Why do File Explorer and Disk Management show different amounts of free space, and how to resolve the discrepancy?
How can I visualize the file system usage on Windows?
What is the best method of re-rendering a web page on orientation change? Potential difference across a zero resistance wire I tried the following code to replace QQ with ZZ, but it doesn't do what I want:  var1=QQ sed -i 's/$var1/ZZ/g' $file   However, this code does what I want:  sed -i 's/QQ/ZZ/g' $file   How do I use variables in sed? Why is everybody so concerned about etc/passwd? Working in Cycles.  Say I have a "disco ball" with a glossy shader. I'm pointing a spot light to it, and I'm trying to have the reflections of that light illuminate the diffuse material on the walls with the patterns from the ball.    I get this:    but I'd like to get something like:    For the illustration I placed a point light inside the ball an removed faces. But what I'd like to do is move the light around the ball so that the light reflected from it changes like it would do in real life.   Is that possible at this point?  EDIT:  Just for the record here's the image rendered in LuxRender (yet another program to learn...) Why can't I use Stack Exchange if I'm under 13 years old, or if I'm under 16 years old and from the EU? I have a map of a city and a .csv-file containing 700 geographic coordinates pointing to locations within that city.  How can I plot these 700 locations on the map? Converting Raw HTTP Request into HTTPWebRequest Object Browse for Servers does not display local instance I just installed SQL Server and SQL Server Management Studio but it doesn't show anything in servers list and I don't know how to connect to it.  This shows that I have installed SQL Server:        But in this image you can see that my Browse for Servers dialog is empty:        Network servers is empty too. I refer to , which I understand says that the branch points of a nonconstant holomorphic map $F: X \to Y$ between Riemann surfaces $X$ and $Y$, both of which are not necessarily compact, form a discrete subset of range $Y$ of the map $F$. (Not sure if 'connected' is part of the definition of Riemann surfaces in other textbooks, but it is here.) Question 1: Do I understand correctly, and is this indeed true? What else I understand:  $A$ is a discrete subspace/subset (I just assume everything here is the usual subspace topology) of $B$ if and only if every singleton subset of $A$ is open in $A$ if and only if every point of $A$ is isolated.  This overflow question () seems to suggest this is not true but is true if $F$ is proper. However, I'm not sure the definitions of Riemann surface are the same (maybe some answers use definitions where Riemann surfaces are not necessarily connected or something).  2.1. I know $F$ is 'discrete' (meaning that its fibres are discrete; here, i refer to a ): see definition before Lemma 3.1, on p. 7), by Proposition II.3.12, and open, by open mapping theorem, which is Proposition II.3.8, but I'm not sure these help show $F$ is proper or are otherwise helpful. Ostensibly 'discrete' maps don't map discrete subsets to discrete subsets.   This stackexchange question () seems to suggest this is true.  I think this is true if $F$ is injective or at least something like locally injective. (Please don't make me type up all the stuff I did for this part.) However based on the question in (3) and based on the , which I think uses the term 'branch points' to mean the same thing as what Miranda means by 'ramification points' (and thus is different from Miranda's 'branch points'), it seems that no neighbourhood $U$ of a ramification point $p \in U \subseteq X$ of $F$ is such that the restriction $F|_U$ is injective.  Kinda related:    This page () says    Now, the ramification and branch points must form a discrete set  I don't think the page assumes anything like $F$ is proper.  The  text in (2.1) actually seems to assume proper based on the '3.7. Proper holomorphic maps' part, but said part refers to 'Lemma 3.17', so I think proper can be replaced with closed. Maybe $F$ is closed or something.  Kinda related (see Question 2 below):     says    If $F$ is proper then the image $\Delta = F(R)$ is discrete in $Y$.   This seems to have all the same assumptions as with Miranda. Ostensibly, either Miranda is wrong or there's some higher level machinery that allows us to omit $F$ proper.  Question 2: To possibly generalise this, what are the minimum requirements on $F, X$ and $Y$ to make $F$ map discrete subsets to discrete subsets? I mean, I'm not sure we really need 'holomorphic' here. I have a feeling this applies perhaps to maps that are just open/closed, continuous and discrete and spaces that are just Hausdorff and locally compact or something.  (again) Kinda related: Well the question is to solve for $x$ in $$a^x+b^x=c \tag{a,b,c are constants}$$   Well as of me, I tried to put $\ln{}$ on both sides which does not seem to help. Apart from this I don't seem to have any other way to solve it.   I turned to WolframAlpha and the solution which was given was : $$x=\dfrac{-i(2\pi n +\pi)}{\ln{a}-\ln{b}} , {n \in \mathbb{Z}}$$  And if $n=0$ $$x=\dfrac{-i\pi}{\ln{a}-\ln{b}}$$  The only thing I am able to recognize is $e^{i\pi}=1$ ... i guess is used.  Link :   So I see that $x$ is independent of the constant $c$.  So how to solve it? Please help...Thanks!    EDIT - It seems that WolframAlpha is taking $c=0$ as suggested by Donkey_2009. And when i write "Solve for x in a^x + b^x = k" it is not returning anything. So are you guys aware of a method to solve this? Also are you guys aware of any other website/software like WA?    P.S. - Also I see that IF we know the values of $a,b,c$ resulting in something like $2^x+3^x=100$ , then Newton's method is the only method I am aware of that can solve it...  Any other suggestions? Remove sudo privileges from a user (without deleting the user) Is there a comma needed before quotation? Is there an English term for "L'esprit de l'escalier"? I have 1-band GeoTIFF file. The color interpretation for band is gray. I want a color table in order to transform my Col.tiff to Col.jpeg or Col.png.  I tried putting a color table in this tiff via a .vrt:  gdal_translate -of VRT  Col.tiff Col.vrt   then adding in the .vrt:  &lt;ColorInterp&gt;Palette&lt;/ColorInterp&gt; &lt;ColorTable&gt;    &lt;Entry c1="0" c2="0" c3="255" c4="240"/&gt;    &lt;Entry c1="0" c2="0" c3="254" c4="240"/&gt;    &lt;Entry c1="0" c2="0" c3="253" c4="240"/&gt;    &lt;Entry c1="0" c2="0" c3="252" c4="240"/&gt; &lt;/ColorTable&gt;   And translate again :  gdal_translate Col.vrt Col.tiff   But it answered:  Warning 1: Unable to export color table to GeoTIFF file.  Color tables can only be written to 1 band or 2 bands Byte or UInt16 GeoTIFF files.   How can I do it?  For information, there is gdalinfo for the Band:  Band 1 Block=55x18 Type=Float64, ColorInterp=Gray   Description = Something   Metadata:     GRIB_COMMENT=Something[p]     GRIB_ELEMENT=TMP     GRIB_FORECAST_SECONDS=0 sec     GRIB_REF_TIME=1401926400 sec UTC     GRIB_SHORT_NAME=SMTHG     GRIB_UNIT=[p]     GRIB_VALID_TIME=1401926400 sec UTC Why are high white balance temperatures redder when warmer objects are bluer? I know it's dumb to ask this type of questions. But, I still don't get this. I've read the "Black body" story and know that when it's heated, it gives off colors; 'warm' colors (red→orange→yellow..) that have low color temperatures, at low temperatures, (I mean, when it is cooler than afterwards) right? And, the black body gives off 'cold' colors (white→blue..) that have high color temperatures at high temperatures (when it is hotter than before), right? Correct? So there're two, yes, very dumb, questions and the latter one is dumber..     Why are that 'warm' colors said to have low temperatures? And 'cold' colors vice versa? So the redder colors have lower c/t and bluer colors have higher c/t, then   why does the camera's color temperature - adjusting slider has the bluer colors on the left, and the redders on the right?       Please, forgive me for my ignorance... A particle experiences an acceleration described by  $$ a=kx^{-2} $$ where x is the displacement from the origin and k is an arbitrary constant.  To what value does the velocity v of the particle converge to as x approaches infinity if the particle starts at some point x0?  If I approach this problem with energy, then $$ W = \int F \mathrm{d}x $$ $$  = \int_{x_0}^\infty mkx^{-2} \mathrm{d}x $$ $$  = mk(-\infty^{-1}+{x_0}^{-1}) $$ $$ W = K = mk{x_0}^{-1} $$ $$ \frac{1}{2}mv^2 = mk{x_0}^{-1} $$ $$ v = \sqrt{2k{x_0}^{-1}} $$  How would I solve this problem with pure kinematics? (there appears to be some sort of cyclical dependency where acceleration affects velocity, velocity affects displacement, and displacement affects acceleration)  Likewise, two particles experience accelerations described by $$ a_1=k_1x^{-2} $$ $$and $$ $$ a_2=-k_2x^{-2} $$ where x is the distance between the two particles  What two velocities do the particles reach as x approaches infinity if the two particles are initially separated by some x0? I am looking for a device that can track my location (lat,long) and speed all day long. Perhaps, I need GPS and accelerometer data bundled together.  What I want to do is to log my daily activities. I spend time walking, running, driving, taking a bus, staying in a building, etc., just like any normal human-being :) I am willing to carry the device with me at all times and would like to see every place I go into and my speed at certain positions.  My requirements are that the location and speed data should be recorded at least every ~20 seconds. I would also like the device to timestamp (date+time) each record. It would be enough if timestamp is precise to nearest minute and the location can go off about a maximum of 10-15m. (30-50ft.)  What I want is a portable device so I can carry all day long for about 2-3 months. I will only use it during casual, daily activities.  I don't want real-time tracking. I can collect the data from a storage later on. I can't remember the gender of the main character.  I remember bits and pieces from different books, but I think they're all part of the same series. The pieces may not be in order or from multiple books.   Boy somehow ends up in a mirror universe that's darker and seems to have no people. He has to travel to a certain office(?) building and steal a book. I think this is towards the end of the book (I can't remember the events leading up to it). I think he finds the portal in a forest or something behind his school. He goes into the ocean with mermaids or something and has to save the ocean from pollution. Aliens exist and are observing Earth, because they think it's undeveloped and are waiting for them to be advanced enough. His mother ends up in hospital and he does something to save her. He goes to Ireland(?) and enters a mountain or something to find a race of people. I can't remember who showed him how, but I'm pretty sure she used magic. He goes to Mars and saves a race from war with themselves(?). This place was hidden inside an illusion. He's also grouped with a linguist that learned their language. He travels to another world where there's a prince. I can't remember, but I think it might've been part of a tournament. His sister goes to a robot planet through a portal. I think the actual planet was a robot/AI and had lots of little robots on it. Can't remember what happens here, but he goes there and saves her from something.   It was set a few years ago, when computers weren't common (his family got one early in the first book, I think).  Thanks in advance if someone finds it. Objective-C Blocks and variable scope