I'm fairly new to learning about computers. I have a self-built computer and while installing Ubuntu (my first operating system) I run into a dialog.   I press install now and it replies      no root file system is defined. Please correct this from the partitioning menu   The partition table button is grayed out and the only thing I can do is press the change button. The change button crashes it so I can't continue and I have no options to press.
I want to install Ubuntu on the C: partition where my Windows 7 is, simply to replace the systems. I've also tried to install it on another partition (without formating it), which failed!  All I get is:      No root file system is defined. Please correct this from the partitioning menu.   I want to install Ubuntu without formatting any of my partitions. Is that possible?
How can brackets be escaped in using string.Format? For example: String val = &quot;1,2,3&quot; String.Format(&quot; foo {{0}}&quot;, val);  This example doesn't throw an exception, but it outputs the string foo {0}. Is there a way to escape the brackets? Prove: if $|z|=1$ than $\frac{z+1}{z-1}$ is an imaginary number Prove: if $|z|=1$ than $\frac{z+1}{z-1}$ is an imaginary number    I have tried to look at $$\frac{z+1}{z-1}=\frac{z+1}{z-1}\cdot \overline{\frac{z-1}{\overline{z-1}}}=\frac{z+1}{z-1}\cdot \frac{\overline{z}-1}{\overline{z}-1}$$  But did not get far Coordinate descent soft-thresholding update operator for LASSO I was reading this paper () describing the coordinate descent algorithm for LASSO, and I can't quite figure out how the soft-thresholding update for each $\beta_j$ is derived for the linear regression case. Specifically, how does one go from equation (4) to equation (5) in the paper? Can anyone show me a detailed derivation of the update? Thanks!  Edit: actually this paper deals with the elastic net penalizing term, which reduces to LASSO when $\alpha=1$. I am mostly interested in LASSO, but I guess the derivation should be principally the same for elastic net. What triggers the benefit of the bard's "Song of Rest" feature? In D&amp;D 5e, the benefit of the Bard's "Song of Rest" feature triggers "if you or any friendly creatures who can hear your performance regain hit points at the end of the the short rest."  Does Song of Rest's benefit apply just when spending hit dice to regain hit points? Or does it apply to any other way that a player might regain hit points at the end of a short rest (e.g. by casting a spell, using a Second Wind, eating a Goodberry, etc.)? Is there an alternative to the word "coincidence" to describe when two say the same word spontaneously? Is there a word to describe a scenario where two people having a conversation utter the same word/phrase together, simultaneously, and unconsciously? Something else than just a coincidence. I'd like to see if somebody has been trying to log-in by brute-force into my Ubuntu 12.04 server over SSH. How can I see if such activities have been taking place? I try to color the page numbers of my table of contents.  I'm using the package hyperref along with the options :  \hypersetup{   colorlinks,   linkcolor=wine-stain % custom color }      Here's the output :       The numbers remain black..  What should I do so the numbers become the same color as defined for the sections ?  I tried to \color{wine-stain}{\tableofcontents} but still that doesn't work since "Contents" is also colorized and the subsection numbers are remaining black. using Ajax with 3 consecutive drop down lists depending on eachother Formatting Ticks and FrameTicks labels with a function How to convert an instance of std::string to lower case What do you call someone who always puts blame on others? I have been thinking about the following formulation of the Axiom of Choice.:     For any relation $R$, there is a function $H$, which is a subset of $R$, and such that $\operatorname{dmn}H=\operatorname{dmn}R$.   At first, it seemed surprising to me that this did not follow from Comprehension (i.e., from the schema  $\forall x_1, x_2, ..., x_n \forall C\exists B \forall x ( x \in B \Leftrightarrow x \in C \land \phi )$, where $B$ does not occur free in $\phi$).    I thought that for any relation, it seems that we should be able to define a subset of it with the same domain meeting a "functional condition".  But when I tried to do this, I couldn't.  However, I felt like I was getting close when I let $B$ be free in $\phi$, i.e., when I let myself say that $w$ is in $R$ and also anything in $H$ meets such and such conditions, where $H$ is the set (function) whose existence I'm trying to prove.    But my understanding is that Choice does not even follow from Naive Comprehension.  So, I wondered if someone could explain the following precisely.   Why does the above formulation of Choice does not follow from regular Comprehension? Why does it not even follow from Naive Comprehension (assuming that it does not)? ContentVersion Content-Type I need to stream a file from Salesforce in our webapplication. To make sure the file is properly opened, I have to set Content-Type header.  How to retrieve the Content-Type (MIME) of a file?  I expect values like: image/png, application/pdf, text/html etc.  How to get these values? I am using the Java and a SOAP client to retrieve the data. I have already proved Triangle Inequality $\lVert v+w\rVert \le \lVert v \rVert+\lVert w \rVert$ in vector space $\mathbb{R}^n$. However, I'm having difficulties proving the Reverse Triangle Inequality in the vector space.  I have started with   $$\lVert v \rVert^2=v \cdot v-w\cdot w+w\cdot w \le \lVert v-w \rVert+\lVert w \rVert^2$$ $$\lVert w \rVert^2=w \cdot w-v\cdot v+v\cdot v \le \lVert w-v \rVert+\lVert v \rVert^2$$  based on the Triangle Inequality but I don't know if it is correct. If this is right, I think I can go on with proving it the same way I would the normal Reverse Triangle Inequality. How to customize title page in beamer so that it looks like How can I modify title page so that it looks like it is in  video. Please seek to 16 seconds and watch title page. I do not have permission to post images. I liked this theme and I want to make a beamer theme that looks similar. I tried with beamercolorbox but I failed to position the box to the bottom.      Edit: Here is my minimum working example  \documentclass[xcolor=dvipsnames]{beamer} \defbeamertemplate*{title page}{customized}[1][] { \usebeamerfont{subtitle} \usebeamercolor[fg]{subtitle}  {\flushright \setbeamercolor{author}{bg=white,fg=Red} \usebeamerfont{author} \insertauthor\par \usebeamerfont{institute}\insertinstitute\par }  \vspace{0.2in}  \setbeamercolor{postit}{fg=white,bg=YellowOrange}  \begin{beamercolorbox}[sep=1em,wd=1.062\textwidth,ht=3cm,dp=3cm,right]{postit} \usebeamerfont{title} {\huge \inserttitle}\par \usebeamerfont{subtitle} {\insertsubtitle} \end{beamercolorbox} } \usecolortheme[named=YellowOrange]{structure} \useoutertheme{infolines} \setbeamertemplate{navigation symbols}{}  \institute{Harvard College Professor and\\ Johnstone Family Professor in Psychology, Harvard University}  \title{SAY WHAT?} \subtitle{Linguistics as a Window to\\ Understanding the Brain} \author{Steven Pinker}  \begin{document} { \setbeamertemplate{footline}{} \begin{frame} \titlepage \end{frame} } \end{document} Bash script to remove the oldest file from from a folder I want to make a bash script to delete the older file form a folder. Every time when I run the script will be deleted only one file, the older one. Can you help me with this? Thanks How do I implement a retro-style password-based "savegame" system? Set "this" variable easily? Feedback for The Loop - May 2020 May’s “The Loop” blog post was just posted, you can read it . A popular response last month to our post about how we receive, prioritize and implement feedback was a question around how this framework gets utilized in the practical sense. We thought that Dark Mode was a great feature to dig down into as it was so widely requested and anticipated.   We hope you enjoy this month’s post, please leave any questions or comments you have in this thread and we will respond ASAP. WordPress twenty eleven sidebar on Pages I am using 2011 theme, any how I managed to get sidebar on single.php pages by installing child theme,  But now I want sidebar on pages,  How do I get it?