How can i debug Hadoop map reduce
How to debug hadoop mapreduce jobs from eclipse?
I'm always wondering: most GNU/Unix tools take options in the form "minus something", sometimes followed by an argument. What if you got a file named minus something?  $ ls -f $ rm -f $ ls -f $ mv -f abc mv: missing destination file operand after `abc' Try `mv --help' for more information. $ cat -f cat: invalid option -- 'f' Try `cat --help' for more information.   or  $ ls -ohello.c $ gcc -ohello -ohello.c gcc: fatal error: no input files compilation terminated.   This is just out of curiosity; I don't have a use case for this. Not to Mention ≈ [Let Alone ≈ Much Less ≈ Still Less] For brevity, I symbolise synonymity with ≈.  So  X ≈ Y  means  X and Y are synonyms.  From : let alone ≈ not to mention  From :  let alone ≈ much less ≈ still less.  Are these all synonyms? What are the similarities and differences between each? I'm trying to install the  IDE in my Ubuntu and in the process it's asking for my root password which I don't remember. I know my  user password. How can I recover my root password? How do I get useful SQL Server database performance statistics? We currently have several shared SQL Server servers and instances in our organization. They are going with a different architecture where business units will get their own SQL Server instances. We have SQL Server 2008R2.  In the past, databases were put on servers in a more or less random fashion -- business use and disk space were the main drivers.  I've been tasked with coming up with a plan for allocating our 50+ databases across 3 servers (one instance per server). My criteria for divvying them up is as follows:   Business critical db's should be spread across the servers. i.e. avoid lumping a bunch of business critical db's all one server.   For the remainder of the non-mission critical db's, consider: a. Disk space usage b. I/O usage -- memory, CPU, etc.     1 and 2a are easy for me to figure out. I know how to get data file sizes.   My question is with that last bit - 2b. I do not know how relevant this is, what specific stats to look at, or how to get them.   Frankly, I'm not 100% sure how to phrase this question! I think I basically want to know is, "How 'busy' is this db -- however you define 'busy'?" Or maybe, "How does this db impact the performance of the server?"  I mean, disk space is important -- but it could (in theory) have a ton of rows or binary objects in there that are not written very often, so it has little impact on the performance of the server. I think I would want to know how much impact a db within a date range.  Is there a way to get these kind of general stats? I'm not looking for expensive queries, detailed user stats, or query optimization here. I'm aware of the SSMS reports, but they seem to be more real-time. The end goal is to divide up our current databases into evenly balanced buckets, and I would think performance is one way to do that.  Thoughts? Wisdom? Any other ideas on how to divvy up the db's?  Thanks! Tom Simplify $\sum (x_i- \mu)^2$ How can I simplify this relation? $$\sum_{i = 1}^m(X_i-\mu)^2=\sum_{i = 1}^m(X_i-\bar{X}_m)^2+m(\bar{X}_m-\mu)^2$$ I know how to set up: $$\sum_{i = 1}^m(X_i-\mu)^2=\sum_{i = 1}^m[(X_i-\bar{X}_m)+(\bar{X}_m-\mu)]^2$$ but when I open the bracket, how do I handle the mixed term? $$2\sum_{i = 1}^m(X_i-\bar{X}_m)(\bar{X}_m-\mu)$$  Thank you! How do I make my screenshot ask me what to do next every time? I take screenshots a lot. I usually take screenshot of an area, I then recheck if I have the desired area and then copy it to clipboard.  I want to change this behaviour so that immediately upon  pressing Shift+PrntScr the screen capture application allows me to select an area, and immediately afterwards it provides me with the option to save to a particular location or clipboard.  I want Shift+PrntScr to bring up a pop-up screen like this: How to switch from Resident visa to Tourist visa status in the Schengen area? Say for a game with irregular hotspots (say Risk, or a strategy game like Paradox's Hearts of Iron or Crusader Kings), how do you   Define a non-rectangular hotspot of irregular shape (much like a territory on a map?), in code? What tool can you use to trace out the hotspot and import into your game? What is the algorithm for detecting if someone has clicked within such a hotspot? Why does the Hilbert curve fill the whole square? I have two checkboxes in a lightning component, when we click on the first checkbox it marks true to the other checkbox, it works well only with the UI tags but doesn't work when I convert it to lightning tag  &lt;ui:inputCheckbox aura:id="box3" change="{!c.selectAll}"/&gt;  &lt;ui:inputCheckbox aura:id="boxPack" value=""                                                          change="{!c.checkboxSelect}"/&gt;   below are the lightning tags  &lt;lightning:input type="checkbox" aura:id="box3" onclick="{!c.selectAll}"/&gt;  &lt;lightning:input type="checkbox" aura:id="boxPack" value=""                                                          onclick="{!c.checkboxSelect}"/&gt;   controller  checkboxSelect: function(component, event, helper) {         // get the selected checkbox value           var selectedRec = event.getSource().get("v.value");         // get the selectedCount attrbute value(default is 0) for add/less numbers.          var getSelectedNumber = component.get("v.selectedCount");         // check, if selected checkbox value is true then increment getSelectedNumber with 1          // else Decrement the getSelectedNumber with 1              if (selectedRec == true) {             getSelectedNumber++;         } else {             getSelectedNumber--;         }         // set the actual value on selectedCount attribute to show on header part.          component.set("v.selectedCount", getSelectedNumber);     },      selectAll: function(component, event, helper) {         //get the header checkbox value           var selectedHeaderCheck = event.getSource().get("v.value");         // get all checkbox on table with "boxPack" aura id (all iterate value have same Id)         // return the List of all checkboxs element          var getAllId = component.find("boxPack");         // If the local ID is unique[in single record case], find() returns the component. not array            if(! Array.isArray(getAllId)){             if(selectedHeaderCheck == true){                  console.log('true');                 component.find("boxPack").set("v.value", true);                 component.set("v.selectedCount", 1);             }else{                 component.find("boxPack").set("v.value", false);                 component.set("v.selectedCount", 0);             }         }else{             // check if select all (header checkbox) is true then true all checkboxes on table in a for loop               // and set the all selected checkbox length in selectedCount attribute.             // if value is false then make all checkboxes false in else part with play for loop              // and select count as 0              if (selectedHeaderCheck == true) {                 for (var i = 0; i &lt; getAllId.length; i++) {                     component.find("boxPack")[i].set("v.value", true);                     component.set("v.selectedCount", getAllId.length);                 }             } else {                 for (var i = 0; i &lt; getAllId.length; i++) {                     component.find("boxPack")[i].set("v.value", false);                     component.set("v.selectedCount", 0);                 }             }          }        }, How to make the tick thickness as the axis line? I am trying to make the thickness of the ticks equal to the axis line thickness. That is what I have so far:  \documentclass{article}   \usepackage{pgfplots}  \pgfplotsset{compat=1.5}   \begin{document}     \begin{tikzpicture}     \begin{axis}[         xlabel=Binding Energy (eV),         ylabel=Intensity (a.\,u.),         xtick pos=left,         x dir= reverse,         ytick = \empty,         every x tick/.style={color=black, thin},         tick align=outside,         xlabel near ticks,         ylabel near ticks,         xmin = 96,         xmax = 108     ]         %\addplot[mark=none] table[x=BE,y=cnts] {si2p.txt};         % This data looks similar:         \addplot[mark=none, smooth] table[x=BE,y=cnts] {             BE      cnts             95      1             98      1             99      10             99.5    5             100 6             101 2             108 2         };      \end{axis}     \end{tikzpicture} \end{document}     But if you take a closer look on the ticks on the outside, you'll see that they are somehow clipped or a least thinner. They are also black so the style seems to work for them.    Is this a bug or can I change the clipping region? And as a second question: is thin the correct value for the thickness? I am using this IC in boost converter configuration :   It steps up the voltage from 16.5V to 23V.   It drives a load current of 270mA.  I need to calculate the input current of the converter.   I understand that output power/input power is efficiency.   Since I know the output power, can I take the efficiency value from the graph 21 of the attached datasheet (86.8% approx - obtained from fig 21 graph) and find the input power?   With the input power, and since I know the input voltage, I can calculate the input current.   Is this the right way?   And I want to check if all the components at the output of the IC are properly rated.   Which parameters and components should I check and how to check?    Sorry for the poor image quality. The two transistors are taken from the SWE pin. Best way to implement keyboard shortcuts in a Windows Forms application? What is the definition and purpose of a pre-amplifier? I find in many places mentions of pre-amplifiers being used to boost audio signals prior to feeding to a power amplifier.  Wikipedia's article on  gives some hints at their usage, but it doesn't really explain why it would be necessary to have two amplifiers in series rather than a single one with greater gain.  If a pre-amp is just a power amp with a smaller gain, what's the point, and why the distinction between the two kinds? Is the distinction in function, or simply purpose? What is the scope of variables in javascript? Do they have the same scope inside as opposed to outside a function? Or does it even matter? Also, where are the variables stored if they are defined globally? Changing the style of the first *typeset* line of a paragraph Is there a word for when an action has an effect opposite to the one intended? Is there a word or phrase to express the concept of an action having the opposite effect of the expected outcome?  For example, a drug taken to cure headaches that actually causes headaches, or an advertising campaign designed to deter smoking that leads to an increase in smoking. I'm new to data mining and I'm trying to train a decision tree against a data set which is highly unbalanced. However, I'm having problems with poor predictive accuracy.  The data consists of students studying courses, and the class variable is the course status which has two values - Withdrawn or Current.   Age Ethnicity Gender Course  ... Course Status   In the data set there are many more instances which are Current than Withdrawn. Withdrawn instances only accounting for 2% of the total instances.  I want to be able to build a model which can predict the probability that a person will withdraw in the future. However when testing the model against the training data, the accuracy of the model is terrible.  I've had similar issues with decision trees where the data is dominated by one or two classes.  What approach can I use to solve this problem and build a more accurate classifier? how I can draw an skew cylinder (rotate around x axis) and fill it (in 3D tikz)? Dodecagon Area Question The distance between two opposite vertices of the dodecagon is 2. Find the area of the dodecagon.  Is there any way to do this without trigonometry?  And could you include a proof also? :O