I wanted to make a bash script that takes a random picture from a folder and sets it as the desktop background. I figured out the algorithm (it's not hard) but I can't find a command that would change the background picture if you give it the path to the picture.   I found gconftool for bash 2.~ and gsettings for bash 3.~, but i have GNU bash, version 4.3.42(1)-release on Ubuntu 16.04 LTS and these don't work.
I have a script that updates my desktop background every day with the NASA APOD. Since upgrading to 11.10, that script stopped working, presumably because I'm using gconftool-2 to actually update the desktop background. Is there a new way to do this under Unity?
Undefined Symbol ___gxx_personality_v0 on link I've been getting this undefined symbol building with this command line:  $ gcc test.cpp Undefined symbols:   "___gxx_personality_v0", referenced from:   etc...   test.cpp is simple and should build fine.  What is the deal? I'm splitting a string by three different characters but I want the output to include the characters I split by. Is there any easy way to do this? Hill Cipher known plaintext attack I know a plaintext - ciphertext couple of length 6 for a hill cipher where its key is a [3x3] matrix.  Based on what I've read and learned, to attack and crack keys of [n x n], if we know a plaintext - ciphertext duo of length $n^2$ then we have our set of n equations with n variables, and this is generally solvable. However in my case there is only length of $6$ instead of $n^2 = 9$ .   My question is, how will I solve this problem and find the key? Or, since this is an obvious homework question, what should be my way of thinking? I cannot think of anything else but matrix multiplications and inverses but they do not help me at all. remove files when name does NOT contain some words How do I quickly switch between workspaces in unity? Unresponsive KeyListener for JFrame Can I rephrase the sentence "Can you explain this word to me?" into "Can you explain me this word." How can I avoid Java code in JSP files, using JSP 2? How do you parse and process HTML/XML in PHP? It seems that given a statement $a = b$, that $a + c = b + c$ is assumed also to be true.  Why isn't this an axiom of arithmetic, like the commutative law or associative law?  Or is it a consequence of some other axiom of arithmetic?  Thanks!  Edit: I understand the intuitive meaning of equality. Answers that stated that $a = b$ means they are the same number or object make sense but what I'm asking is if there is an explicit law of replacement that allows us to make this intuitive truth a valid mathematical deduction. For example is there an axiom of Peano's Axioms or some other axiomatic system that allows for adding or multiplying both sides of an equation by the same number?   In all the texts I've come across I've never seen an axiom that states if $a = b$ then $a + c = b + c$. I have however seen if $a &lt; b$ then $a + c &lt; b + c$. In my view $&lt;$ and $=$ are similar so the absence of a definition for equality is strange. Corrupt Backupt GPT Table Almost every time I turn my XBox on and start up Fallout 4, I am unable to use the "Continue" option because the most recent save is corrupt.  I instead use the "Load" option. Here, I can see that the last save I manually performed is perfectly fine, and load it with no problem. However, there is an additional, corrupt save with the same time stamp immediately after it.  This doesn't happen quite every time, but often enough that I'm surprised when there's no corrupt save waiting for me to delete it.  I've tried a few things to solve this, including exiting to the game's main menu before turning the XBox off, going out to the guide before turning the XBox off, turning it off immediately after saving, and waiting a while after saving.  Why do I get all these corrupt saves? Do others have this problem? How do I fix it? The  (or conjecture), suggests that black holes can be entirely described by their mass, angular momentum and charge. All other details of the BH formation are lost.  Is there a simple way of understanding why you would be able to tell the difference between a BH made from protons and one made from electrons, but not between one made from matter rather than anti-matter?  i.e. What is special about charge, and why aren't lepton number, baryon number, strangeness etc, also black hole properties? How is arccos derived? Stupid question but I need to understand:  If $ \cos = \dfrac{\text{adjacent}}{\text{hypotenuse}} $  What is arcosine? $ \text{adjacent} \cdot \text{hypotenuse}$? Is this the same for arcsine and arctangent? Can you give a simple intuitive explanation of IRLS method to find the MLE of a GLM? Background:   I'm trying to follow .  I understand the basics of MLE estimation: likelihood, score, observed and expected Fisher information and the Fisher scoring technique. And I know how to justify .    The question:   I can't understand even the first line of this method :(   What's the intuition behind the $z_i$ working variables defined as:  $$ z_i = \hat\eta_i + (y_i -\hat\mu_i)\frac{d\eta_i}{d\mu_i}$$  Why are they used instead of $y_i$ to estimate $\beta$?   And what's their relation with the response/link function which is the connection between $\eta$ and $\mu$  If anyone has a simple explanation or can direct me to a more basic-level text about this I would be grateful. Suppose I have a dataframe consisting of six time series. In this dataframe, some observations are missing, meaning at some timepoints all time series contain a NA-value. In R, one possible imputation package that can be used to impute time series data is Amelia. However, this package does not work for observations that are completely missing. Are there other ways to impute my data? For what it's worth, the amount of missing observations is less than 20% of all observations. Permission denied, are you root? I get this error whenever I try to install programs using the terminal:  home@ubuntu:~$ apt-get install myunity E: Could not open lock file /var/lib/dpkg/lock - open (13: Permission denied) E: Unable to lock the administration directory (/var/lib/dpkg/), are you root?   Also I'm unable to install updates using the terminal. I noticed an unexpected different line spacing of the titlepage what drives me crazy. The left page is the MWE, the right page without the \\ in front of Name.  \documentclass{scrartcl}  \begin{document}  \centering \Huge \textbf{UUUUUUUU UUUUUUUUU UUUUUUUUUUUUU UUUUUUUUUUUUU} \vspace{\baselineskip}\\ \textbf{UUUUUUUU UUUUUUUUU UUUUUUUUUUUUU UUUUUUUUUUUUU} {\rmfamily\Large \vspace{5\baselineskip}\\Name}  \end{document}     Any idea what causes this? Thanks alot!  Cheers, Stephan It started happening today... all of a sudden, no apparent reason!  Here's the output from df:   assp:~# df -k Filesystem           1K-blocks      Used Available Use% Mounted on /dev/simfs             6291456   1378384   4913072  22% / tmpfs                  8202680         0   8202680   0% /lib/init/rw tmpfs                  8202680         0   8202680   0% /dev/shm  assp:~# df -i Filesystem            Inodes   IUsed   IFree IUse% Mounted on /dev/simfs           55781934   83005 55698929    1% / tmpfs                2050670       2 2050668    1% /lib/init/rw tmpfs                2050670       1 2050669    1% /dev/shm  assp:~# df -h Filesystem            Size  Used Avail Use% Mounted on /dev/simfs            6.0G  1.4G  4.7G  22% / tmpfs                 7.9G     0  7.9G   0% /lib/init/rw tmpfs                 7.9G     0  7.9G   0% /dev/shm   Here's an actual entry from /var/log/mail.warn:   Dec 11 17:55:37 assp postfix/smtpd[30614]: warning: not enough free space in mail queue: 0 bytes &lt; 1.5*message size limit Dec 11 17:55:37 assp postfix/cleanup[30617]: warning: 4361D850D54: write queue file: No space left on device   . How to insert HTML to PHP DOMNode?