I wonder what the correct question form of the following sentence is:     Diet Coke has been made since 1982.   Is it correct to say "How long has Diet Coke been made for?" And should we use the preposition "for" or not? Or is there a better way to form a question?
I want to know if this is grammatically correct " How long would the conference be for?".
How to split 7.1 soundcard outputs to 4 stereo outs with ALSA Why singularity in a black hole, and not just "very dense"? Why does there have to be a singularity in a black hole, and not just a very dense lump of matter of finite size? If there's any such thing as granularity of space, couldn't the "singularity" be just the smallest possible size? I've fitted my model and am trying to understand whether it's any good. I've calculated the recommended metrics to assess it ($R^2$/ AUC / accuracy / prediction error / etc) but do not know how to interpret them. In short, how do I tell if my model is any good based on the metric? Is an $R^2$ of 0.6 (for example) sufficient to let me proceed to draw inferences or base scientific/business decisions?     This question is intentionally broad, to cover a wide variety of situations that members frequently encounter; such questions could be closed as duplicates of this one. Edits to broaden the scope beyond the metrics mentioned here are welcome, as are additional answers - particularly those that offer insight about other classes of metrics. Log4j Logging to a Shared Log File Is there a way to write log4j logging events to a log file that is also being written to by other applications. The other applications could be non-java applications. What are the drawbacks? Locking issues? Formatting? What does the 'rc' in `.bashrc`, etc. mean? Well, this is embarrassing. I feel like I just realised I don't know a loyal colleague's name after working with them for 10 years. "Hey, er... *cough!*, thanks for that great job you did on setting my aliases this morning..."  What do the letters rc signify in .bashrc, .kshrc, etc.?  If you know, please cite sources.  Even if you don't know, I'd also welcome unfounded assumptions, suggestions or alternatives if they're marked as such. I am trying to get Juju working on Windows 8 but I am running in to some errors when trying to get juju to see my ssh keys:  C:\Users\username&gt; juju bootstrap error: error parsing environment "azure":     read C:\Users\user\SkyDrive\Documents\Azure\ssh\: The handle is invalid.   I've added a public key I generated with putty to the directory above called azure  My environments.yaml file has this in it:  authorized-keys-path: C:\Users\user\SkyDrive\Documents\Azure\ssh\   Any ideas? Encouraging software publishers to use StackExchange as support mechanism I have a bunch of Spring beans which are picked up from the classpath via annotations, e.g.  @Repository("personDao") public class PersonDaoImpl extends AbstractDaoImpl implements PersonDao {     // Implementation omitted }   In the Spring XML file, there's a  defined:  &lt;bean id="propertyConfigurer"    class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"&gt;     &lt;property name="location" value="/WEB-INF/app.properties" /&gt; &lt;/bean&gt;    I want to inject one of the properties from app.properites into the bean shown above. I can't simply do something like   &lt;bean class="com.example.PersonDaoImpl"&gt;     &lt;property name="maxResults" value="${results.max}"/&gt; &lt;/bean&gt;   Because PersonDaoImpl does not feature in the Spring XML file (it is picked up from the classpath via annotations). I've got as far as the following:  @Repository("personDao") public class PersonDaoImpl extends AbstractDaoImpl implements PersonDao {      @Resource(name = "propertyConfigurer")     protected void setProperties(PropertyPlaceholderConfigurer ppc) {     // Now how do I access results.max?      } }   But it's not clear to me how I access the property I'm interested in from ppc? How do I move Ubuntu dock to bottom on Ubuntu 17.10 and later? Just upgraded from Ubuntu 17.04 to Ubuntu 17.10.  Please help me to shift the side bar (aka Ubuntu Dock) to bottom.   I tried running the following command which used to work with older Ubuntu releases   gsettings set com.canonical.Unity.Launcher launcher-position Bottom   but it's not working. Proof of Frullani's theorem How can I prove the Theorem of Frullani? I did not even know all the hypothesis that $f$ must satisfy, but I think that this are  Let $\,f:\left[ {0,\infty } \right) \to \mathbb R$ be a a continuously differentiable function such that $$ \mathop {\lim }\limits_{x \to \infty } f\left( x \right) = 0, $$ and let $ a,b \in \left( {0,\infty } \right)$. Prove that $$ \int\limits_0^{\infty}  {\frac{{f\left( {ax} \right) - f\left( {bx} \right)}} {x}}dx  = f\left( 0 \right)\left[ {\ln \frac{b} {a}} \right] $$  If you know a more general version please give it to me )= I can´t prove it. When I measure a 9V DC wall adapter power supply with a multimeter it shows 11.8V. When connected to my board this voltage lowers to 10V. Is this normal? Should I be afraid of toasting my  supplied board when using this adapter?  Edit: This regulator accepts up to 12V inputs. So that will be no problem. A second "9V" adapter yields 15V to the multimeter. Will this one burn my circuit? What is syntax highlighting and how does it work? I noticed that sometimes my code gets highlighted in different colors when rendered.   What is syntax highlighting? How does it work? Why isn't my code being highlighted correctly? How do I report a bug or request a new language? How do I use syntax highlighting? What languages are currently available on Stack Exchange? Can current be induced in a superconductor? A ring without the Invariant Basis Number property I was reviewing my homework and it seems I overlooked something crucial while proving some ring has no Invariant Basis Number property. This is exercise VI.1.12 in Aluffi's Algebra: Chapter 0  The setup: $V$ is a $k$-vector space and let $R = \mathrm{End}_{k}(V)$.   Prove that $\mathrm{End}_{k}(V\oplus V) \cong R^4$ as an $R$-module Prove that $R$ doesn't satisfy the IBN property if $V = k^{\oplus \mathbb N}$.   For the first, I used to the fact that $V \oplus V$ is both the product and coproduct (in $k$-Vect) of $V$ with itself to get the isomorphism. What I just realized is I only showed that the two are isomorphic as groups not $R$-modules. So what would be the $R$-module structure on $\mathrm{End}_{k}(V \oplus V)$?   For the second, I used the fact that $V = k^{\oplus \mathbb N}$ implies $V \cong V \oplus V$ which in turn implies $R = \mathrm{End}_{k}(V) \cong \mathrm{End}_{k}(V \oplus V)$. Again, I just realized that I only showed the latter two are isomorphic as groups.   It may be obvious (and maybe why my professor let it pass?) but I can't come up with a good $R$-module structure that makes the two group isomorphisms $R$-linear.  Edit:  Explicitly, these are the isomorphisms I'm dealing with. Let $\pi_j, i_j$ be the natural projection/inclusion maps of the $j$-th factor resp. and $\psi: k^{\oplus \mathbb N} \oplus k^{\oplus \mathbb N} \to k^{\oplus \mathbb N}$ the isomorphism given by $\psi(e_i, 0)=e_{2i-1}$ and $\psi(0, e_i)=e_{2i}$.  Then the first isomorphism $\mathrm{End}_k(V \oplus V)\to R^4$ is given by $\varphi \mapsto (\pi_1\varphi i_1,\pi_2\varphi i_1,\pi_1\varphi i_2,\pi_2\varphi i_2)$  The second isomorphism $R \to \mathrm{End}_k(V \oplus V)$ is given by $\alpha \mapsto \psi^{-1} \alpha \psi$  The composition doesn't seem to be $R$-linear if I use the obvious $R$-module structure on $R$ and $R^4$. How to block specific websites without using Parental Controls? Why is the Fisher Information matrix positive semidefinite? In the double-slit experiment of electrons (observed by photons), is it correct to say the collapse is caused by the momentum of the photons? I'm working off the article, . I think it's well-written, but I'm not convinced about this part:     So what is causing the change in the particle’s behaviour?      In the example given above, when electrons are fired at a fluorescent screen, when we bombard the electrons with photons the interaction changes the state of the system catastrophically as, despite lacking mass, photons do carry momentum.   Here the author strongly implicates the momentum of photons as being responsible for the collapse. But is that correct to say?  I have read that the  verified that obscuring which-way information restores wave-like behavior. So it feels to me it's more about some "outer" state (perhaps well-characterized as "information") that we don't yet understand that collapses the system, not per se the photon-electron interaction.  Or am I wrong, and in fact for example, the process of obscuring in the quantum eraser experiments somehow "undoes" the photon-electron interaction or restores the quantum state through another interaction? In unix server grep -r option is not working. OS is HP-UX.  If grep -r is not working any alternative way to do recursive search without -r option? Is it possible to load a TikZ library locally? I've done numerous WP sites, written my own plugins, run my own server, etc etc.  But I have not seen this before. I just installed a fresh 4.7.1 and installed the  and all its plugins.  When I went to add media files, I got:  Maximum upload file size: 2 KB.   I deactivated all plugins one by one...no dice. My PHP memory limit is set to 256MB for this installation via wp_config.php.  Googling the 2 KB limit turned up no results.   Anyone seen this before or know how to fix this limit?