I'm trying to write something like this: \begin{itemize} \item \(x^2+y^2-1=0; \quad\quad\quad\) (ellipse) \item \(x^2-y^2-1=0; \quad\quad\quad\) (hyperbola) \item \(x^2-y=0; \quad\quad\quad\) (parabola) \end{itemize}  I'm struggling to find out how to make it right without using all those \quad and aligning the captions. Thanks in andvance 🥺
I want to describe the variables involved in an equation in an itemized environment such that every item begins with the variable name and subsequently comes the description for it. I'd like to have all the descriptions left aligned.  Here is a MWE that of course does not produce what I am looking for.  \documentclass{standalone} \begin{document} $E[g(x)] = \int_{-\infty}^{+\infty} f_X(x) \, g(x) \, \mathrm{d}x$. % where, % \begin{itemize}     \item $x$      \quad is a continuous random variable.     \item $f_X(x)$ \quad is the PDF of $x$.     \item $g(x)$   \quad is a function of $x$. \end{itemize} \end{document}
If dark matter only interacts with gravity, why doesn't it all clump together in a single point? I'm a complete layperson. As I understand, dark matter theoretically only interacts with the gravitational force, and doesn't interact with the other three fundamental forces: weak nuclear force, strong nuclear force, and electromagnetism.  Those are my understandings going in. If I'm wrong, please correct me. I've done some googling, and I haven't found anything confirming or denying that dark matter is affected by either of the fundamental nuclear forces.  So since dark matter only interacts with gravity, what causes any dark matter particle to be repelled from another? If they can pass freely through each other, and they are gravitationaly attracted to each other, why don't such particles clump together in a single 'point' in space?   It seems to me that particles occupying a single 'space' are philosophically not distinct particles, but I don't know how actual physics would play into this.  Edit , author's credentials unknown, but implicitly claims to be a physicist or astronomer, says "...[P]hysicists generally take all dark matter to be composed of a single type of particle that essentially interacts only through gravity."  Edit 2 The author is this , "Professor of Science on the physics faculty of Harvard University." Sometimes when I'm making a sauce or soup that needs to be a bit spicy, I have no troubles spicing how I want to.  But if the dinner party is a bit late, or I made the sauce in advance to really draw out all the flavors of the spices, vegetables and meat, sometimes I end up with a way too spicy/hot dish.  You can always pour a bit water and try to dilute it a bit, but that also takes away all of the good flavor. So is there some trick that I'm missing I can use, when this happens to me (other than being more careful or using the spices later)? How do I find out which dlls an executable will load? JavaScript open in a new window, not tab I have a select box that calls window.open(url) when an item is selected.  Firefox will open the page in a new tab by default.  However, I would like the page to open in a new window, not a new tab.    How can I accomplish this? "The following" vs. "Following" I wrote      "Following examples show ..."   and my colleague revised it as      "The following examples show ..."   Why do we need "the" here even though the examples have not been mentioned before? FM transmitter design? I stumbled across a relatively simple FM radio transmitter online.    Credit:   I wanted to understand how it works (it is called "super simple" on the website), but several hours I have nothing but a vague understanding.   I believe R2, L1, C3 form an oscillator, and then the transistor Q1 is used to modulate the signal. C1 would just be used to remove any DC offset. However, this leaves R1, C2, C4, C5, and R3 and,  for these components,  I have no clue what they do.   Could someone please explain how this "super simple" transmitter works? Including pdf_tex images from inkscape I have Ubuntu budgie 17.04 (budgie-desktop 10.2.9). While pressing Alt+Tab to switch between the windows, the windows are switched randomly and I am not able to select which window to shift.  This feature was available in Ubuntu 16.04 but not in Ubuntu-budgie-17.04.    How to resolve this? Programmatically obtain the phone number of the Android phone $(\mathbb{R}^n,\|\cdot\|_{p})$ is isometrically isomorphic to $(\mathbb{R}^n,\|\cdot\|_{q})$ iff $p=q,$ Proving inequality $\frac{a}{b}+\frac{b}{c}+\frac{c}{a}+\frac{3\sqrt[3]{abc}}{a+b+c} \geq 4$ I started to study inequalities - I try to solve a lot of inequlites and read interesting .solutions . I have a good pdf, you can view from  . The inequality which I tried to solve and I didn't manage to find a solution can be found in that pdf but I will write here to be more explicitly.  Exercise 1.3.4(a) Let $a,b,c$ be positive real numbers. Prove that $$\displaystyle \frac{a}{b}+\frac{b}{c}+\frac{c}{a}+\frac{3\sqrt[3]{abc}}{a+b+c} \geq 4.$$ (b) For real numbers $a,b,c \gt0$ and $n \leq3$ prove that: $$\displaystyle \frac{a}{b}+\frac{b}{c}+\frac{c}{a}+n\left(\frac{3\sqrt[3]{abc}}{a+b+c} \right)\geq 3+n.$$ How to use measured step response to tune control system How does one use a measured step response to tune either a PID or convolution control scheme? Inspired by , I'm interested a more detailed explanation of how to implement a control system based on the measured step response.  I would not try to guess all the effects.  There are probably some non-obvious things going on, and you can't know all the parameters. I would measure the step response.  Find two pump settings that both result in the ball being within the measurable range within the tube.  Then have the controller suddenly switch from one setting to the other open loop.  Meanwhile measure what the ball does over time.  That is the step response.  You can take the derivative of that and get the impulse response.  From the impulse response you can predict the motion of the ball for any history of pump settings, assuming this is a linear system.  It is probably linear enough over the small range of settings to keep the ball within its normal range. You can use this as a simulation base to find the parameters for old fashioned PID control.  Or you can use the impulse response directly to do a convolution control.  You have to low pass filter the control input enough so that convolution kernel doesn't go negative unless your pump is actually reversible and can suck the ball back down.  How exactly does this work? ; I assume &quot;convolution control&quot; is the use of the pole-zero or transfer function, but don't see exactly how to get the parameters. RELATED:  * How can I randomize order of elements in a list? How can i get my community Base URL in apex I am using  Salesforce Community and I have network Id of the community but I don't know how can I get Base URL of my community. Any one know how can I get my community base URL using its id in apex as a internal user.  Is there any other way in which salesforce internal user can get the base URL of all his community in the apex also i don't find any object in which Community Base URL is stored. I checked network sObject but it only store community path prefix not the complete URL so how can i get the base URL for my community? Finding the limit of $(1-\cos x)/x^2$ The security guard problem pyPdf for IndirectObject extraction Following this example, I can list all elements into a pdf file  import pyPdf pdf = pyPdf.PdfFileReader(open("pdffile.pdf")) list(pdf.pages) # Process all the objects. print pdf.resolvedObjects   now, I need to extract a non-standard object from the pdf file.   My object is the one named MYOBJECT and it is a string.  The piece printed by the python script that concernes me is:  {'/MYOBJECT': IndirectObject(584, 0)}   The pdf file is this:  558 0 obj &lt;&lt;/Contents 583 0 R/CropBox[0 0 595.22 842]/MediaBox[0 0 595.22 842]/Parent 29 0 R/Resources   &lt;&lt;/ColorSpace &lt;&lt;/CS0 563 0 R&gt;&gt;     /ExtGState &lt;&lt;/GS0 568 0 R&gt;&gt;     /Font&lt;&lt;/TT0 559 0 R/TT1 560 0 R/TT2 561 0 R/TT3 562 0 R&gt;&gt;     /ProcSet[/PDF/Text/ImageC]     /Properties&lt;&lt;/MC0&lt;&lt;/MYOBJECT 584 0 R&gt;&gt;/MC1&lt;&lt;/SubKey 582 0 R&gt;&gt; &gt;&gt;     /XObject&lt;&lt;/Im0 578 0 R&gt;&gt;&gt;&gt;   /Rotate 0/StructParents 0/Type/Page&gt;&gt; endobj ... ... ... 584 0 obj &lt;&lt;/Length 8&gt;&gt;stream  1_22_4_1     ---&gt;&gt;&gt;&gt;  this is the string I need to extract from the object  endstream endobj   How can I follow the 584 value in order to refer to my string (under pyPdf of course)?? Is it possible to sync files via rsync and let rsync only compare mtime informations?  Or is there another tool for this job?  That means that such a tool only copies src to destination if the src is newer than the destination. Comparable to GNU cp --update - but also over ssh ... Suddenly unable to screenshot- Do not have permission to save files in the location where screenshots are stored Recieved the error:  'Your screenshot could not be saved. You don't have permission to save files in the location where screenshots are stored.' with OS X Yosemite.  I opened terminal and tried directing the screenshots to save on my desktop:  Brigittes-Air:~ eggsalad$ defaults read com.apple.screencapture location 2017-01-06 03:04:47.765 defaults[17729:1947540]  The domain/default pair of (com.apple.screencapture, location) does not exist  So I tried writing and:  Brigittes-Air:~ eggsalad$ defaults write com.apple.screencapture location ~/Desktop 2017-01-06 03:05:08.652 defaults[17742:1948451] Could not write domain com.apple.screencapture; exiting  I'm not sure where the screenshots are being stored if the location does not exist. Ideas?  EDIT  I ran something else and got a different response, but defaults are still unchanged.   Brigittes-Air:~ eggsalad$ defaults write com.apple.screencapture location/Users/eggsalad/Desktop killall SystemUIServer  2017-01-06 03:22:35.444 defaults[18265:2001767] Unexpected argument SystemUIServer; leaving defaults unchanged.  2nd EDIT  Result of:  ls -l ~/Library/Preferences/com.apple.screencapture.plist  was:   ls: /Users/eggsalad/Library/Preferences/com.apple.screencapture.plist: No such file or directory When can I use a forward declaration?