"Failed to open VDPAU backend libvdpau_nvidia.so" error even though not using MPlayer
How to identify the process that's sending error messages to terminal?
Why can´t we assign a new string to an char array, but to a pointer? Referencing without captions appearing but keeping numbering What is the relationship between redshift and conformal time ?   For example in a paper i found:   taking $z_e = 3234 $ at the time of radiaton-matter equality yields the conformal time $\frac{\eta_e}{\eta_0} = 0.007$ and taking $z_E=0.39$ at matter-$\Lambda$ equality yields $\frac{\eta_E}{\eta_0}=0.894$ and setting redshift at decoupling $z_d=1089$ yields $\frac{\eta_d}{\eta_0} = 0.0195$  where $\eta_0$ is the present decoupling time.  Further some cosmological parameters are given as :  $\Omega_r = 8.36 \times 10^{-5}, \Omega_m = \Omega_b + \Omega_{dm} = 0.044 +0.226, \Omega_\Lambda = 0.73,  H_0=0.72$  Now how can i calculate all those $\eta_e, \eta_E, \eta_d, \eta_0$ from given redshift values and/or above parameters ? I searched whole of my text books trying to find an explicit relation for conformal time $\eta$ but all i got was $ \mathrm{d}t=a(t)\mathrm{d}\eta$. Any help would be very helpful. How to solve "sudo: /etc/sudoers.d is world writable" Draw a vertical line over the entries of a column in an array I'd like to draw vertical/horizontal lines over the entries of a column/row in an array. I find the method to draw horizontal lines at . But when I used the same way to draw the vertical lines. It didn't look well. My codes are:  \usepackage{tikz} \usetikzlibrary{calc} \newcommand{\tikzmark}[1]{\tikz[overlay,remember picture] \node (#1) {};} \newcommand{\DrawLine}[3][]{% \begin{tikzpicture}[overlay,remember picture]     \draw [#1] ($(#2)+(0,0.6ex)$) -- ($(#3)+(0,0.6ex)$); \end{tikzpicture}% }%  \begin{displaymath} \left[ \begin{array}{cccc} \tikzmark{11}{15} &amp; 0 &amp; \tikzmark{13}{0} &amp;0\tikzmark{14} \\ 0 &amp; 50 &amp; 20 &amp; 25 \\ 35 &amp; 5 &amp; 0 &amp; 10\\ \tikzmark{41}{0} &amp; 65 &amp; \tikzmark{43}{50} &amp; 65 \end{array} \right]. \DrawLine[black,thick]{11}{14} \DrawLine[black,thick]{11}{41} \DrawLine[black,thick]{13}{43} \end{displaymath}   The result looks like     But the result I want is     Does anyone know how to fix this? Thank you. When I compile the Python code below, I get      IndentationError: unindent does not match any outer indentation level     import sys  def Factorial(n): # Return factorial     result = 1     for i in range (1,n):         result = result * i     print "factorial is ",result     return result   Why? Unable to find minimized terminal I just installed 11.10 and found that once I minimize the terminal window, I can't bring it back. All other Windows are getting minimized to the Unity launcher and I can relaunch them from there. If I go to the launcher and click on terminal a new terminal session is created and the old one is lost completely. This is the first time I am facing such a problem and all my previous installations of 11. 10 didn't throw up any such behaviors. Any suggestions? The Wikipedia  has a derivation of the Klein-Gordon equation.  It gets to this step:  $$\sqrt{\textbf{p}^2 c^2 + m^2 c^4} = E$$  and inserts the QM operators to get  $$\left( \sqrt{ (-i \hbar \nabla)^2 c^2 + m^2 c^4 } \right) \psi = i\hbar\frac{\partial}{\partial t} \psi$$  The article then says     This, however, is a cumbersome expression to work with because the differential operator cannot be evaluated while under the square root sign. In addition, this equation, as it stands, is nonlocal.   To fix this, the first equation is squared instead to get  $$\textbf{p}^2 c^2 + m^2 c^4 = E^2$$  after which the QM operators are inserted and the expression is simplified to get  $$-\hbar^2 c^2 \nabla^2 \psi + m^2 c^4 \psi = -\hbar^2 \frac{\partial^2}{\partial t^2} \psi$$  A couple things I don't understand.  First, are the solutions to this differential equation not exactly the same as the solutions to the first differential equation?  Both sides of the starting equation were squared, so it seems to me that regardless of the particular form of the resulting differential equation, both of them should have the exact same set of solutions.  Secondly, why is the first differential equation cumbersome to work with?  It seems like it would in fact be easier to work with, since the operator under the square root could be expanded in terms of a Taylor series and then you have an equation that is first order in time.  And finally, can someone elaborate on what nonlocal means? The linked article on the Wikipedia page didn't entirely help me understand it. Pollinator abundance---sampled two years, fixed or random effect? I'm trying to construct several GLMMs with my thesis data and I can't solve this question. I have data on pollinator abundance and fruit set from plant individuals (with different treatments - related to a pest infection -) sampled at six study sites (spatial replicas) and during two consecutive years (time replicas). The problem is that not all individuals (plants) were sampled in both years (because of lack of bloom). My question is: How should i use &quot;Year&quot;, as random effect or as fixed effect? I constructed three candidate models and compared the AIC: a) Response variable ~Predictor variables + (1 | year/plant) + (1 | site/plant) b) Response variable ~Predictor variables + (1 | year) + (1 | site/plant)  c) Response variable ~Predictor variables * year + (1 | site/plant) Option a) had the lowest AIC and the highest R2, but I read in some papers that is not correct use a variable with less than five levels as random effect ... so, anyone could help me? Loading a properties file from Java package What does the 'static' keyword do in a class? Why do some devices have 200V on the case? I recently got a desktop LED lamp, and I feel a "strange" slight vibration when touching the metal case. I found that other devices also have high voltage on their case.  What is the reason/trade-off to design the PSU that way? Are "real" transformers inefficient? Even if it's harmless, why is the high voltage connected to the metal case, and not just through insulated wires?    When I turn the lamp on, the setup in the picture measures the power line (220V) 214Vpp (59Vrms). When I also touch the metal case, the voltage drops down to around 30V.  AC adaptor: How do I install a fingerprint reader on Lenovo ThinkPad? I have a  with a fingerprint reader:    How to make Ubuntu recognise it and use it for login?  I already tried:  sudo add-apt-repository ppa:fingerprint/fingerprint-gui sudo apt-get update   ... but this GUI did not recognizes my device. Does anyone knows any other option? Specifying element type for DXF creation using ogr2ogr I am trying to create a DXF from a Polygon Shapefile using ogr2ogr:  ogr2ogr -f DXF parcels.dxf parcels.shp   The problem is that the polygons are written as hatch elements.    How do I specify that ogr2ogr should create LWPOLYLINE elements (Or any other )?  I have tried this from command line and from QGIS 'save as' option with the same result.  I don't remember this being an issue in the past, but seems like it started with GDAL version 1.10.x. "States Party to" or "State Parties to" or "States parties to"? When discussing a treaty or international agreement, which is correct?  "There are 100 states party to the treaty." (for example, as used )  Or:  "There are 100 state parties to the treaty." (for example, as used )   Or: "There are 100 states parties to the treaty."  (for example, as used ) \nameref breaks for the star versions of section, paragraph when titlesec is loaded. I have a document that numbers paragraphs by default, but I have a few I do not want to number but would like to refer to. These are marked with \paragraph*, however, if the titlesec package is loaded at the same time, it causes nameref to display an empty string (the link box of hyperref is still visible).  MWE:  \documentclass[12pt]{article} \usepackage[sf]{titlesec} %comment this out and it works fine. \usepackage{hyperref} \begin{document} \section{Sections} \label{sec} This is \nameref{sec} \paragraph{A named Paragraph} \label{par} This is \nameref{par} \paragraph*{A starred named Paragraph} \label{par:star} This is \nameref{par:star} \end{document}   I suspect titlesec causes this defect for ALL star variants of sectioning commands but have not tested this. For me only paragraph* is relevant however a fix for all variants would be the best.  I have a hunch it might be related to this:  however this happens to go way beyond my latex knowledge and is just "magic" for me. Prove that the $\lim_{(x,y) \to (0,0)}h(x,y)$ Does not Exist using Polar Coordinates Let $h(x,y)=\frac{x^5y}{2x^{10}+y^2}$. How would I prove that the $\lim_{(x,y) \to (0,0)}h(x,y)$ Does Not Exist?  I think that we might use polar coordinates, but I am not sure. Sci-fi book, blue critters than only some people can see, kids fight the critters as they feed off energy and are a threat Dual boot => Triple boot A 256GB SSD has Windows-10 and 16.04 installed.  BIOS not UEFI.  A charity I work with requires me to use Quickbooks Desktop on Windows.  The plan is to ghost the existing system to a 512GB or larger SSD and create a third bootable Windows 7  partition for performing charity activities.   Is this possible to have a third partition? Is there a good example you have used as a guide? Is triple booting with two Windows partitions different from 2 Linux partitions?   If you have done this before ( with GRUB) please indicate this in your response: lessons-learned are appreciated.  Thank you What is the best way to replace the file browse button in html? I know that it's possible to replace the browse button, which is generated in html, when you use input tag with type="file.  I'm not sure what is the best way, so if someone has experience with this please contribute.