Following . I have just run into . It seems to be fitting perfectly to the Programmers, it is a nearly perfect example of an off-topic question at SO  and yet, it can't be migrated, because it is too old.  How and why came with the idea of questions being to old for migration? What is the reason behind this? If some questions fits badly here and fits perfectly there, what value do we have from blocking their migration only because of their age?  Note: This question is not a duplicate of . I don't want to know, why questions too old for a migration, are migrated even so. I want to know, what is the idea in marking question as too old for migration, at all.
This has come up    : migrating old questions causes problems.   The most popular solution to this to date has been to . This is do-able, but frankly it feels like treating a symptom, and doing so in a way that penalizes folks who answer what are by all appearances valid, on-topic questions.   Migration works best as a way to salvage good but off-topic questions and give them new life on a site where they can thrive. But shuffling old, answered, on-topic questions around for the hell of it is a waste of everyone's time.   Therefore, I think the real solution is much simpler: just disable the migration of old questions. They're rarely welcomed or heavily improved post-migration, often overtly disliked by folks on the destination site, and can end up causing a rather bad experience for folks who were participating in good faith on the original.   I suggest that questions older than 601 days should not be eligible for migration, either by normal user close-votes or by moderators. In extreme cases, we can perhaps provide an alternate means of moving old questions, but under normal circumstances these should be done quickly or not at all.   1 60 days is actually based on a  introduced this past spring: migrated and then rejected questions older than 60 days cause the authors to suddenly gain (permanent) reputation on the destination.
How can I test for a player wearing specific armor? How can I test for a player that is wearing an iron helmet named "test1" and an iron chestplate named "test2" in Minecraft Version 1.12? Blank white desktop icons on new Windows 7 install Consider the vectorspace of all real $m \times n$ vectors and define an    inner product $\langle A,B\rangle = \operatorname{tr}(B^T   A)$.    "tr" stands for "trace"        which is the sum of the diagonal entries of a matrix.   How do you prove that $\operatorname{tr}(B^T   A)$ is indeed a inner product?  Kind regards I have been stuck for several days on this old Analysis problem (I am doing some study on my own).  I have tried several things (which I'll indicate below), but I cannot seem to figure it out.  Here is how the problem is presented: Problem: &quot;Let $f$ be a continuous real-valued function on $[a,b]$.  Suppose there exists a constant $M \geq 0 $ such that $$|f(x)| \leq M \int_a^x |f(t)| dt$$ for all $x \in [a,b]$.  Show that $f(x)=0$ for all $x \in [a,b]$.&quot; My Thoughts: I have tried using the mean value theorem iteratively, but that seems to always lead me down a dead end road.  I deduced that $f(a)=0$.  If only $f$ were assumed to be differentiable, then maybe I could play with trying to get the derivative to be $0$, but unfortunately it's only continuous.  My other thought was to (somehow) use the condition to show that $\int_a^b |f(x)| dx = 0$.  I also played around a bit with contradiction, but to no avail.  Even if one of these hair-brained thoughts is correct, I am not really sure what to do next. If you have any ideas, suggestions, or solutions, I would really appreciate it if you are willing to share them.  Thank you for your time. no space left in '/' but a lot space left in '/home' i install ubuntu and followed a guide to put 20gb in '/' and the rest (150gb) in '/home'. Now i just found out that a lot of the things installed in ubuntu usually goes to '/' instead of '/home'. I have a lot more things to install.  So what is the point of '/home' ? How do I fix this ? Should I transfer 150gb from '/home' to / ?  Filesystem      Size  Used Avail Use% Mounted on udev            7.8G     0  7.8G   0% /dev tmpfs           1.6G  9.5M  1.6G   1% /run /dev/sda6        19G   16G  1.8G  91% / tmpfs           7.8G  676K  7.8G   1% /dev/shm tmpfs           5.0M  4.0K  5.0M   1% /run/lock tmpfs           7.8G     0  7.8G   0% /sys/fs/cgroup /dev/sda2        96M   29M   68M  31% /boot/efi /dev/sda8       159G  1.1G  150G   1% /home tmpfs           1.6G   56K  1.6G   1% /run/user/1000   what is /boot ? Its not '/' or '/home' I'm reading page number 4 here. In particular the section where it deals with the case $p=\infty$, that is , showing that $L^{\infty}$ is complete.    Two questions:  1) Why is the convergence uniform? where it says "for $x \in N^{c}$ , $f_{n}$ is a Cauchy sequence of complex numbers. Thus $f_{n} \rightarrow f$ uniformly. Clearly we have pointwise convergence but why is it uniform?  2) I don't see why $||f_{n} - f||_{\infty} \rightarrow 0$. Can you please explain this step?  Thanks.  (3/2015) Edit: The original link appears to be broken.  seems to provide a similar (maybe even identical) proof to the one the OP talks about with slight notational differences. How do I find out which version and derivative of Ubuntu is right for my hardware in terms of minimal system requirements? For a given hardware configuration, how do I find out if Ubuntu will run on it? What considerations should I take into account when choosing an Ubuntu version and  such as:    with a lighter desktop than the usual Gnome and Unity  with the even lighter LXDE desktop   Obviously Ubuntu does not run on some processor architectures. So how do I go about choosing the right version and derivate. How can I find out the minmal system requirements? The identification of an electron as a particle and the positron as an antiparticle is a matter of convention. We see lots of electrons around us so they become the normal particle and the rare and unusual positrons become the .  My question is, when you have made the choice of the electron and positron as particle and anti-particle does this automatically identify every other particle (every other fermion?) as normal or anti?  For example the proton is a particle, or rather the quarks inside are. By considering the interactions of an electron with a quark inside a proton can we find something, e.g. a conserved quantity, that naturally identifies that quark as a particle rather than an antiparticle? Or do we also just have to extend our convention so say that a proton is a particle rather than an antiparticle? To complete the family I guess the same question would apply to the neutrinos. How to calculate Area Under the Curve (AUC), or the c-statistic, by hand Prove that if 51 positive integers between 1 and 100 are chosen, then one of them must divide another. Given $51$ integers $a_1, a_2, \ldots, a_{51}$ satisfying $1 \leq a_i \leq 100$. Prove that there exist $i$ and $j$ such that $a_i \mid a_j$.   I'm a little unsure how to approach this problem. Thanks for any help. the dinner vs. dinner (grammar question) From the sitcom  (episode ):     KRAMER: (scanning a menu) So, how was the dinner last night?   JERRY: Oh, well…   KRAMER: Did you enjoy the duck? (Elaine comes over…) Oh, Elaine! I was just   asking how dinner went last night.   ELAINE: (sitting down) Oh, well…   KRAMER: Alright, what did you do to Poppie?   ELAINE: Nothing.   KRAMER: Well, he's in the hospital. And the cook says you put him there.   ELAINE: What's wrong with him?   KRAMER: I don't know. I'm gonna go and visit him later. It would be nice if   you got him something. (Punches the table to accentuate this and leaves.)   JERRY: We should get him something.   ELAINE: Yeah. You're right.   I don't understand why Kramer first says the dinner, but when he says it a second time, he drops the article. What's the reason behind that? SQlite: select into? Create violine plots I use pgfplots for most of my plots. Now I need to add a . Is this possible with pgfplots or any other package? What is the proof that the total number of subsets of a set is $2^n$? Riddle (simple arithmetic problem/illusion) I'm not sure how well known this "riddle" is but here it goes.  3 people go to a restaurant, each buy food worth 10.00.  When they're done, they give 30.00 to the waitress.  She gives the money to the manager, manager says they paid too much, gives 5.00 back to the waitress.  She comes back to the table, gives a dollar back to each person and then puts the remaining 2.00 in her pocket for tip.  So now, each person has paid 9.00.  9.00 x 3 = 27.00.  Plus the 2.00 in the waitresses pocket is 29.00.  What happened to the 30th dollar?  So what's the issue with this way of calculating (since if you backward it works fine), that doesn't give us the correct result? How can I identify what application is using a given file? I'm trying to delete some folder but this error is preventing from doing it:     Cannot delete [FileName]: It is being used by another person or program.      Close any programs that might be using the file and try again.   How can I identify what application is using the file?   I want to end the application using a Task Manager, but I didn't know what application is using it.  The folder is not shared and my user account is an administrator. IBM Slack links broken Does anyone know where I can find working Slack invite links to any of IBM's Slack pages? The Slack links on  are all broken. Thank you. The problem   I have tens of thousands of small polygons for which I want to create buffer/doughnuts for, but I don’t get the units right. I want meters and not degrees, and changing to (what I think is) the right CRS my layer doesn’t longer show. The polygons are small farming plots. I work in QGIS 3.4.15.   Let me take you through it  I start by adding a vector layer. I opt for ‘Directory’ as a source type (Encoding: UTF-8 by default) and under Source (Type: UK. NTF2 by default) I point to the folder in which I store the shapefile.   The default CRS is set to EPSG:4326 – WGS 84, for both layer and the project (checked in bottom right), and unit is thus in degrees. I add the layer world map (EPSG:4326 – WGS 84 by default) by taping “world” in the coordinate box in the middle bottom, I also add Open street map (EPSG:3857 – WGS 84 / Pseudo-Mercator by default) from XYZ Tiles. The polygons appear nicely on the map considering some are just adjacent to the nearby lake, many nicely adjacent to roads, etc.   When attempting to do buffers the distance is obviously set to degrees. I have tried to change the CRS, both for the layer(s) and the projects, but without luck. After researching (e.g. here: ) I believe that the correct CSR would be Arc 1960 / UTM zone 36S EPSG:21036 (it is my understanding that either 36N or 36S would work as the polygons appear both south and north of, but close enough to the equator). When setting the mentioned CRS for my polygon layer, the polygons disappear from the map, and remain gone even after setting the project CSR (by bottom right) to the same. It seems that whenever I try with different CRS in UTM, the layer doesn’t show. Does this mean that the polygons are somehow not compatible with units in meter? Is there an issue with importing the .prj file?  Other things I've tried:   I have made a good attempt searching for solutions. I have ensured that the polygon layer is on top of the layers list. I have ensured the file names are identical and tried all different suitable CRS I can think of. I have seen similar questions been solved by saving the .shp 'as', but I don't think that's my issue as it's already a .shp file. Can it be the case that I need to perform a datum transformation? I gave it a shot using a transformation code (1122) provided by above link, but then the polygons were projected on the Antarctica on the world map, so obviously something went quite wrong...   Note that when I have changed to what I believe is the right CRS I can execute buffers in units of meters, however, they do not appear on the window… How do I change the extension of multiple files? Why won't attribute modifiers add up on my armor?