So I wanted to test ArrayList vs LinkedList remove() method times just for fun.  I wrote code below to do it - everything is pretty self-explanatory: deleteEachNth runs through my list and deletes every nth element it sees.  I was expecting to see LinkedList winning by a huge margin, as its remove times are constant-time operations, but my code produces opposite results: for 10000 elements ArrayList is twice as fast.  Naturally, I thought I'd written something wrong, perhaps used a get(), which would slow LinkedList down somewhere, but it isn't the case.  Whats wrong  here?  EDIT: When replacing System.currentTimeInMillis() with System.nanoTime() LinkedList still performs worse for my code.   import java.util.ArrayList; import java.util.LinkedList; import java.util.List; import java.util.stream.IntStream;  public class Test{     List&lt;String&gt; myList;     Test(List&lt;String&gt; someList){         myList = someList;     }     void eliminateEachNth(int n){         for (int i = 1; i &lt; myList.size(); i++) {             if(i%(n-1)==0){                 myList.remove(i);             }         }     }     public static void main(String[] args){         List&lt;String&gt; someList = new ArrayList&lt;&gt;();         IntStream.range(1, 10000).forEach(i-&gt;someList.add(Integer.toString(i)));         Test testArray = new Test(someList);         long cur = System.currentTimeMillis();         testArray.eliminateEachNth(3);         System.out.println("array list took " + (System.currentTimeMillis() - cur) + "millis");         System.out.println(someList);         List&lt;String&gt; anotherList = new LinkedList&lt;&gt;();         IntStream.range(1, 10000).forEach(i-&gt;anotherList.add(Integer.toString(i)));         Test testLinked = new Test(anotherList);         cur = System.currentTimeMillis();         testLinked.eliminateEachNth(3);         System.out.println("linked list took " + (System.currentTimeMillis() - cur) + "millis");         System.out.println(anotherList);      } }
How do you write (and run) a correct micro-benchmark in Java?  I'm looking for some code samples and comments illustrating various things to think about.  Example: Should the benchmark measure time/iteration or iterations/time, and why?  Related:
Since I can't find any alternative to Linux'  elevation command, I have the following question:  How to define a PowerShell function which requires elevation? I mean UAC prompt.  Say, such function follows:  function system-check {     SFC /ScanNow }   System:  Windows 8.1 Pro 64-bit  PowerShell:   Major  Minor  Build  Revision -----  -----  -----  -------- 5      0      10586  117    EDIT1:  To be 100% understandable let me rephrase:   I run PowerShell as user I run the aforementioned function system-check I want the function to elevate in order to be able to execute the command; note, that I want the UAC prompt to appear df -h - Used space + Avail Free space is less than the Total size of /home As the output of df -h shows here, something is eating up 5GB of free space. So, it's not available to use.   I'm also noticing sometimes that the hard disk gets filled up to 100% sometimes. So, I had to restart the machine or delete some unncessary files. Only noticed these in /home partition. Don't know whether these two are related, but appreciate if anyone can put some insight into this.  $ df -h Filesystem            Size  Used Avail Use% Mounted on /dev/sda8             100G   92G  2.7G  98% /home I am thinking about buying a new lens specifically to take photos of distant targets (birds, bears, etc). I currently own the Canon 70-300 IS USM, which is a nice lens, but I find that if I want to take a photo of anything further away than about 10 meters, the target does not fill a large amount of the frame (meaning I have to significantly crop in post production).  I am currently looking at the Canon prime 400mm, however I would like to determine at what distance an object will fill a reasonable proportion of the frame.  Is there a formula or rule of thumb I can apply that will help me in this situation? I realise the size of the target I am shooting will play a role here, so if we need to make an assumption about the size of the target please let me know. Better yet, are there any Spacewalk-like software packages that work for both RedHat-based and Debian-based systems? The problem of counting the solutions $(a_1,a_2,\ldots,a_n)$ with integer $a_i\geq0$ for $i\in\{1,2,\ldots,n\}$ such that $$a_1+a_2+a_3+....a_n=N$$ can be solved with a stars-and-bars argument. What is the solution if one adds the constraint that $a_i\leq r_i$ for certain integers $r_1,\ldots,r_n$?  e.g. for $n=3$, $N=6$ and $(r_1,r_2,r_3)=(3,3,2)$, the tuple $(a_1,a_2,a_3)=(2,3,1)$ is a solution, but $(2,1,3)$ is not a solution because $a_3=3&gt;2=r_3$. Let $A\neq I$ be a $5\times5$ matrix with real entries such that the sum of the entries in each row of $A$ is $1$. Then the sum of all the entries in $A^3$ is  1)$\space 3$ $\qquad $2)$\space 15$ $\qquad$ 3)$\space 5$ $\qquad$ 4)$\space 125$  Solution:  The answer is $5$ if $A = I$, but for $A \neq I$,  I found that vectors $\begin{pmatrix} 1\\ 1\\ 1\\ 1\\ 1\\ \end{pmatrix}$ and  $\begin{pmatrix} -1\\ -1\\ -1\\ -1\\ -1\\ \end{pmatrix}$  are eigen vectors for the matrix $A$ corresponding to eigen value $1$. From here, I dont know how to proceed, please help me solve the question..and if there are mistakes in my argument, please tell me.. Let $P$ be a prime. Show that $\exists$ $x \in \mathbb{N}$ such that $f(x) = p$ then $\exists$ $y \in \mathbb{N}$ such that $g(y) = p$ What is given?  $$\text{Let P be a prime}$$ $$\text{Let} \space f(x)= 3x+1$$ $$\text{Let} \space g(x)= 6x+1$$  Show that: If there exists $x \in \mathbb{N}$ such that $f(x) = P $ , then there exists a $y \in \mathbb{N}$ , such that $g(y) = P$  What have I tried?   Given the question says 'show that', that leads me to believe I need to do a proof of sorts. I'm guessing it might be a proof by either strong induction, or just induction (or maybe just a direct proof?).  I don't even know how to set this up If $f(x) =$ $3x + 1 = $ prime...for any integer $x$, then there exists an integer $y$ such that $g(y) = 6y + 1 = $ prime?   Any hints or starting points would be greatly appreciated.   $$\text{Thanks in advance!}$$ "What kind of a person" vs. "what kind of person" a, b are integers. p is prime. I want to prove: $(a+b)^{p} \equiv a^p + b^p \pmod p$  I know about Fermat's little theorem, but I still can't get it I know this is valid: $(a+b)^{p} \equiv a+b \pmod p$ but from there I don't know what to do.  Also I thought about $(a+b)^{p} = \sum_{k=0}^{p}\binom{p}{k}a^{k}b^{p-k}=\binom{p}{0}b^{p}+\sum_{k=1}^{p-1} \binom{p}{k} a^{k}b^{p-k}+\binom{p}{p}a^{p}=b^{p}+\sum_{k=1}^{p-1}\binom{p}{k}a^{k}b^{p-k}+a^{p}$ Any ideas?  Thanks! Show $\operatorname{Aut}(C_2 \times C_2)$ is isomorphic to $S_3=D_6$ ASP.NET MVC How to pass JSON object from View to Controller as Parameter I have a complex JSON object which is sent to the View without any issues (as shown below) but I cannot work out how Serialize this data back to a .NET object when it is passed back to the controller through an AJAX call. Details of the various parts are below.     var ObjectA = {         "Name": 1,         "Starting": new Date(1221644506800),          "Timeline": [             {                 "StartTime": new Date(1221644506800),                 "GoesFor": 200              }             ,             {                 "StartTime": new Date(1221644506800),                 "GoesFor": 100              }          ]     };   I am not sure how this object can be passed to a Controller Method, I have this method below where the Timelines object mirrors the above JS object using Properties.  public JsonResult Save(Timelines person)   The jQuery I am using is:          var encoded = $.toJSON(SessionSchedule);          $.ajax({             url: "/Timeline/Save",             type: "POST",             dataType: 'json',             data: encoded,             contentType: "application/json; charset=utf-8",             beforeSend: function() { $("#saveStatus").html("Saving").show(); },             success: function(result) {                 alert(result.Result);                 $("#saveStatus").html(result.Result).show();             }         });   I have seen this question which is similar, but not quite the same as I am not using a forms to manipulate the data.   I have also seen references to using a 'JsonFilter' to manually deserialize the JSON, but was wondering if there is a way to do it nativly though ASP.NET MVC? Or what are the best practices for passing data in this way? How do I remap the keys on my keyboard? I broke my laptop and had to buy a new one with a new keyboard that I am struggling to get familiar with, especially with the keys like home, page-up, page-down and end, which aren't standardized at all.  I found myself doing this for like the 5th time in the last several years, and I think it is really annoying.   Is there an app that can reliably map one key to another?  By reliably I mean that key mapping works with Shift, Alt, and other modifiers.  UPDATE  Windows 7, Samsung Chronos 7 Is it possible to include one CSS file in another? Is it possible to include one CSS file in another? Fetch the row which has the Max value for a column How to run Visual Studio post-build events for debug build only How can I limit my post-build events to running only for one type of build?  I'm using the events to copy DLL files to a local IIS virtual directory, but I don't want this happening on the build server in release mode. Changing Network Interfaces name Ubuntu 16.04 I tried to change network interfaces name on this new Ubuntu 16.04 LTS version but doesn't have the /etc/udev/rules.d/70-persistent-net.rules.  So, I tried to use /lib/udev/write_net_rules but it not exist.  Why do I need this modification? Because I'm using a tool to Simulate virtual platforms that use flex licensing and the authentication need to be in eth0 interface name.  Any suggestion?  The command ip link returns:  user@laptop:~$ ip link  1: lo: &lt;LOOPBACK,UP,LOWER_UP&gt; mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: enp6s0: &lt;NO-CARRIER,BROADCAST,MULTICAST,UP&gt; mtu 1500 qdisc pfifo_fast state DOWN mode DEFAULT group default qlen 1000 link/ether b8:2a:xx:yy:xx:yy brd ff:ff:ff:ff:ff:ff 3: wlp7s0: &lt;BROADCAST,MULTICAST,UP,LOWER_UP&gt; mtu 1500 qdisc mq state UP mode DORMANT group default qlen 1000 link/ether 5c:e0:xx:yy:xx:yy brd ff:ff:ff:ff:ff:ff  user@laptop:~$ ifconfig  enp6s0    Link encap:Ethernet  HWaddr b8:2a:xx:yy:xx:yy   lo        Link encap:Local Loopback   wlp7s0    Link encap:Ethernet  HWaddr 5c:e0:xx:yy:xx:yy     (Some information were ignored and suppressed)  I already tried some links: pass 1 environment variable using sudo How can I tell what year my bike was made? The Unix environment has some excellent tools for parsing text in various forms. However, of late, the data is not in the traditional (historical) formats (CSV, TSV, record-based or some other delimiter-based) it used to be before. Data these days is exchanged in structured formats like XML/JSON.  I know there are some good tools like sed, awk and Perl which can chew down nearly any form of data out there. However, to work with this sort of structured data, often one has to write a complete program, and, given the little time available to extract information, one has to sit down and figure out the whole logic of what one wants to query and put it down programmatically. Sometimes this is not OK – basically because the information extracted from those files acts as inputs for further work; also because of the time it takes to search for the appropriate solution and code it up. A command line tool is needed with sufficient switches to find, query and dump data.  I'm looking for tools that take a XML/JSON or other forms of structured data and dump it into other formats like csv, etc., so that from there one could use other commands to get any information out of it.  Are there any command line utilities you know of which do this kind of a job? Are there already awk/Perl scripts available to this? Whenever I try to do a fluid simulation, the fluid domain remains visible.  I have tried:ctrl+a-scale, turn on/off visibility for render/viewport  Here's a video demonstrating my problem:   Here's the blend file in case I have messed up some settings:   Thank you for any help!