My lenovo A1000 tablet runs the ARM cortex A9 processor based on the ARMv7 architecture,can i install ubuntu touch on it?
With the announcement of the Ubuntu Phone OS I'd like to know what phone (and tablet) models are supported at this time.  Note from foss &amp; Oli: We are making this the master question for all future "Will this work on &lt;insert random tablet/phone/device here&gt;?!" questions
Statements equivalent to the Axiom of Choice The Axiom of Choice reads:     The product of a collection of non-empty sets is non-empty.   As you know well, this axiom is equivalent to many other statements. A few examples (probably the most known) are the following:   Zorn's lemma: Let $(P,\ge)$ be a poset in which every chain has an upper bound. Then $P$ has a maximal element.   This is used in a number of different places to prove very powerful theorems. A couple of examples I can think of right now are: the proof that every ring has a maximal ideal (commutative algebra) and the  (functional analysis).   Well ordering theorem: Every set can be well-ordered (i.e. it admits a total order such that every subset has a least element). Tychonoff's theorem: Every product of compact topological spaces is compact.   This is used for example in the proof of  (again functional analysis).   gives various more. Among them:   Tarski's theorem: If $A$ is an infinite set, then there is a bijection $A\to A\times A$.   (As @Wicht dutifully commented, Tarski's theorem is the name given to the implication $|A|=A\times A \Rightarrow$ Axiom of Choice, while the other implication was known before the proof of this fact by Tarski.)   Every vector space has a basis.   My question is: what are other useful statements which are equivalent to the axiom of choice? Where are they used, and to prove what?  P.s.: By "useful statements" I mean either statements which are important theorems by themselves (as Tychonoff's theorem) or that are directly used in (simple versions of) the proof of important theorems (as Zorn's lemma). Search functionality in lightning:datatable? Is there a way to search across all rows/columns in a lightning:datatable to narrow down the list, just like jQuery DataTables? If so, how do implement that?  Can I somehow do it all on the client-side to make it super fast (some sort of DOM manipulation)  I'm having some issues with the lightning:datatable not updating. I have attached my code below, maybe you can help me spot the issue:  Markup:  &lt;aura:component extends="c:Base" controller="AccountBrowserForm"&gt; &lt;aura:handler name="init" value="{! this }" action="{! c.doInit }"/&gt; &lt;aura:attribute name="selectedAccountId" type="Id" access="public" /&gt; &lt;aura:attribute name="accounts" type="Object"/&gt; &lt;aura:attribute name="mycolumns" type="List"/&gt; &lt;aura:attribute name="sortedBy" type="String" /&gt; &lt;aura:attribute name="sortedDirection" type="Boolean" default="true" /&gt;  &lt;aura:registerEvent name="AccountFilterChange" type="c:AccountFilterChange" /&gt;  &lt;aura:attribute name="backingdata" type="List" /&gt; &lt;aura:attribute name="filter" type="String" /&gt; &lt;lightning:input type="text" onchange="{!c.filter}" value="{!v.filter}" label="Filter" /&gt;  &lt;lightning:datatable aura:id="lightningTable"                      data="{! v.accounts }"                      columns="{! v.mycolumns }"                      keyField="Id"                      onrowaction="{! c.handleRowAction }"                      onsort="{!c.updateColumnSorting}"                      sortedBy="{!v.sortedBy}"                      sortedDirection="{!v.sortedDirection}"                      hideCheckboxColumn="true" /&gt;     Controller:  doInit: function (component, event, helper) {     helper.callServer(component, "c.getAccounts", $A.getCallback(function (response) {         component.set("v.accounts", response);         component.set("v.backingdata", response);         console.log(component.get("v.backingdata") + " /// BACKING DATA INSIDE ")         console.log(component.get("v.accounts") + " // ACCOUTN DATA INSIDE")          component.set('v.mycolumns', [{                 type: "button",                 typeAttributes: {                     label: '',                     iconName: 'utility:add',                     name: 'selectRecord',                     title: 'selectRecord',                     disabled: false,                     value: 'edit',                     variant: {                         fieldName: 'variantValue'                     },                 }             },             {label: 'Name', fieldName: 'Name', type: 'text', sortable: true},             {label: 'Street', fieldName: 'BillingStreet', type: 'text', sortable: true},             {label: 'Postal Code', fieldName: 'BillingPostalCode', type: 'text', sortable: true},             {label: 'City', fieldName: 'BillingCity', type: 'text', sortable: true},             {label: 'Country', fieldName: 'BillingCountry', type: 'text', sortable: true},         ]);          console.log(component.get("v.backingdata") + " *** BACKING DATA OUTSIDE *** ")         console.log(component.get("v.accounts") + " *** ACCOUNT DATA OUTSIDE *** ")     })) },  filter: function (component, event, helper) {     var data = component.get("v.backingdata"),         term = component.get("v.filter"),         results = data,         regex;     try {         regex = new RegExp(term, "i");         // filter checks each row, constructs new array where function returns true         results = data.filter(row =&gt; regex.test(row.name) || regex.test(row.age.toString()));     } catch (e) {         // invalid regex, use full list     }     component.set("v.accounts", results); },   For some reason the filter function is completely unresponsive. Also, does it matter that I'm populating the component with a response from a callback function. @sfdcfox, I noticed in your example that you simple created an array with dummy data. My "myaccounts" attribute is of type object The most efficient method to obtain the total entries into a mysql table "I have never said" versus "I never said" Compact way to assign values by slicing list in Python Can the Flash do things like build muscle faster than normal (do his muscles grow right after a work-out or meal)? Can he heal faster than normal? Does he have a faster immune system to stop all illness or at least make the flu last 2 minutes or something along those lines? Real analysis derivate problem. How can I prove this? Let $f$ be differentiable in $[a,b]$ and $f(a)=0$. If $\exists M \in R$ such that $\vert f'(x) \vert \leq M \vert f(x)\vert \ $,  $\forall x \in [a,b]$, then $f(x)=0, \ \forall x \in [a,b]$.  $\\$ I have an idea, but I can´t see it clear. I have arrived to the inequality $\vert f(x)\vert \leq  K\vert f(y)\vert $ for $y \in (a,x)$, supposing $k&gt;0$ and repeating the process $\vert f(x)\vert \leq  K^n\vert f(z)\vert$ for $a&lt;z&lt;y&lt;x$. If $K&lt;1$, then if $n \rightarrow \infty \ $, $f(x)=0$. That´s a sort of intuitive idea. Primary key or Unique index? At work we have a big database with unique indexes instead of primary keys and all works fine.  I'm designing new database for a new project and I have a dilemma:  In DB theory, primary key is fundamental element, that's OK, but in REAL projects what are advantages and disadvantages of both?  What do you use in projects?  EDIT: ...and what about primary keys and replication on MS SQL server? Since Ubuntu 18.04 I can't drag a file e.g. image file to an open application such as Inkscape or  email message window. In Ubuntu 17.10 I was able to select the image file by clicking on it, and while holding down left mouse button I would hit the supper key displaying all open windows where for there I could then drop the file in any open app or folders. This is no longer possible/default behaviour since Ubuntu 18.04. Is there a workaround that would allow me to achieve this or even a way to recreate the same behaviour like in 17.10? error: file '/grub/i386-pc/normal.mod' not found. grub rescue&gt;   What can I do? I just sit and stare at it.   I found my old netbook (Dell Inspiron 1010) which I have not used for about four years. I replaced Windows XP with Ubuntu 12.10. I used my bootable USB drive. I installed and rebooted. I got the message that normal.mod is not found.   What should I do? Type exit, reboot, or quit? Should I re-install? My husband is a teacher in New Jersey; 61 years of age. He has a pension plan listed on w-2 in box 14 (other). It is coded as 414(h). He asked the tax advise person at the school if he could still contribute maximum yearly amount to an individual Ira and was told yes. An accountant we know told us this was incorrect. Can he deduct the amount placed in individual Ira? I have this on the command line:    ln -sf $PWD/wine-   and then I hit Tab to complete the filename.  In earlier versions of Ubuntu, this worked just fine to complete the wine- filename (and as a side-effect $PWD would be expanded at that time).  But now it turns it in to  ln -sf \$PWD/wine-   which isn't what I meant at all and doesn't complete anything as the file does not literally start with $.  How do I get completion back to the less broken behaviour?  set tells me these are my current settings:  BASHOPTS=checkwinsize:cmdhist:expand_aliases:extquote:force_fignore:hostcomplete:interactive_comments:progcomp:promptvars:sourcepath SHELLOPTS=braceexpand:emacs:hashall:histexpand:history:interactive-comments:monitor Probability distribution in the coupon collector's problem I'm trying to solve the well known Coupon Collector's Problem by explicitly finding the probability distribution (so far all the methods I read involve using some sort of trick). However, I'm not having much luck getting anywhere as combinatorics is not something I'm particularly good at.   The Coupon Collector's Problem is stated as:  There are $m$ different kinds of coupons to be collected from boxes. Assuming each type of coupon is equally likely to be found per box, what's the expected amount of boxes one has to buy to collect all types of coupons?  What I'm attempting:  Let $N$ be the random variable associated with the number of boxes one has to buy to find all coupons. Then $P(N=n)=\frac{|A_n|}{|\Omega _n|}$, where $A_n$ is the set of all outcomes such that all types of coupons are observed in $n$ buys, and $\Omega _n$ is the set of all the possible outcomes in $n$ buys. I think $|\Omega _n| = m^n$, but I'm not even sure about that anymore, as all my attempts so far led to garbage probabilities that either diverged or didn't sum up to 1. How to change the disk space left warning in Windows 7? my disk has over 100GB of free space, but the usage bar in Computer is displayed in red, as if it reached a low space limit. It looks like Windows applies the same 10% or 15% hard disk space value for low space warnings, regardless of if the disk is 50GB in size or 1.5TB, which is not very smart and obsolete for most recent computers.  Is there a Registry key or some place I can change this percentage so the usage bar displays in green, not red?  The hibernation and page files are already reserved (5GB together), so surely the low space warning for a 1.5TB disk should be 5-10GB, not 150GB or more. The way Windows 7 computes the low space limit seems pretty dumb, not much Intellisense there.  This is not a high priority issue, but it makes the Computer applet look pretty stupid and it's irritating every day to see that 100GB of free space is putting my computer in the red. It would also be nice to be able to edit this low limit percentage in Computer/Manage/Storage/Disk Management or directly in the disk properties ("Tools" tab). Error message "sudo: unable to resolve host (none)" When I run sudo the terminal is stuck for a few seconds and then outputs an error message. My terminal looks like this:  ubuntu@(none):~$ sudo true sudo: unable to resolve host (none)   What can I do to solve it? Is there a place where I can look what updates I've installed? Mod of numbers with large exponents [modular order reduction] I've read about Fermat's little theorem and generally how congruence works. But I can't figure out how to work out these two:   $13^{100} \bmod 7$ $7^{100} \bmod 13$   I've also heard of this formula:  $$a \equiv b\pmod n \Rightarrow a^k \equiv b^k \pmod n $$  But I don't see how exactly to use that here, because from $13^1 \bmod 7$ I get 6, and $13^2 \bmod 7$ is 1. I'm unclear as to which one to raise to the kth power here (I'm assuming k = 100?)  Any hints or pointers in the right direction would be great. How to change from German to English in the File Manager in Ubuntu 15.10? My months and days in my File Manager are in German, how do I change that? On the photo you see 'Dez' : It means Dezember (German for December). I also saw one day Mittwoch (German for Wednesday). How do I change that German issue? This is only my File Manager and not completly but partially. Weird. Has anyone successfully embedded their  on a WordPress.com-hosted blog?  The free hosted version of  (not )  from all posts before publishing. So they to strip out just about anything I can add to embed my Stack Overflow flair.  Note: I'll be switching to a paid, hosted site in the future (fixing the problem), but I'm looking for a quick, short-term solution. Connecting two Ethernet PHY without magnetics? In a (tentative) new design I want to connect two 100 Mbit/s Ethernet PHY similar to , separated by few inches on the same PCB, with same ground plane (but different power supplies). I have the choice of one of my PHY, but the other is embedded in an as-yet-unspecified PCIe to Ethernet IC (perhaps Gigabit but used in 100 Mbit/s mode), and it is critical that this PHY thinks there is a bona fide 100 Mbit/s Ethernet connection.  I could use the following         &ndash; Schematic created using   but I would like to achieve the same without the magnetics, in order to save on cost, purchasing headaches, and if at all possible power consumption.  I can imagine an RC network, perhaps as simple as in this , found thanks to a ; or maybe engineered with attenuation and lowpass, but that will not emulate the fact that with real magnetics, when there is a negative pulse on TX1P, there is a positive pulse on TX1M and RX2M. I am uncertain about if that would prevent some PHYs from working normally.  Anything to suggest that one is confident will work for practically any PHY around?