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00:03
2
Q: Should I work for free if client's requirement changed

VarunAgwI have a client. There was one specific limitation of the solution we were implementing. I made sure to tell him about it, and he said it's fine. Now later when it's implemented that way, he feels, it's not ideal for him. Overcoming this limitation would require redesigning the current work, and...

posted on July 20, 2019

From Pᴀᴜʟsᴛᴇʀ2 and tagged as print-orientation

00:34
1
Q: Is it possible to have mutliple concurrent coprocesses?

kjoThe intent of the test script1 below is to start an "outer" coprocess (running seq 3), read from this coprocess in a while-loop, and for each line read, print a line identifying the current iteration of the outer loop, start an "inner" coprocess (also running seq, with new arguments), read from t...

2
Q: Differentiability and limits

JanSuppose one is asked to explain why the real valued function $$f(x) = \sqrt[3]{x}$$ is not differentiable at $x = 0$ and gives the following argument: For $x \neq 0$, one has $$f'(x) = \frac{1}{3\sqrt[3]{x^2}}$$ and this is not defined for $x = 0$. Is this a perfectly valid argument? In my op...

01:15
4
Q: Counting multiples of 3 up to a given number

therealshankmanI'm attempting a practice problem in Codeforces that requires you to find the number of multiples of 3 less than or equal to a given number. I have written the following code but it gives a TLE once the test case reaches the order of 108. int x = Reader.nextInt(); int count = 0; for(int i = 3; i<...

01:31
9
Q: What's the physical meaning of the statement that "photons don't have positions"?

knzhouIt's been mentioned elsewhere on this site that one cannot define a position operator for the one-photon sector of the quantized electromagnetic field, if one requires the position operator have certain formal properties. This is a theorem that holds only for massless particles of helicity $|\lam...

3
Q: orthogonality of complex exponentials

karagedonI want to show that $(1+e^{-j2/3 \pi}+e^{-j4/3 \pi}) = 0$. The property that I am supposed to use is that of orthogonality of complex exponentials. This means that if $e^{-j(2\pi kn)/N }$ will be equal to N when $n=lN$. My problems are that the rule is applied when its a sum and this case its...

01:58
4
Q: Label distance number and chromatic number of a graph

Dominic van der ZypenLet $n\in\mathbb{N}$ be a positive integer, and let $[n] = \{1,\ldots,n\}$. We set $S_n$ for the set of all bijections $\varphi:[n]\to [n]$. Let $G= ([n], E)$ be a simple, undirected graph, and let $\varphi\in S_n$ We define the label distance number of $G$ in the following way: $$\lambda(G) = ...

IOT
IOT
2
Q: Zigbee and supporting devices - UK

RickyI'm reasonably new into the smart home stuff and IoT's, but after some research I look to use something like HomeAssistant or OpenHAB. From what I'm reading you need bridges for specific devices, unless they support Z-Wave or Zigbee (may well be wrong on this...). So, being a coder I like open ...

1
Q: Get Chord Name From a Given Set of Notes

Cheche RomoI am trying to come up with an algorithm that gets the proper chord name given certain Notes, user may or may not inform which from the notes is the root. I suppose that the process in recognizing a chord name differs for how many notes are given, so maybe there should be an algorithm for triads...

02:24
10
Q: 70s Sci-Fi Story including/describing Conway's solitaire game "life"

NJohnnyEarly 70s Sci-Fi book, I believe it was 2 humans (man and woman) on an alien planet... (I don't think they were stranded, I think they were there to explore.) There may have been a few more people with them. But I mostly recall just the two. I believe the man was doing something and to keep the ...

TeX
TeX
1
Q: Deleting a point in METAFONT

ToothrotIn METAFONT, run interactively, is it possible to give a new value to a point variable? If you just try to equate a point to a new point, the equation will be inconsistent with other equations. If you try to assign a new value, MF says that := is ''improper''. And you can't wipe out z5 by pair...

3
Q: Formating slide

Murilo Araujo Souzai need help formatting this slide: As you can see, the text above the first table isnt in the same line as the text above the second table. How can i put them in the same line? Heres the code that generated it: \documentclass[aspectratio=169]{beamer} \usetheme{Warsaw} \setbeamertemplate{headl...

02:41
5
Q: Term for future-tense technique that isn't exactly foreshadowing

purpleladydragonsNot sure if this has a name, but I think it's best demonstrated with some examples I've seen: Nadia and her family both considered her thereafter to be without a family, something all of them, all four, for the rest of their lives, regretted, but which none of them would ever act to repair [....

03:22
2
Q: What does "mossette" translate to in English

MemmingWhat does "mossette" mean? It's not listed in the dictionaries I looked up. I'm guessing there's no appropriate English translation? Example sentences: tra mossette e gridolini fissa gli spettatori con stupore. I primi gridolini, certe mossette piene di grazia di Ninnì lo facevano impazzire da...

3
Q: Do Indians need sepearte Hong Kong visa if we already have Chinese visa

Raja GopalDear fellow traveller's I have a query. I have got single entry Chinese visa from India. Now I planned to add Hong Kong to my trip plan. Whether I need sepearte visa to be got for Hong kong or with Chinese visa can I travel to Hong Kong. If I need sepearte then is visa on arrival possible for Ind...

4
Q: Found old paper shares of Motorola Inc that has since been broken up

thelegend27I found 36 physical shares of motorola inc from 1999. I know that since then the company has split up into a lot of subsidiaries/mergers. Is there any to sell this physical stock or is it worthless? if not worthless, do you have any idea what the value is?

RPG
RPG
03:53
4
Q: Does the Bracer of Flying Daggers really let a thief make 4 attacks per round?

the dark wandererThe Bracer of Flying Daggers (from Waterdeep: Dragon Heist) lets you use an action to activate the item to make two normal thrown dagger attacks. There's no limit to the number of times the item can be activated, though it does require attunement. A thief can, at 3rd level, use their Cunning Ac...

2
Q: Why there is no article before venture capital firm in "Beller’s first high-profile role was at venture capital firm Andreessen Horwitz, .."?

Jerzy BrzóskaBeller’s first high-profile role was at venture capital firm Andreessen Horwitz, where she was a partner on the deal team between 2013 and 2016. Source Does the same rule apply to the sentence above as to the expressions like at work, in hospital, and at school? Is Beller’s first high-profile ro...

1
Q: Can a creature sustain itself by eating its own severed body parts?

Li JunI was inspired by geckos which can sever their own tails. I wonder if a creature which has such an ability, especially with a high regenerative power to grow its body parts, can sustain itself over and over by only eating its own body parts, rather than as distraction like geckos do. It may not...

04:11
2
Q: Did I pick the wrong bike?

Loren StevensonI live 7.2 miles from where I work and was rebuilding my life, so no car. I was walking to work everyday until my son took me to Wal-Mart and said I was getting a bike. I picked out a Kent 26 Bayside 7-speed cruiser. I am 5ft 9in tall, 225 lbs and generally a big stocky guy. Aside from taking...

DIY
DIY
3
Q: Replacing light switches and outlets without electrical boxes

TannerI have a '96 manufactured home I'm getting ready to sell and most of the outlets and switches are a tan color that doesn't work with the color scheme I'm changing it too, plus they just look dirty. I just pulled the first switch out to find they used a switch that has little plastic feet to hold ...

3
Q: Why do we need an estimator to be consistent?

FamI already understood the mathematical definition of a consistent estimator. Correct me if I'm wrong: $W_n$ is an consistent estimator for $\theta$ if $\forall \epsilon<0$ $$\lim_{n\to\infty} P(|W_n - \theta|> \epsilon) = 0, \quad \forall\theta \in \Theta$$ Where, $\Theta$ is the Parametric Sp...

04:54
2
Q: Doesn't the Schrödinger's cat inside the box cause the probability wave function to collapse long before a human opens the box?

Eddie BravoMy point is that there is no superposition of dead and alive. The cat will cause the probability function to collapse long before we open the box. What am I missing here? Isn't the cat capable of collapsing the probability function? If not, why?

4
Q: How far off did Apollo 11 land?

DarkDustArmstrong wasn't able to land exactly in the designated landing location, as far as I know it was too rocky. So he had to fly a bit farther to find a suitable spot. But how much farther from the designated location did he land? A few hundred meters? A few kilometers?

05:15
1
Q: Is this guy trying to scam me?

NicholeI met a guy online and we FaceTimed and used Skype to make sure that we both were the people in the pictures. He’s from Estonia but lives in Alabama. He had to go home because his mom passed away but he says he wants to move to my home town when he comes back. He asked me to go look at a $500,000...

3
Q: Why xargs uses -t to enable verbose mode?

jiwopeneMost programs use -v to enable verbose mode. Why does the GNU xargs use -t to enable verbosity?

RPG
RPG
05:35
8
Q: Do gauntlets count as armor?

user3731568Do gauntlets count as armor? Specifically, would wearing Gauntlets of Ogre Power negate the AC bonus that barbarians and monks get because they are technically armor? I feel like they wouldn't.

3
Q: Is there a standard frequency for wandering monster checks in a dungeon?

munkIs there a standard or default frequency for wandering monster checks in an underground dungeon? This concerns both dungeons of my own design, and existing modules either by TSR or Judges Guild that do not specify an encounter frequency for the dungeon.

2
Q: Consequences of stalling while sideslipping in a glider?

Stefano BoriniIn a glider, sometimes it's useful to do a side slip with crossed controls. However, when that happens, the pitot tube angle is out of line and the ASI goes to zero, therefore losing any indication of the current airspeed until the sideslip is interrupted. During this maneuver, what would happe...

TeX
TeX
3
Q: Table Formatting Suggestion

Aiden KennyThis is more of an open-ended, personal opinion type question. I am trying to make a nice-looking table for a report. Here is what I have so far: The contents of each are slightly different, but the formats are identical: 8 rows and 10 columns. The first column explains some of the variables b...

06:01
4
Q: Is it ethical to tell my teaching assistant that I like them?

apollogieI, a 20-year-old female, have come to admire the teaching assistant for my summer course quite strongly. I'm extremely interested in what they have to say, I always pay attention, never use my phone and use eye contact to show interest (i do come 2-5 minutes late sometimes but that's because i c...

1
Q: Out of disk space, no Gparted no update

SmileynatorI seem to have worked myself into a perpetual problem. My Ubuntu version is outdated, and even with some fixes, trying to install Gparted seems impossible (first couldn't find it, now it can but somehow still doesn't install) (looks like this issue: "Unable to locate package" while trying to ins...

06:19
2
Q: Satellite in orbit in front of and behind the Moon

BingohankWould it be possible to put a satellite into the same orbit as the Moon, but far enough ahead or behind the Moon to remain in place? Has this ever been done in practice?

2
Q: Options for making rocket fuel using the Moon's natural resources

Bob BaileyBased on what is known about the chemistry of the lunar surface through remote sensing and surface exploration, what raw ingredients are likely to be available that can be used to make rocket fuel?

3
Q: How does the Gameboy's memory bank switching work?

David TranI'm writing a Game Boy emulator, but I don't completely understand how its memory mapping works. Here is what I (think) I know (and don't know). The CPU can address up to 0x10000 memory locations with the 16-bit address bus. The memory is mapped as follows: $0000-$3fff: a 16KB ROM bank. Initial...

06:34
2
Q: Contaminated Ground vs. Blink of an Eye

Robbie GiffordI have a tough ruling I need some help with: On my opponent's turn he played Contaminated Ground on my Island. I tapped that Island for blue mana in response. I then wanted to let the stack resolve and cast Blink of an Eye on Contaminated Ground before the end of the step. Rule 500.2 is what make...

06:49
1
Q: Derivative of Sort

stivI want to calculate gradient of Sort[{x1,x2,x3,x4}] but it seems like I'm getting a wrong answer. Specifically Plot[Sort[{2, 1, x, 10}][[4]], {x, -20, 20}] gives me while D[Sort[{2,1,x,10}],x] returns {0,0,0,1}, which is not true. Is there a way to fix it?

07:05
3
Q: Host telling me to cancel my booking in exchange for a discount?

the manI booked through booking.com about 2 months ago, made a prepayment and everything. The place I booked has free cancellation up until 2 weeks prior. Now, the host has e-mailed me offering me a discount on the payment if I cancel the booking? The host says that the booking will still be mine and ...

4
Q: Aren't all schwa sounds literally /ø/?

VictoriaAs I have described on the title, I find that /ə/sound doesn't exist in Parisian accent. When I asked how to pronounce Monsieur to a French native speaker, he tried very hard to correct my IPA pronunciation /məsjø/. It was as if he wanted me to pronounce it as /møsjø/. If this is the case, how ...

07:34
2
Q: "Buddha does not claim to be a creator of lives or the Universe.", true?

Samana JohannVen. and good Buddha-Parisatas, A statement from a commercial Website here says: "Buddha does not claim to be a creator of lives or the Universe." Is that right, or wrong and how to understand such right? (Note that this is not asked for trade, exchange, stacks, entertainment and akusala deed...

07:59
2
Q: How much did all the space agencies spent on rockets launching and space exploration? What are the benefits for me and you?

Ashraf MohdI thought about how much does one rocket cost to build and launch and it came up with roughly $500 million including everything. That made me pause and wonder for myself what it is that's out there that might be worth this money, and reflect upon the many problems on Earth that could be addresse...

CS
CS
08:34
1
Q: One-way Trapdoor Function

Lance WeingartzDo the functions of the collatz conjecture and their inverses model a Trapdoor Function? That is, given f(n) = n/2 or 3n+1 and the inverse g(n)=2n and (n-1)/3 it is easy to go from 42 to 1 by repeating the steps but it requires a nondeterministic Turing machine to find g(42).

09:00
1
Q: Is there a characterization of the cuspidal automorphic representations that arise from elliptic curves?

Grad studentIs there a way to characterize (e.g. by their local components) the cuspidal automorphic representations that arise from elliptic curves? There is a procedure to go from elliptic curves to cuspidal automorphic representations of $GL_2$ but can the image be characterized?

2
Q: Ethiopian Airlines tickets seem to always have the same price regardless of the proximity of the date?

xjiI am planning a trip to Ethiopia. It seems that to travel between Ethiopian cities, the easiest way is to take flights operated by Ethiopian Airlines. Normally for trips in Europe/America etc., you would book flight tickets well in advance in order to have the best prices. However, on the offic...

09:21
3
Q: Why does Sherlock (BBC) use miles?

BrettFromLAI've just started watching the BBC series Sherlock on Netflix. In the first 5 episodes, we've noticed that Sherlock and Watson always refer to long distances in miles rather than kilometers. It was my understanding that, since they are in the U.K., distances would be measured in kilometers. Is th...

 
1 hour later…
10:36
5
Q: Variance vs standard deviation

tinIf I wanted to measure a fantasy MLB player’s potential to outscore his average on a given night would variance or standard deviation be a better indicator?

10:46
4
Q: Detention in The Forbidden Forest

Jordan CarreiraWhy would detention take place in The Forbidden Forest? Besides walking around at night, what was their assignment? I wouldn’t expect for them to be doing something useful especially during the night, so I don’t get the point of them having detention set in that place.

11:04
7
Q: How to extract array from JSON object

stackmj18How to extract only the array from a multi-level JSON object. {'students': {'student':[{'name':'john','age':30},{'name':'peter','age':25}]}} I want to extract only: [{'name':'john','age':30},{'name':'peter','age':25}]

11:25
6
Q: Why didn't Balak request Bilam to bless his own people?

DanFWhen Balak summons Bilam, he says, "For I know that whomever you bless will be blessed and whomever you curse shall be cursed." This implies that Balak understood that Bilam's main strength was in blessing people, and the secondary strength was in cursing. If that's the case, and he feared the I...

3
Q: Order of compound particles

Right legI came across the following sentence: 彼氏と大喧嘩して、お前とはもう別れたいとまで言われた。 Why are と and まで in that order? Would "別れたいまでと言われた" be incorrect? Is there a rule concerning the order in which particles must be assembled?

11:46
2
Q: Old book about a young man marooned in space who is drawn to an alien shipwreck by a ring he is wearing

twistIt was a school library book I read in the 70s, about a young man marooned in space who is drawn to an alien shipwreck by a ring he is wearing. Can't seem to remember more, but the image has stayed with me...

12:05
5
Q: Is a woman considered a sotah if she cheated on her husband with another woman?

Benzion KlatzkoWould a woman that cheated on her husband with another woman qualify as a sotah? יז: וְלָקַח הַכֹּהֵן מַיִם קְדֹשִׁים, בִּכְלִי-חָרֶשׂ; וּמִן-הֶעָפָר, אֲשֶׁר יִהְיֶה בְּקַרְקַע הַמִּשְׁכָּן, יִקַּח הַכֹּהֵן, וְנָתַן אֶל-הַמָּיִם 17: The kohen shall take holy water in an earthen vessel, and some...

12:35
2
Q: Why is there an extra "t" in Lemmatization?

asmgxWhen we say : Specify, it becomes Specification (no t) Value, it becomes Valuation (no t) Custom, it becomes Customization (no t) Lemma is a code used in programming, to describe the process of doing this Lemma, the word used is "Lemmatization". I wonder where did the "t" in Lem...

12:57
2
Q: BIP-23 criticism: Is bitcoin PoW actually sha256+merkleGeneration? Or have I misunderstood coinbase/append?

ascendzorI'm new to the low-level protocol stuff. Here is my understanding of the scenario, which might be incorrect and hopefully will be corrected: Miners can mutate nonce (32bit) + time (mutates once a second). This allows for 232 (~4million) hashes per second. That's not enough anymore for our ASICs ...

13:13
1
Q: why neutral does not shock. how can a neutral be neutral in ac current?

JyotirWhen I probe my city mains with one probe in the live and one in earth (which should be 0 volt) it shows a voltage of around 250v. But when I probe the neutral and the earth it shows no voltage. I know that current runs in one direction for 50 times in a second. So the neutral should act like liv...

14:06
5
Q: What does Windows' "Tuning up Application Start" do?

AybeWhen installing an old version of Windows, there is a step about application start tuning: This is not about the PREFETCH folder, since this feature appeared in Windows XP. Question: Does anyone know what Windows performs during this step?

3
Q: How is it possible for the induced emf to take negative values in Faraday's Law of induction?

Contravariance Faraday's Law of induction states that the work done per unit charge by the (induced) electric force along a loop of wire, or the emf, is minus the rate of change of magnetic flux through the loop/surface and is given by the equation $$\mathcal{E}_{Ind.}=\oint \vec E_{Ind.}d\vec l=-\frac{d\P...

14:26
3
Q: What is tar -xvf

SamathaI am learning about the basics of Linux and archiving/compressing TAR files i have stumbled across tar -xvf and was wondering what it does i have checked the man pages and know that x means extract and v means verbose but what does f do?

4
Q: Are there theorems about extraneous solutions?

JaullAre there theorems about extraneous solutions? What causes them and how many are produced? If so, which branch of mathematics would I find such theorems (and proofs)? Same thing with missing solutions.

15:24
4
Q: ESTA Travel not Authorized. Accepted twice before!

Maria MartinezHope someone can give me some advice. On Friday I applied for the ESTA (a group application including my partner) we both were not authorized to travel. He just got his new passport on Thursday July 18 and I have my old one from 2016 still valid until 2021. We have gone twice to the US and in bot...

ELL
ELL
15:50
1
Q: What does "play in traffic" mean?

Peace They’ll go snort an eight ball of cocaine and play in traffic... I didn't find any meaning in reliable online dictionaries. Is this synonymous with go play in traffic? To go away and leave one alone because what is being done or said is very irritating. Could you help me please? Th...

16:05
7
Q: Time war story - soldier name lengthens as he travels further from the battle front

PaulwThis is a short story I read in the late 80s. A soldier called H leaves an embattled position near a time-rift battlefront where humanity and unidentified aliens are shelling each other to prevent a crossing. He is going on leave to see his family and travels on a series of carriages like train ...

2
Q: What does a Nintendo Game Boy do when turned on without a game cartridge inserted?

Curt J. SampsonWhen a Nintendo Game Boy is turned on, it displays a logo read from the cartridge (looking like this) before starting the game. What does it display if there's no cartridge inserted from which to read the logo? And what happens after that?

16:30
1
Q: TCP connections hang during handshake

rrrrrrrrrrrrrrrrFor the last few days, connections originating behind my LAN's NAT have been having issues completing the TCP handshake (i.e. web pages only load after hitting F5 a few times, network applications sometimes timeout, etc.). After a TCP connection is estabilished, everything works fine. My network...

16:52
1
Q: What is really the difference between uniform velocity and constant velocity?

GOGAI've been studying kinematics just for a while, and the question that bothers me the most is the difference between those two. I think that there is a difference, such as uniform velocity implies constant speed (but does not imply constant direction) and constant velocity implies constant speed ...

1
Q: Optimizing code to use less Flash Memory and SRAM

newbieI'm trying to reduce my sketch size and managed to reduce both SRAM and Flash memory. From: 1570 SRAM - 32144 Flash memory To: 644 SRAM - 19458 Flash memory This are what I've done so far: ✓ Enabling LTO ✓ Using PROGMEM ✓ Dropping string and using char ✓ Dropping bootloader ✓ Using port...

TeX
TeX
17:08
2
Q: Longtable of size \textwidth exceeds right margin

Jörg KrauseI try to create a table with the longtable package that fits into the whole text width available. Here's my code: \documentclass{article} \usepackage{longtable} \usepackage{amsmath} \title{Raccolta delle formule} \author{} \date{} \begin{document} \maketitle \begin{longtable}{p{.33\column...

17:31
2
Q: A Real World Example for Divide and Conquer Method

happyCan someone give a real world example for divide and conquer method? Such as boomerang is for loop back address what is the real world example we can use to teach students about Divide and Conquer method before going to complex algorithms ?

17:45
1
Q: As a noob by mistake i ran "sudo chown $pranav.pranav -R /" to solve my Read Only Filesystem. If this is a bad thing, how should i undo this?

Prabesh BhattaraiHow should i do to undo this? I tried running fsck to solve my "Read only filesystem" before but it didn't help me much. It only solve the situation for a while and then it comes back again. So, i did this after reading a post. Meanwhile, i am getting thousands of lines like this: chown: changi...

17:59
1
Q: Nilpotent elements of Lie algebra and unipotent groups

JdoeLet $k$ be a field of characteristic 0 (not necessarily algebraically closed), let $G$ be a connected split reductive group over $k$ and let $\mathfrak{g}$ be the Lie algebra of $G$. Let $X \in \mathfrak{g}$ be a nilpotent element. Does there exist a unipotent subgroup $U$ of $G$ such that $X$ ...

3
Q: Has anyone ever written a novel or short story composed of only dialogue?

DaydahThe participants describe everything needed for the story to continue, within the conversation. The environment, the emotions, everything. The reader gets to "see" it all through their words. Has it been done before?

posted on July 21, 2019

From steve antwan and tagged as ramps-1.4,ramps

3
Q: What would be an ideal fidelity measure to determine the closeness between two non unitary matrices?

Tejas ShettyThe Hibert Schmidt norm $tr(A^{\dagger}B)$ works well for unitaries. It has a value of one when the matrices are equal and less than one otherwise. But this norm is absolutely unsuitable for non-unitary matrices. I thought maybe $\frac{tr(A^{\dagger}B)}{\sqrt{tr(A^{\dagger}A)} \sqrt{tr(B^{\dagger...

2
Q: How does mathematics work?

Craig FeinsteinIf I am given a parking lot with ten thousand cars and I want to determine whether one of the cars is orange, the only way I can do this is go through the parking lot examining each car until I find one that is orange or I examine each car and conclude that there are no orange cars. However, if ...

18:16
6
Q: Making an example from 'Clean Code' more functional

SG_90I'm a C++ dev, and I've recently started working my way through Clean Code*. Whenever I encounter an example I think I could improve, I try to re-implement it in C++. On pp. 28-29 there is an example with a message building class, which looks like this when implemented in C++ (includes and names...

2
Q: Binary Logit: A statistically insignificant predictor become significant after exclude some observation

ajjummaI am currently trying to explore the determinants of management turnover using binary logit. In robustness check, I have added more control variable (Industry) to see whether the same results hold. Surprisingly, almost all effects stay the same (economically and statistically), but a statistica...

18:32
1
Q: Will a ThunderBolt 3 (USB-C?) to ThunderBolt 2 cable allow me to use a MacBook Pro as second monitor?

Grant SmithYesterday I brought a iMac (Retina 5K, 27-inch, 2017) which has two ThunderBolt 3 (USB-C?) ports. I also have a MacBook Pro Late 2013 which has two ThunderBolt 2 (I think) ports. If I buy a ThunderBolt 3 to 2 cable. Would I be able to use the MacBook as a second monitor?

6
Q: Why does airflow separate from the wing during stall?

LandellIs there any explanation for what causes the airflow separation from the airplane wing, that triggers a stall? To be more precise, what is the detailed explanation of the physics for why flow separation occurs at certain speeds & angels-of-attack? Or are engineers still working on this explanat...

18:47
1
Q: Fitting two-dimensional data

Vaggelis_ZFor this question, I cannot use random sample data. So the actual data can be found here. The data file contains three columns, where the first two are the coordinates $(x,y)$, while the third is the value of a function $f$. Now we plot them, thus obtaining the shape of $f$ data = Import["L1.dat...

1
Q: Do I care if the housing market has gone up or down, if I'm moving from one house to another?

BrondahlI can see several cases in which it obviously IS important if the market is high or low. e.g: if I'm buying my first house if I'm retired and selling my last house if I'm moving to a very different country/city, whose housing markets aren't very tightly bound together. "negative equity" where s...

19:03
9
Q: Difference between string += s1 and string=string +s1

Naman One of my code is giving time limit exceeded when I am using fans = fans + s[i] while when I am using fans += s[i] it is being accepted ...don't know why this happens? fans = fans + s[i] // gives Time limit exceeded fans += s[i] // runs successfully

2
Q: Does any picture file format embed author, title etc.?

S MeadenDoes any picture file format embed author, title etc.? I'm currently playing with ffmpeg and such info ships with a video file and I thought it useful. I was wondering if an image file can also pack these attributes. I realise if they did exist they'd probably be easily changed and so won't...

19:22
3
Q: Trivial non-dark twist in dark fantasy

KirattaI am writing a rather dark, grey fantasy story. It is supposed to feature a twist that turns the antagonist's goal to not to be evil at all (just misjudged) and really trivial (despite requiring large dose of effort). The protagonist changes for the worse, but I still get the feeling that that ki...

19:35
2
Q: Redirection operator, standard input and command parameters

Slava K.I'm following "The Linux Command Line" by William Shotts. From what I understood, the > operator saves standard output to file, and < take standard input from file. If the keyboard is the default standard input and < only takes that input from some file, why is ls -l not equivalent to ls < so...

6
Q: How to declare an array without specifying its size, but with an initializer inside a class in C++?

Yan B.It is allowed to declare an array without explicitly stating its size, if it has an initializer: // very fine: decltype(nums) is deduced to be int[3] int nums[] = { 5, 4, 3 }; However the same doesn't work when the array is declared in a class: class dummy_class { // incomplete type is n...

5
Q: Book about an amphibian race at the centre of the Earth

AbbyI’m after a book about an amphibian race, a guy found a creature, there was a scientist involved, the thing learnt English and lives in an advanced civilisation under the Earth that can be accessed through a cave under the sea. Something about peanut butter and jelly sandwiches and down there you...

GIS
GIS
19:52
1
Q: How to get all the sub-rectangles (subgeohashes) of a given geohash

tinlyxI am trying to use geohash to generate a grid of rectangles to cover an area. But I am not very familiar with the coding system of geohash. My question is: If I have a specific geohash gh of 3 characters, how do I get a list of all 4,5,6-character geohashes that are contained in the ST_GeomFromG...

20:03
6
Q: Structuring a 2D array from a pandas dataframe

henryI have a pandas dataframe: import pandas as pd import numpy as np df = pd.DataFrame(columns=['Text','Selection_Values']) df["Text"] = ["Hi", "this is", "just", "a", "single", "sentence.", "This", np.nan, "is another one.","This is", "a", "third", "sentence","."] df["Selection_Values"] = [0,0,0,...

4
Q: What is the origin of "Wonder begets wisdom?"

MatthewSocrates famously said, "Wonder begets wisdom." Where is this passage from and what is the full text translation? There seems to be some great missing context...

1
Q: Is art a form of communication?

MossmyrI recently got into a discussion where the other person claimed that art is a form of communication. Bearing in mind that the definition of art is disputed, would you agree that a work requires an emotional state or idea to be transmitted between two parties for it to be considered 'art'? If so, ...

20:27
5
Q: Discretisation of region intersection in 3D

JackySnoepIf I try to discretise the intersection (BoundaryDiscretizeRegion), of a shell in a cuboid, some of the regions (that are found with RegionIntersection) are lost in the discretising process. I tried several of the options for BoundaryDiscretizeRegion but none seem to give me both the regions back...

2
Q: Conditional statement in a function for PS1 are not re-evalutated

Mr. MadaminI'm using a function to dynamically generate output for PS1. There are a couple statements that check if node and package.json exist, and if git and .git folder exist to display node version or the git branch. If none exist it just outputs the User$. The problem is when user goes into another fo...

20:44
2
Q: Father as an heir

Kazi bácsiIn Parashat Pinchas we learn about the rules of inheritence. A son inherits first. This is implicit from the first statement of the Parsha. It says that if the deceased person didn't have a son, then the daughter inherits (27:8). didn't have a child, then the brothers inherit (27:9). didn't hav...

20:55
4
Q: Polynomials with natural coefficients arising from exponentiation and sums

Mario RománIs there any nice characterization of the class of polynomials can be written with the following formula for some $c_i , d_i \in \mathbb{N}$? Alternatively, where can I read more about these? do they have a name? $$c_1 + \left( c_2 + \left( \dots (c_k + x^{d_k}) \dots \right)^{d_2} \right)^{d_1}...

21:05
11
Q: Book in which the "mountain" in the distance was a hole in the flat world

SproutScience fiction novel or short story. Characters were lost or crashed or something on a new-to-them world and were making for a mountain they could see in the distance. But when they reached the mountain, it turned out to be a hole blasted by an asteroid through the "world" they were on, which tu...

1
Q: Animating the result of numerical integration

RoboticistI've animated a dynamics as follows in Python. However, I'd like to have the same in Mathematica (whose graphics output, in my view, is fancier than Matplotlib). #!/usr/bin/env python # -*- coding: utf-8 -*- from scipy.integrate import odeint import matplotlib.pyplot as plt import numpy as np ...

3
Q: Can two waves interfere head on?

VisalCan two waves (like sound or electromagnetic waves) interfere head on? If yes, and suppose they are out of phase with each other and thus interfere destructively, where does the energy of the waves go?

21:26
6
Q: A bicolour masyu

jafe This is a bicolour masyu puzzle. Instead of making one continuous loop, the goal is to make two separate loops, one blue and one red. The coloured circles must be used for the loop of the same colour, whereas black circles can be used for either colour.

ELL
ELL
2
Q: "move up the school" meaning

dan "As he moved up the school, he gathered about him a group of dedicated friends; I call them that, for want of a better term, although as I have already indicated, Riddle undoubtedly felt no affection for any of them. Harry Potter and the Half-blooding Prince I'm not sure what "moved up...

21:42
3
Q: Do I have to mention my main characters age?

LymabaI finished my novel and realised that I never mentioned my main characters age. In chapter two I said that she in in her twenty's, but that's the only mention of her age. I know that she is twenty-three, should I state this in my novel or is it okay to leave her age vague?

21:54
2
Q: What would be the effects of (relatively) widespread precognition on the stock market?

Tobi AlafinI am working on a story in which around 1% of the world population has at least some semblance of a metahuman ability. Many metahuman abilities are advantageous in traditional employment, and I imagine that many of those who possess such abilities would put them to economic uses. For precognition...

2
Q: Why is there no video of the first steps of Apollo 16 and 17?

PearsonArtPhotoIn doing research in to the first words said on the surface of the various Apollo astronauts, I found there was no video of Apollo 16 and 17, at least until they had been on the surface for a while. Why is that?

1
Q: What is the minimum wait before I may I re-enter the USA after a 90 day visit on the Visa B-2 Program?

Izzy BenjaminWhat is the minimum wait before I may I re-enter the USA after a 85 day visit on the Visa B-2 Program?

22:12
1
Q: Three phase systems - are there any single phase devices that are connected between two phases instead of between one phase and neutral?

user3711671In star system, single phase consumers are connected between a line and neutral but are there any single phase devices connected between two phases (would that even be considered a single phase device?)?

1
Q: Rule of thumb to choose right mix of Rodinal developer?

scamanderMassive Dev. Chart has around 7 kinds of combination of Rodinal mixture for TriX400: from 1+24 to 1+100. I have TriX400 used at box speed or pushed/pull. Is there any rule of thumb to choose the best Rodinal mix at certain film exposure type above?

TeX
TeX
22:28
1
Q: How to create complicated tables (multiple nested columns and rows)

Anna VopuretaI have an image of a table that I want to replicate but I can't figure out how to do the multiple rows part (see left side of column) and the multiple columns part (see right side). Is there a general way to do this? How do you go about creating such tables? The numbers are irrelevant, I'm looki...

RPG
RPG
7
Q: Do you need to have the original move to take a "Replaces:" move?

kdubsWhen leveling in Dungeon World, if you choose a move that has a "Replaces: X", do you need to have the X move? For example, a thief wants to take the move "Dirty Fighter". It states "Replaces: Cheap Shot". Does the thief need to have taken "Cheap Shot", or can he just choose "Dirty Fighter"?

TeX
TeX
22:48
1
Q: \setcounter{} is not affecting numbering

Hadi FarahI am trying to write my master thesis using a header file given by chair. I'm trying to use \subsubsection{} which did not include any numbering, a quick google search reveals I need to use \setcounter{} The format is as follows, I have a master.tex file which inputs thesis_header.tex and the c...

1
Q: Remove side menu(right side) from finder

Bhavin RamaniWhen I open any Finder window it appears with options in the right side. I can hide it by dragging it to end. But if I open a new window of the finder it appears again. So, please help me to hide that options menu in Finder. OS: Mojave 10.14.5

5
Q: Another "name-that-distribution" question

jthThe density $$f(s)\propto \frac{s}{s+\alpha}e^{-s},\quad s > 0$$ where $\alpha \ge 0$ is a parameter, lives between the exponential ($\alpha=0$) and $\Gamma(2,1)$ ($\alpha \to \infty$) distributions. Just curious if this happens to be an example of a more general family of distributions? I do not...

23:32
1
Q: What's the difference between 1kb(64x16) and 1kb(128x8) for EEPROM memory size?

GenericEntityIn addition to the question in the title, I have the following subquestions: I'm guessing 64x16 means something like 64 cells of 16 bytes each. Is this accurate? What is the significance (if any) of the memory being 64x16 vs 128x8? What is the specific term (if any) for this (i.e. 1kb being co...

2
Q: Have any lunar probes used a cold shield?

Magic Octopus UrnI was reading this question and wondered if there has ever been a design idea which could shield a rover from the 14 day heat and cold cycle when on the surface of the moon. I was imagining some sort of dome-like structure which is retractable or something along those lines. However Im unsure th...

23:52
2
Q: Can a crisscrossed metallic skeleton resist earthquakes for buildings?

Chong Lip PhangTo follow up with my previous question on the seismic design of buildings, I would like to ask if it makes sense to support buildings with strong thick 'crisscrossed' metallic frames. I have the impression that an 'X-structured design' provides good structural integrity, as commonly seen in cons...

7
Q: Killing a star safely

Henry TaylorA messenger from the stars just arrived in peace but has brought horrible news. A vast swarm of planet devouring phototropic insects are approaching from deep space and our only hope is to obscure or snuff out our sun until they pass by. The messenger provided a copy of the galactic encyclopedia...

3
Q: Infinite points on circle

user237118Can we say that circle has infinite points? What if then I took one point out. Does it matter. And then if we took half the infinite points of the circle out of it and still can it be called circle?

4
Q: What does this chess proverb mean?

lolololol ol "Chess is a sea where a gnat may drink from and an elephant may bathe in." ~ Anonymous The above proverb is scattered everywhere throughout chess literature, folklore and even software. I have never fully understood its meaning, however. Does the gnat represent a patzer and the elephant re...


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