberry, your only option is for it to connect
to you.
You need to set up a VPN server, reachable via the Internet, and have the
Raspberry connect to that server.
Your computer can then also join that VPN network, for the Raspberry to become
accessible.
Beware that in a corporate environment this may cause some alarm,
so better get first the required authorization.
Answer: Not easily.
Its worth remembering that packets from the outside wouldn't know how to reach you and working between two dynamic endpoints is... challenging. Assuming you're using a raspberry pi cause its cheap - spending extra money isn't really an option.
Essentially this problem seems identical to trying to connect to a system inside a carrier grade nat.
The solution is basically "If you cannot connect in, connect out" and establish the connection from your system. Which is tricky if your endpoint dosen't have a staticish, routable IP
There's a bunch of possible solutions - find a service like ngrok if its just a web server that handles the connections for you.
Some time back I'd have suggested ipv6 - I used to use a defunct tunnel broker provider that worked behind a nat - if you can find a provider that works for you
(or its supported by your endpoints), its probably the 'neatest' way to get this working.
You might also be able to use a third party VPN that works behind a nat. Back in the old days, we used to run lan games over the internet  using hamachi - though zerotier seems to be a more modern alternative. They do have a fairly reasonable free tier.
Basically - any options you have will be limited, involve a fair amount of extra work or cost.


How to select resistance to cancel offset output voltage due to bias current?

Question:
Consider the figure above how Rcomp was choosen. I know for simpler circuits
like inverting amplifier and ideal integrator how Rcomp was calculated but following same procedure (that's using superposition principle for Ip and In and then convert to Ibias and Ioffset) here gives a time variant equation of single time constant circuit I don't know how one can cancel offset due to Bias current in such equation.
Comment: If you haven't already, watch this EEVBlog video where Dave explains about opamp's input bias currents: https://www.youtube.com/watch?v=TxBJb-Z0XFI&t=1s
Comment: DC bias not not time variant, but for AC, CMRR from external components demands matched differential source Impedances.
Answer: Bias current and offset are both DC phenomenon.  The way to deal with a capacitor for DC analysis is to treat it as an open circuit (and in the unlikely event that you have any coils in an op-amp circuit, you treat them as short circuits, or as the coil's DC resistance only).
In that event, the given expression for \$R_{comp}\$ is correct.


reading in large text files in r

Question: I want to read in a large ido file that had just under 110,000,000 rows and 8 columns. The columns are made up of 2 integer columns and 6 logical columns. The delimiter "|" is used in the file.  I tried using read.big.matrix and it took forever. I also tried dumpDf and it ran out of RAM. I tried ff which I heard was a good package and I am struggling with errors. I would like to do some analysis with this table if I can read it in some way. If anyone has any suggestions that would be great.
Kind Regards,
Lorcan
Comment: Have a look at [this](http://stackoverflow.com/a/1820610/986817).
Comment: Can you provide a sample of the file (the first 5-10 lines)?
Comment: include the code and errors for ff
Answer: Thank you for all your suggestions. I managed to figure out why I couldn't get the error to work. I'll give you all answers and suggestions so no one can make my stupid mistake again.
First of all, the data that was been giving to me contained some errors in it so I was doomed to fail from the start. I was unaware until a colleague came across it in another piece of software. In a column that contained integers there were some letters so that when the read.table.ff package tried to read in the data set it somehow got confused or I don't know. Whatever though I was given another sample of data, 16,000,000 rows and 8 columns with correct entries and it worked perfectly. The code that I ran is as follows and took about 30 seconds to read:
setwd("D:/data test")
library(ff)
ffdf1 <- read.table.ffdf(file = "test.ido", header = TRUE,  sep = "|")

Thank you all for your time and if you have any questions about the answer feel free to ask and I will do my best to help.
Answer: Do you really need all the data for your analysis? Maybe you could aggregate your dataset (say from minute values to daily averages). This aggregation only needs to be done once, and can hopefully be done in chunks. In this way you do need to load all your data into memory at once.
Reading in chunks can be done using scan, the important arguments are skip and n. Alternatively, put your data into a database and extract the chunks in that way. You could even using the functions from the plyr package to run chunks in parallel, see this blog post of mine for an example.

reading in large text files in r


Blender does not utilize full amount of VRAM

Question: When trying to render my scene with my GTX 970 and cycles I get a cuda error saying that I was out of memory. However according to gpu-z I only got up to using 3228MB of VRAM, and according to blender my scene was using a little over 2GB, somewhere in the 2200MB range. Is there a work around, or a know reason for this?
Answer: Unless you have multiple graphics cards you are unlikely to be able to max out the memory use.  Some of the memory will be used by other processes and windows.  I've found it is always worth closing all other windows and any other unnecessary processes when I'm close to the limit.  They all use RAM which could affect your render but they all will likely have staked a claim on some VRAM too.  I don't know whether minimising the Blender program windows makes any difference but I do it anyway.  If you are on Windows I've also found that switching themes can help.  Current Windows versions and their UI effects are not a particularly efficient users of VRAM so dropping back to the Classic theme will probably help.  I've also read that changing font size to normal and switching off clear type and anti-aliasing can help although I've no evidence to support that.
Comment: I've forced every app using my discrete GPU to use the iGPU, including Windows system apps.  My GPU now shows 25% VRAM is free (before there was only ~3% free), yet Blender still refuses to use it.  I even shut down the Blender UI and rendered from the command line with all UI apps shut down, same thing: 25% unused VRAM.  Blender will even swap out whatever it is using to system RAM and pull in more to the VRAM, killing my render time (12 hours vs 18 minutes).  The whole time there is 20%-25% VRAM sitting idle according to Task Manager, Open Hardware Monitor, and AIDA64.  No way around it.
Comment: I think Windows may keep some in reserve, because if I open an app that can use the extra VRAM, the usage will spike to 95-97% while the app is open.  Maybe Linux can allow full VRAM usage for a single app...


why uboot used arm-linux-gcc for default arm CROSS_COMPILE?

Question: i am very strange about the toolchains, arm-eabi-gcc, arm-linux-gcc, and arm-elf-gcc.
For arm-linux-gcc and arm-elf-gcc, in my opinion, just used the different the libc.
But what's the difference between arm-eabi-gcc and arm-linux-gcc ?
i regard that arm-eabi-gcc dont built in the libc. Am i right ?
if not, could you help to correct me ?
And also why uboot used arm-linux-gcc for the default arm cross compiler ?
As i know, the uboot dont need that libc for dependency.
so that is my problem.
thx!
Comment: This answer may also shed some light http://stackoverflow.com/questions/13143393/distro-provided-cross-compiler-vs-custom-built-gcc/13147962#13147962
Answer: It's called the target alias or the target-triplet of the toolchain what it's for, basically, is to identify that toolchain from other toolchains and from the native one you have. It tells you what architecture, ABI and target host the toolchain is built for, example:

arm-none-gnueabi: bare metal (no operating system) gnu ABI
arm-linux-eabi: produces binaries for a hosted system (running a Linux environment)
Answer: The GCC compiler *gcc is a driver program running other programs. So run
arm-linux-gcc -v -O -Wall helloworld.c -o hellworld-linux-gcc
arm-elf-gcc -v -O -Wall helloworld.c -o hellworld-elf-gcc
arm-eabi-gcc  -v -O -Wall helloworld.c -o helloworld-eabi-gcc

and you'll understand the differences. They probably all run some cc1 program doing the translation to assembly code, some as program doing the assembling of assembler code to object code, some ld program doing the linking with some standard libraries. They may also run some collect2 wrapping some linking etc etc.
You may also want to run simply arm-linux-gcc -v or arm-elf-gcc -v or arm-eabi-gcc  -v to understand how your compilers have been configured, and their precise version.

why uboot used arm-linux-gcc for default arm CROSS_COMPILE？


How to stop Play Store from auto-updating itself?

Question: How can I stop Google play from automatically updating to the latest version? I tried deleting my hosts file but it's not being deleted. My phone is rooted.
Comment: @xavier_fakerat if Play Store is installed as user app or is updated at least once, try making its `apk` file immutable. If `installd` fails deleting existing file/directory, may be new one is not created. Or replace its privileged `android.permission.INSTALL_PACKAGES` with `REQUEST_INSTALL_PACKAGES` (though doesn't make much sense). Or disable `SafeSelfUpdateService` and `EmergencySelfUpdateService` components of Play Store app (though app it self can enable them any time). Never tried any of these. Also may cause app crash.
Comment: I tested disabling those 2 services through Apps2SD's App component manager, clicked on Update Play Store inside Play Store settings, and they remained disabled (Play Store didn't updatae).
Comment: Never mind, it did update the next day (and the services are still disabled according to Apps2SD).
Answer: In order to disable Google Play Store:

You must have version 4.8.2 installed (just replace it in /system/app with the new com.android.vending.apk).
Download a root service from the store called Disable service (again make sure root is installed and the app is given root permission).
Now, in the disable service app, navigate to the system app tab and find Google Play Store. Tap on it and you will get a list of services.
Scroll to the bottom and uncheck Check Wi-Fi and Update service.
You will see a Please wait notification, and at the bottom BusyBox should appear, notifying you that the app was given root access.
Exit the app and voila! Google Play Store will never update itself or Google Play Services ever again (unless you install a new version, in which case you would need to repeat the process).
Comment: Where can I find version 4.8.2?
Answer: First, you must have version 4.8.2 installed (just replace it in /system/app with the new com.android.vending.apk).
Instructions (from here):

Root, install SuperSU.

Install BusyBox, then terminal emulator.

Stop any Internet access on your Android, or it will silently auto-update Store, making your hard typing work useless.

Open Settings -> App manager and find Play Store. tap on it. It will open the properties window. There will be button Uninstall Updates. Tap on it, click Yes on Replace with factory version? question.

Because there is no Internet connection, this is the moment the Play Store couldn't be updated. Let's use it.

Open terminal emulator and type commands one by one:
su

(at this time SuperSU app will ask you for granting root access for terminal emulator app, click Grant access).
touch /data/app/com.android.vending-1.apk
chattr +i /data/app/com.android.vending-1.apk

Enjoy! Regardless of Internet connection, Play Store now has the version you need, not Google. This might work for Play Store 4.8 and up, but I didn't test it.
Comment: This will not solve the problem, because it will keep downloading the whole thing into a temp folder again and again and again...
Comment: +1 The answer that **actually works**. Note that you may have to replace `-1` with `-2` if that already exists. (But don't go to `-3`!)
Comment: Comments are not for extended discussion; this conversation has been [moved to chat](https://chat.stackexchange.com/rooms/133474/discussion-on-answer-by-alex666-how-to-stop-play-store-from-auto-updating-itself).
Answer: A modified version of Stephen Schrauger's steps, based on the video here, since chmod +i returned an error on my phone. Tested on Android ICS (Cyanogenmod 9, Play Store 3.*).
Assuming a rooted phone:

Stop whatever Internet access on your Android or it will silently auto-update Play Store, making your hard typing work useless.
Open Settings → App manager and find Play Store. Tap on it. Tt will open properties window.
There will be button Uninstall Updates. Tap on it, click yes on "replace with factory version?" question.

Because there is no Internet connection, this is the moment the Play Store can't be updated. Let's use it.
Open Terminal Emulator and type the commands one by one:
su

At this time supersu app will ask you for granting root access for Terminal Emulator app, click grant access.
mkdir /data/app/com.android.vending-1.apk

Instead of creating a file and preventing modification with permissions it just creates a directory, which can't be overwritten by the updater.
Now you can re-enable the internet connection and it will not update unless the directory is deleted.
Answer: The ultimate guide to stop Play Store auto-updates on Android 10 & Lucky Patcher. My device: Xiaomi S2, Android 10, EU ported MIUI 12.0.8.
This guide assumes you have a custom recovery & Magisk installed. If not, then do it first. We're gonna go in 4 step process:

SELinux permissive:
First, go to Magisk manager & flash SELinux module. Follow the flashing instructions & set SELinux to permissive.

Uninstall the original Play Store:
Go to /data/app/com.android.vending folder (your device might have some random string name, so find the folder where Play Store is. It might be under the name base.apk/vending.apk/market.apk/playstore.apk), delete the folder using SD Maid app.
[Note: I tried a bunch of other file managers like FX File Manager, Xplorer, Root Browser, but for some reason they did not work.]

Delete the basic version of the Play Store from the system that automatically reinstalls: Using SD Maid, go to system/product/priv-app/Phonesky. This is the basic version, delete it.
[Note: If for some reason you are having trouble with steps 2 & 3, then go to your custom recovery mount system partition & follow these steps from the custom recovery.]

Now if you have a modded APK from Lucky Patcher, then place it in the Phonesky folder. If not, then install the modded Play Store from Lucky Patcher app. Take a backup of the modded Play Store using any backup app. Then place it in the Phonesky folder.
Go to app manager from settings to see if it has been installed as a system app. If you can uninstall from settings, then do it. It will automatically reinstall the modded version.
[Note: If Play Store still auto-updates, then repeat the process & then set the permission of Phonesky folder to r--r--r (444)

Flash SELinux Magisk module & set SELinux to Enforcing.

Play Store will never auto-update itself again & Lucky Patcher will start working on Android 10. This trick can also be extended to Android 9 & 11.
Answer: Some android apps depend on PlayStore and GooglePlayServices and therefore I would not advise to disable them. However, if the phone has ROOT (SuperSU or Magisk), it would be possible to mount system partition as Read/Write and modify the file /system/etc/hosts:
127.0.0.1 localhost
0.0.0.0 android.clients.google.com
0.0.0.0 android.googleapis.com
0.0.0.0 app-measurement.com
0.0.0.0 connectivitycheck.gstatic.com
0.0.0.0 dl.google.com
0.0.0.0 firebaseinstallations.googleapis.com
0.0.0.0 pagead2.googlesyndication.com
0.0.0.0 play.googleapis.com
0.0.0.0 play-fe.googleapis.com
0.0.0.0 play-lh.googleusercontent.com
0.0.0.0 r15---sn-n8v7kn7r.gvt1.com
0.0.0.0 r2---sn-n8v7knee.gvt1.com
0.0.0.0 r2---sn-n8v7znz7.gvt1.com
0.0.0.0 www.googleapis.com

This modification would prevent PlayStore from updating.
Comment: I can't say for sure. I can only guess which lines are responsible for Play Store update. E.g  the GVT in the gvt1.com domain stands for Google Video Transcoding, and is used as a cache server for content and downloads used by Google services and applications. *.googleapis.com is related to Google APIs and responsible for authentication. *.googleusercontent.com is some kind of cache. pagead2.googlesyndication.com is AdSense and may not be related to Play Store update.
Comment: app-measurement.com is responsible for collecting statistics from android apps. connectivitycheck.gstatic.com is a beacon used to check if android phone is on wifi or not. The remaining lines android.clients.google.com and dl.google.com may be responsible for blocking Play Store and Play Services updates.
Comment: So which of these lines are actually responsible for blocking a Play Store update? It would be nice to post only related lines. Will this also block an update of Play Services?
Answer: In the system folder there should be MarketUpdater.apk. If you delete that file, Play Store won't update itself anymore. Nothing else should be affected though.
Comment: I couldn't find that file, I think they've discontinued it some time ago.
Answer: I found another approach to Google Play Store based on its dependency on built-in Download provider:
chmod 551 /data/data/com.android.providers.downloads/cache
chmod 551 /data/data/com.android.providers.downloads/files

make it impossible to update both Store and other programs (including Google Play Services) in my Lolipop 5.0.1. When I need to update third-party programs, I run Store, then file manager (I use X-plore), change permissions of folders back to 771, install found updates, return to file manager and set permissions to 551 again, at the end I close the Store. Quite simple and very reliable - no background updates of the Store and Services for two months.


Microsoft.Speech.Synthesis - Chinese speak error (zh-CN, HuiHui)

Question:
It seems like the Microsoft Speech Synthesis issue with Chinese (HuiHui) is still running into the wild.
After some researches online and few tries to fix it I couldn't find any solution.

The setup
Windows 10 (x32) (tested on x64 too)
SDK 11
Visual Studio 2017

The error
InnerException = {"Catastrophic failure (Exception from HRESULT: 0x8000FFFF (E_UNEXPECTED))"}
Message = "Speak error '8000FFFF'."
Source = "Microsoft.Speech"

The troublesome code
using Microsoft.Speech.Synthesis;

using (var ss = new SpeechSynthesizer())
{
  ss.SetOutputToWaveFile("output.wav");
  ss.SelectVoice("Microsoft Server Speech Text to Speech Voice (zh-CN, HuiHui)");
  ss.Speak("我喜欢和很多珍珠奶茶"); // speak error here
}

This code is working perfectly using English (en-US, Helen).

Failed fix attempt
Download "chsbrkr.dll" & "chtbrkr.dll"
Add it to "Program Files((x86))\Common Files\Microsoft Shared\Speech\TTS\v11.0"

Does someone has succeeded in running this script in some way or has found an alternative ?

Thank you.

Previously posted on the same topic
Chinese TTS fails, while English works

TTS for Chinese is throwing SAPI ERROR E_FAIL

ASP.Net and Microsoft.Speech error with Chinese
Answer: Try registering these two dlls "chsbrkr.dll" & "chtbrkr.dll".
Try the below steps and check -
1) Paste the two dlls in "C:\Windows\System32" directory. If you are using a 64 Bit operating system, paste the two dlls into the "C:\Windows\sysWOW64" as well (copying requires administrator previlage).
2) Register the two dlls in the system using the below commands in command prompt(Run as Administrator)

%windir%\System32\regsvr32.exe /u Chsbrkr.dll
%windir%\SysWoW64\regsvr32.exe /u Chsbrkr.dll
%windir%\System32\regsvr32.exe /i Chsbrkr.dll(you may see error at this step,can ignore)
%windir%\SysWoW64\regsvr32.exe /i Chsbrkr.dll(you may see error at this step,can ignore)
%windir%\System32\regsvr32.exe /u Chtbrkr.dll
%windir%\SysWoW64\regsvr32.exe /u Chtbrkr.dll
%windir%\System32\regsvr32.exe /i Chtbrkr.dll(you may see error at this step,can ignore)
%windir%\SysWoW64\regsvr32.exe /i Chtbrkr.dll(you may see error at this step,can ignore)

After doing this try restarting the system and then try running the application where you were seeing the "Speak error".
Hope this resolves the issue.
Answer: Hello a similar error appears when you work with excel 2013 and try to make a macro in visual basic
I am trying the next code:
Sub Main()
Dim speech As New SpVoice
Dim i As Long
Dim oFileStream As New SpFileStream
Const SAFT48kHz16BitStereo = 30
Const SSFMCreateForWrite = 3

For i = 1 To 5
Set speech.Voice = speech.GetVoices.Item(3)
speech.Speak (Cells(i, 6))
Application.Wait (Now() + TimeValue("00:00:02"))

Next i
End sub
error seen
table of words


How do you use a Log-linear model when you have negative Xs?

Question: I am trying to us a Log-linear model to derive an elasticity. However, some of my Xs are negative numbers. Being as the model relies on the natural log of the Ys and the Xs, how can this model work when the natural log can only be taken of X>0?
Comment: There are a few tricks. A good one is to transform the variable to a positive only number. If your variable is a net value, maybe a gross value would be more appropriate. Can you be more specific?
Comment: Sure thing: my Xs are observations of liquidity gaps, most of which tend to be in surplus, but some of which are also deficits (hence the negative numbers). I thought about what you said and considered perhaps taking the absolute values of all the numbers but I'm not confident that this is the right way to find a meaningful elasticity.  I am also wondering how legitimate of a workaround adding some constant to all the Xs (and the Ys?) would be?
Comment: (p.s. I also realize you were't suggesting using absolute values -- this was just my first impulse to get around negative numbers)
Comment: Adding some arbitrary constant is usually not recommended, unfortunately. I'm just thinking here... If you have a gap, that's a gap between two positive numbers. what about the log difference between the two. If your gap is defined as a-b, why not try log(a)-log(b). Might give you something meaningful.
Answer: The elasticity of Y with respect to X is often estimated by running a regression like this:
$$ \ln Y = \alpha + \beta \ln X + error$$
However, this isn't always applicable because it is perfectly fine to ask what is the percent change in Y to a percent change in X even if X or Y are negative. There are other issues too, like the fact that the elasticity may not be constant over X.
Let's go back to the textbook (Varian (1992), p. 235) for the definition of the elasticity of $Y$ with respect to $X$:
$$ \epsilon(Y,X) =\frac{\partial Y}{\partial X} \cdot \frac{X}{Y} $$
Which equals another common definition of the elasticity:
$$=\frac{\partial \ln Y}{\partial \ln X}$$
which we often use when estimating the elasticity with linear regressions.
However, the advantage of the first form is that you don't have to use the log function to evaluate it. All you need is a local estimate of the derivative, X, and Y.
One strategy would be just to do that.
However, what you are doing could well be nonsensical because percentage changes are weird when working with negative values. For example, consider X going from -11 to -10. This is a 9.1 percent decrease in X ((-10-11)/-11). However, this is is an increase in X! Going from 11 to 10 is also a 9.1 percent decrease in X. What would be the economic conditions where we think going from -11 to -10 and +11 to +10 would have the same effect on demand?


Is the word problem for regular languages in ALogTime?

Question: Given a regular language (by a sparse or dense matrix describing the graph of the NFA) (initially the description was supposed to be a regular expression) and a word, can the problem whether the word belongs to the regular language be decided on a (random access) alternating Turing machine in a logarithmic amount of computation time? (The many links above try to compensate for the fact that I didn't find a nice self-contained description of ALogTime.) The length of the input is the length of the description of the regular language plus the length of the word.
Answer: If the regular expression is not fixed, it is rather doubtful that your problem belongs to ALOGTIME. However, the phrase word problem usually refers to a fixed setting, which in this case means that the regular language is fixed.
If the regular language is fixed, this is apparently shown in Barrington's famous paper. Alternatively, you can describe a logtime game for deciding the word problem for regular languages. The game starts with the YES player stating the final (accepting) state and the state at the middle (the initial state is of course fixed). The NO player then chooses one of the halves, and the game continues until it comes down to a word of length 1, in which case the problem can be settled by examining one character of the input.
Comment: If I would include the (sparse or dense matrix describing the graph of the) NFA instead of the regular expression, then it seems that checking the last step (in NLogTime) would be possible. Do you agree? (I only wrote regular expression instead of regular language, because it seemed more convenient and explicit. I didn't intent this to have any impact on the actual answer to the question.)
Comment: Yes, this sounds reasonable.
Comment: If the NFA (or regular expression) is not fixed, then the size of a state is $\log n$. Even so the algorithm above will still work perfectly well, it will take more than $\log n$ time. Which is a good thing, since the NFA membership problem is NL-complete. (I added a community wiki answer below, which explains why this observation is nearly trivial.)
Answer: If (the regular expression or) NFA is not fixed, then the problem is NL-complete. So if the problem would be in ALogTime, then ALogTime=L=NL, which is an open problem.
It is clear that the problem is in NL, we only need one pointer into the word on which the NFA runs, the current (and guessed next) state of the NFA (its size is $\log |A|$, if $A$ is a description of the NFA by a list of possible transitions), and a pointer into the description of the NFA.
To see that it is NL complete, reduce reachability to the NFA membership problem over the unary language. Use the given digraph as NFA, and add a self-loop to the target node whose reachability is being checked. Let the source node be only state in the set of initial states, the target node be the only state in the set of (accepting) final states, and check whether this NFA accepts the word $1^n$, where $n$ is the number of nodes of the given digraph (which is also the number of states of the constructed NFA).
The reason why Yuval Filmus' algorithm (explained in his answer above, together with the comments below) doesn't solve this problem in ALogTime is not that the last step would not work. That checking can indeed be done in NLogTime. But the size of a state is $\log n$ if the NFA is not fixed, and hence the algorithm takes $\log^2 n$ time instead of $\log n$ time.