Bug Definition and 105 Threads

I am trying to copy the contents of this PDF into another document (it doesn't seem to matter which document type). No matter how much or how little I copy into the clipboard, no matter whether I paste it into a text editing field - an email, or notepad - I get the same thing: The text I'm...

Something is broken with "find all content by". If I go to some people's pages, e.g. https://www.physicsforums.com/members/hutchphd.635497/ go to "Find" and "Find all content by", it is empty. Other people, like @Greg Bernhardt have messages show there. I do not know what makes this happen...

I have tried on different machines and browsers (Edge, Chrome, Firefox, Safari); the latest upgrade of Windows 10, as well as up-to-date MacOS 14. When clicking the 'CONTACT' button in the footer bar, I do not seem to be logged in on that page. Trying to click 'LOG IN' in the header bar on that...

Does a bug hitting your windshield slow down your truck?

Every time that I click to comment on a Insight Blog article I get redirected to a new page that says: But clicking there gets me to back to the forums and not to the Insight article. Is this a bug?

I got an alert yesterday for a post by stefanoquattrini. Here's a screenshot showing it, where I've long-pressed it so you can see the URL. Note that it says "quoted your post". But physicsforums.com/posts/7060332 quotes Sagittarius A-Star, not me. The link in the post's quote header says...

My second attempt. Somebody asked, "What is Research"? Would someone here with physical science Phd tell the meaning of "Research"? My own way to give a meaning is to compare with cooking food; but that it is just far more precise. I used copy&paste to put in the title.

It seems as though it's not only with latex, but with previewing in general. Sometimes restarting Firefox will fix it for me, but I've restarted it 2x now and nothing. It just doesn't preview. You hit preview, it locks out editing, but doesn't show you what your post looks like

Remember the Y2K bug, 22 years ago? Now we have the Y2K22 bug. Microsoft Exchange servers overflowed a 32-bit integer at the beginning of the new year, causing them to stop processing e-mail...

hello I own mathematica 10.02 it is virtually impossible to solve PDE's ,even with NDSolve,if the initial conditions contain a derivative I write Derivative[1,0] [0,x] == f[x] I mean the first t derivative of u[t,x] for x at t=0 is f[x] I own a book based on Mathematica 10.3 Even if a...

I(i)w(i)= I(f)w(f) I(i)= 1.08 x 10-3 kg·m2 w(i)= 0.221 rad/s I(f)= mr^2 + I(i) = (5 x 10^-3)(.138)^2 + (1.08 x 10^-3) (1.08 x 10-3)(.221) = ((1.08 x 10^-3)+9.22 x 10^-5))w(f) w(f) = (2.3868 x 10^-4)/(0.00117522) w(f)= 0.203094 rad/s This is my attempt; however, I cannot seem to get it...

Given a bug that's walking counterclockwise around on the surface of a lazy susan (which itself is sitting on frictionless bearings), wouldn't the the friction between the bug and the lazy susan (which is needed to be able to walk) apply torque (no matter how negligible) that accelerates the...

I've encountered this really weird bug in Python. Below is a snippet from a class method. The error occurs where I've placed the two print statements. The update method has absolutely nothing to do with Cprev. The update function changes the value of the attribute self.C. However, the two print...

Twenty years ago, we were waiting to see whether the billions of dollars and thousands of person years spent finding and correcting the Y2K problem (aka Millennium Bug) had been successful. To remind you: there were three major problems (and a few minor ones - for full details see the paper...

This has been going on since I first got this laptop (Acer Aspire 5) with Windoze 10. I open my Explorer window to look through some files, and if I leave it to go to another app, it spontaneously disappears. This happens whether I alt-tab to another full screen window or even if I set it up...

Been tracking down the most unusual bug I've seen in 40 years of programming (mostly in assemlber and C). It manifests in the test suite for an object oriented XBase language implementation that's been ported everywhere from Palm Pilot to OS/2 to the Blackberry tablet to Windows to, now, Qnx7...

I would like to know what causes bugs, on the software side. Bug was not at all the term used for software but over time, it has evolved into what I think is the result of carelessness, poor development and lack of knowledge. In modern computing, bugs occur in software all the time. But why does...

Homework Statement A bug crawls outward from the center of a compact disc spinning at 210 revolutions per minute. The coefficient of static friction between the bug's sticky feet and the disc surface is 1.1. Homework Equations (static friction)(Gravity) = (centripetal force) This may be wrong...

I calculated a simple complex function integration using Mathematica 11. As the screenshot shows, the only difference between the two inputs is that I set a = 1 in the second one. However, the two outputs differ by a factor of 2. What's wrong? Is this a bug?

Hi, Not sure if here is were i should report the bug. If you make a plane and a sphere with a rigidbody, at some specifics altitudes, the sphere goes trough the plane. To reproduce it easily, i put the sphere 3.5 units higher than the plane and change the sphere scale to (0.2 , 0.2 , 0.2). This...

I want to know how fast the space shuttle would have to hit the Earth to unleash the same kinetic energy as the asteroid that killed the dinosaurs. I've already determined that it's relativistic, by showing that Newtonian physics gives a v greater than c But once I plug in the equations, I get...

Homework Statement A cockroach crawls with constant speed in a circular path of radius b on a phonograph turntable rotating with constant angular speed omega. The circle path is concentric with the center of the turntable. If the mass of the insect is m and the coefficient of static friction...

I am testing the MCNPX plugging MCUNED to make calculations with neutron generators. After the compilation many examples to test the installation are provided. But one of them (I attached the code below) starts but it never finish. Just keeps in the first rendezvous. I first though in a problem...

In this movie Eye in the Sky about drone deployment in the middle east. This is this small electronic beattle which can fly and has built in camera to spy inside houses. Is this technology real? Where can one get it? Should there be none, what is the smallest drone you saw that has good...

http://www.sciencealert.com/a-bug-in-fmri-software-could-invalidate-decades-of-brain-research-scientists-discover Could this be true?

Hi people, I've "enrolled" into the edx MITx 6.00.2x course on python and data science, but I don't plan to get a certificate and I started so late that all the problems I'm facing aren't due anymore so I think this gives me the right to seek help here. Basically the task is to simulate some...

I can't upload the notebook I guess, that would be a nice feature mods! (.nb extension) But here is my code , there seems to be a problem with integrating separately and then combining. $Assumptions = 0 < r < 1 && 0 < z < 1; FUNCTION = Expand[-(Pi*(-1 + r)*(-12*z + r^2*z + r*(-12 +...

Homework Statement So, I'm getting two blocks of zeroes in my console output from this program. After much effort (and stack exchange) I'm still unable to get it working. Could someone point me to a solution? Mod note: Added code tags Homework Equations #include<iostream> #include<iomanip>...

messed up original post: "Hunter is having a top cover re‑designed" no period. now click the cursor right before the d in designed. hit tab, it will tab a single space. not a full tab. change "Hunter" to "Mike" or any other name, it will do a full Tab. try a word like "re-test" or...

Greetings, I've just been having an issue recently and don't know how to approach it. I did an REU over the summer with a professor and I performed quite well. When I mentioned I might apply for the NSF GRFP this fall, the professor told me that if I wanted him to proofread my application essay...

While quoting a post earlier I came across the following interesting behaviour. I pasted a QUOTE tag into a place where the person I was quoting had used large bold text, and accidentally made the QUOTE tag large bold text. This seems to have cause the behaviour below - there is only one QUOTE...

So I'm writing a short subroutine to compute a QR factorization of an (mxn) matrix using the Householder method. To test this, I'm computing the factorization of the matrix 12 -51 4...

Hi all, I am to compute A = QR using the Modified Gram-Schmidt algorithm. I need to find the error using the one norm of : (Q transpose * Q) - I. Here is my code: %Modern Gram Schmidt p=zeros(5,5); e=zeros(5,5); g=zeros(5,5); for k=1:n; p(:,k)=(A(:,k)); end %j=k, i=u, r=g, q=e, v=p for...

I am clueless. Here's the model I tried to follow: g(a):=a^2-1; f(a,b):=a+g(a)-b; f(a,b); With output −b+a^2+a−1 Which is 1)Define a function in terms of some variable(s). 2)Define another function in terms of some variable(s) and in terms of the function defined in 1). 3)Evaluate the function...

Homework Statement "A drinking straw of length 1.5a and mass 2m is placed on a square table of side a parallel to one of its sides such that one third of its length extends beyond the table. An insect of mass \frac{1}{2}m lands on the inner end of the straw (ie, the end which lies on the...

Homework Statement "You have a 1 km long rubber band with one end attached to the wall, and the other in your hand. The bug begins to crawl towards you on the rubber band, starting from the wall, at a rate of 1 cm/sec. As he crawls the first centimeter you extend the rubber band 1 km; when he...

Integrate[f[qs] DiracDelta'[qs (1 - 1/x)], {qs, -\[Infinity], \[Infinity]}, Assumptions -> 0 < x < 1] Integrate[f[qs] DiracDelta'[qs - qs/x], {qs, -\[Infinity], \[Infinity]}, Assumptions -> 0 < x < 1] This is on Mathematica 8 for windows. The results differ by a sign. They are effective...

If you haven't, you should rethink that thanks to the heartbleed bug. Your passwords on a supposedly secure website most likely are not secure, thanks to this bug. The last two xkcd.com cartoons depict the problem quite nicely:

Homework Statement A square metal frame in the vertical plane is hinged at O at its centre as shown in the figure. A bug moves along the rod PN which is at a distance ##l## from the hinge, such that the whole frame is always stationary, even though the frame is free to rotate in the vertical...

I have found that while these two should be the same, mathematica does not evaluate them equally. Integrate[(a + b el + c el^2) DiracDelta[u], {u, 0, 1}, {el, e1, e2}] Integrate[ Integrate[(a + b el + c el^2) DiracDelta[u], {el, e1, e2}], {u, 0, 1}] I believe the second one is correct...

I don't know python, yet I am trying to code something, just for fun. But I have hit some strange obstacle and I don't know if it is a bug in my Python version (dated, it is over a year old, under Raspbian), or is it me misunderstanding something? pattern = re.compile('\[(\d+)\]\[(\d+)\](.*)')...

Please try: Integrate[((x - 1)^2/x) (1 - y), {y, 0, 1}, {x, 0, 1}] Integrate[((x - 1)^2/x) (1 - y), {x, 0, 1}, {y, 0, 1}] on your version. My Options[Integrate] GenerateConditions-> Automatic. In the first case, it gives -3/4, the second is divergent. For some reason when the...

Homework Statement A small 13.0g bug stands at one end of a thin uniform bar that is initially at rest on a smooth horizontal table. The other end of the bar pivots about a nail driven into the table and can rotate freely, without friction. The bar has mass 65.0g and is 120cm in length. The...

Homework Statement A small 13.0g bug stands at one end of a thin uniform bar that is initially at rest on a smooth horizontal table. The other end of the bar pivots about a nail driven into the table and can rotate freely, without friction. The bar has mass 65.0g and is 120cm in length. The...

This is my own code, and it won't compile with gfortran. All I want to do is extract the location of the cell with the minimum value in an array. A seemingly simple task but one that does not work with the intrinsic function minloc, for reasons I do not understand. The error message...

A .5g insect rests on a compact disc at a distance of 4cm from the centre. If the coeffiecient of static friction is .51 what is the maximum velocity the insect can experience without slipping off? I am lost, can someone help ?

A well-known bug in vBulletin (the software of this forum) is the 50-character bug. Try this: Nowisthetimeforallgoodmentocometotheaidoftheircountry. This "word" is just over 50 characters long, and you can see that vBulletin forces a space in-between the n and the t of "country", right at the...

Years ago I remember watching a "documentary?" on TV about our skin or hair (my best guess is hair). It was about all of the microscopic "bugs" that live on us. And the best I remember, there was one that looked like a lobster. Anyone know the name of this "bug"? (I've tried Google with no...

Hi All, A slight problem I've had with a function defined by a numerical integral. The definition is f[q_,c_,n_]:=NIntegrate[\[Beta]*BesselJ[0,q*\[Beta]]*(E^(I*c*((\[Beta] BesselK[1,\[Beta]] HypergeometricPFQ[{1},{1+n/2,1+n/2},\[Beta]^2/4]+n BesselK[0,\[Beta]]...

Hi guys, For one more time I need your opinion in a kind of strange issue, which escapes my understanding. Performing a single line to ground short circuit calculations (Low Voltage Side) in a simple Generator power plant using a step up to transformer, we can observe the two following...