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  • Making A Dynaically Created Excel Report Downloadable

    - by Nick LaMarca
    I have 2 blocks of code, if someone could help me put them together I would get the functionality I am looking for. The first block of code downloads a gridview to excel using the download dialog I am looking for: Public Overloads Overrides Sub VerifyRenderingInServerForm(ByVal control As Control) ' Verifies that the control is rendered End Sub Private Sub ExportToExcel(ByVal filename As String, ByVal gv As GridView, ByVal numOfCol As Integer) Response.Clear() Response.Buffer = True Response.AddHeader("content-disposition", String.Format("attachment; filename={0}", filename)) Response.Charset = "" Response.ContentType = "application/vnd.ms-excel" Dim sw As New StringWriter() Dim hw As New HtmlTextWriter(sw) gv.AllowPaging = False gv.DataBind() 'Change the Header Row back to white color gv.HeaderRow.Style.Add("background-color", "#FFFFFF") For i As Integer = 0 To numOfCol - 1 gv.HeaderRow.Cells(i).Style.Add("background-color", "blue") gv.HeaderRow.Cells(i).Style.Add("color", "#FFFFFF") Next For i As Integer = 0 To gv.Rows.Count - 1 Dim row As GridViewRow = gv.Rows(i) 'Change Color back to white row.BackColor = System.Drawing.Color.White For j As Integer = 0 To numOfCol - 1 row.Cells(j).Style.Add("text-align", "center") Next 'Apply text style to each Row row.Attributes.Add("class", "textmode") 'Apply style to Individual Cells of Alternating Row If i Mod 2 <> 0 Then For j As Integer = 0 To numOfCol - 1 row.Cells(j).Style.Add("background-color", "#CCFFFF") row.Cells(j).Style.Add("text-align", "center") '#C2D69B 'row.Cells(j).Style.Add("font-size", "12pt") Next End If Next gv.RenderControl(hw) 'style to format numbers to string Dim style As String = "<style> .textmode { mso-number-format:\@; } </style>" Response.Write(style) Response.Output.Write(sw.ToString()) Response.Flush() Response.End() End Sub The second block of code is a sample report I am wish to be downloaded. So instead of downloading a gridview I want this function to accept a worksheet object.

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  • Should convert String to Int in java @ 1.5 or use other method?

    - by NiksBestJPro
    I'm writing a program in which I want to terminate program by pressing any key(whether character or numbers), so I did a conversion from string to int using Integer.parseInt(variable) method and compare choices if it is not desired choice it should terminate the program but it show an error Exception in thread "main" java.lang.NumberFormatException: for input string: "d". program code is as follows:- public class mainClass { public static void main(String[]ar) { double res=0; Scanner in = new Scanner(System.in); Tdata td1 = new Tdata(); //another class object System.out.println("*Temperature Conversion*"); System.out.println("------------------------------"); System.out.println("Press 1- C2F"); System.out.println("Press 2- F2C"); System.out.println("<- Press aNY kEY TO Exit -"); String choice = in.nextLine(); //==================================================================== int ch = Integer.parseInt(choice); System.out.println("String has converted: " +ch); //verifying if converted into int if(ch == 1 || ch == 2) { if(ch == 1) { td1.getVal(37.4); res = td1.C2F(); System.out.println("Resulted Temperature: "+res); } else if(ch == 2) { td1.getVal(104.2); res = td1.F2C(); System.out.println("Resulted Temperature: "+res); } else { System.out.println("mind your input plz"); } } else { System.out.println("<- You select to exit ->"); System.exit(0); } //========================================================================================= }//end of main }//end of public class Now I think that I should convert undesired input to its previous state ie. String state.. is it right way or should Try another predefined method available in api. -Thanks! Niks

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  • A good way to write unit tests

    - by bobobobo
    So, I previously wasn't really in the practice of writing unit tests - now I kind of am and I need to check if I'm on the right track. Say you have a class that deals with math computations. class Vector3 { public: // Yes, public. float x,y,z ; // ... ctors ... } ; Vector3 operator+( const Vector3& a, const Vector3 &b ) { return Vector3( a.x + b.y /* oops!! hence the need for unit testing.. */, a.y + b.y, a.z + b.z ) ; } There are 2 ways I can really think of to do a unit test on a Vector class: 1) Hand-solve some problems, then hard code the numbers into the unit test and pass only if equal to your hand and hard-coded result bool UnitTest_ClassVector3_operatorPlus() { Vector3 a( 2, 3, 4 ) ; Vector3 b( 5, 6, 7 ) ; Vector3 result = a + b ; // "expected" is computed outside of computer, and // hard coded here. For more complicated operations like // arbitrary axis rotation this takes a bit of paperwork, // but only the final result will ever be entered here. Vector3 expected( 7, 9, 11 ) ; if( result.isNear( expected ) ) return PASS ; else return FAIL ; } 2) Rewrite the computation code very carefully inside the unit test. bool UnitTest_ClassVector3_operatorPlus() { Vector3 a( 2, 3, 4 ) ; Vector3 b( 5, 6, 7 ) ; Vector3 result = a + b ; // "expected" is computed HERE. This // means all you've done is coded the // same thing twice, hopefully not having // repeated the same mistake again Vector3 expected( 2 + 5, 6 + 3, 4 + 7 ) ; if( result.isNear( expected ) ) return PASS ; else return FAIL ; } Or is there another way to do something like this?

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  • Effective simulation of compound poisson process in Matlab

    - by Henrik
    I need to simulate a huge bunch of compound poisson processes in Matlab on a very fine grid so I am looking to do it most effectively. I need to do a lot of simulations on the same random numbers but with parameters changing so it is practical to draw the uniforms and normals beforehand even though it means i have to draw a lot more than i will probably need and won't matter much because it will only need to be done once compared to in the order 500*n repl times the actual compound process generation. My method is the following: Let T be for how long i need to simulate and N the grid points, then my grid is: t=linspace(1,T,N); Let nrepl be the number of processes i need then I simulate P=poissrnd(lambda,nrepl,1); % Number of jumps for each replication U=(T-1)*rand(10000,nrepl)+1; % Set of uniforms on (1,T) for jump times N=randn(10000,nrepl); % Set of normals for jump size Then for replication j: Poiss=P(j); % Jumps for replication Uni=U(1:Poiss,j);% Jump times Norm=mu+sigma*N(1:Poiss,j);% Jump sizes Then this I guess is where I need your advice, I use this one-liner but it seems very slow: CPP_norm=sum(bsxfun(@times,bsxfun(@gt,t,Uni),Norm),1); In the inner for each jump it creates a series of same length as t with 0 until jump and then 1 after, multiplying this will create a grid with zeroes until jump has arrived and then the jump size and finally adding all these will produce the entire jump process on the grid. How can this be done more effectively? Thank you very much.

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  • How to get results efficiently out of an Octree/Quadtree?

    - by Reveazure
    I am working on a piece of 3D software that has sometimes has to perform intersections between massive numbers of curves (sometimes ~100,000). The most natural way to do this is to do an N^2 bounding box check, and then those curves whose bounding boxes overlap get intersected. I heard good things about octrees, so I decided to try implementing one to see if I would get improved performance. Here's my design: Each octree node is implemented as a class with a list of subnodes and an ordered list of object indices. When an object is being added, it's added to the lowest node that entirely contains the object, or some of that node's children if the object doesn't fill all of the children. Now, what I want to do is retrieve all objects that share a tree node with a given object. To do this, I traverse all tree nodes, and if they contain the given index, I add all of their other indices to an ordered list. This is efficient because the indices within each node are already ordered, so finding out if each index is already in the list is fast. However, the list ends up having to be resized, and this takes up most of the time in the algorithm. So what I need is some kind of tree-like data structure that will allow me to efficiently add ordered data, and also be efficient in memory. Any suggestions?

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  • XSLT apply attribute depending on position

    - by Burt
    I am using XSLT for a website based on the 960 grid css framework. I have columns of divs that span across the page if it is the first div in a row it should have a class first applied, if it is the middle one then no class and if it is the 3rd in the row it should have the class last applied. I am really scratching my head as the best way to go about this any help is appreciated. Below is the structure I want to end up with, the numbers inside the divs represent the position. <div class="container_12"> <div id="main-content" class="alpha grid_12" style="margin-bottom: 20px;"> <div class="grid_4 alpha"> 1 </div> <div class="grid_4 "> 2 </div> <div class="grid_4 omega"> 3 </div> <div class="grid_4 alpha"> 4 </div> </div> </div>

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  • PHP Saving information to MySQL but not using hard coded code

    - by Homer_J
    Hi guys, Thanks everyone for assisting me but know I'm well and truely stuck...hopefully someone can advise? My current code that saves to a MySQL database: $q1 = $_POST["q1"]; $q2 = $_POST["q2"]; $q3 = $_POST["q3"]; $q4 = $_POST["q4"]; $q5 = $_POST["q5"]; $q6 = $_POST["q6"]; $q7 = $_POST["q7"]; $q8 = $_POST["q8"]; $proc = mysqli_prepare($link, "INSERT INTO tresults_bh_main (respondent_id, ip, browser, q1, q2, q3, q4, q5, q6, q7, q8) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?);"); mysqli_stmt_bind_param($proc, "issiiiiiiii", $respondent_id, $ip, $browser, $q1, $q2, $q3, $q4, $q5, $q6, $q7, $q8); At the moment this is all hard coded and I need it to use variables: I have an array which stores the following information: $qs['questions'] - stores, for example q1, q2, q3, q4 etc - obviously these change both in terms of of numbers, ie. q10, q11, q12 and also the amount in the array - so there could be 4 q's or 10 q's stored in the array. What I struggling to get my head around is how I would set-up this hard coded page to work with my variables. If anyone can help, much appreciated. Homer.

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  • Scan file contents into an array of a structure.

    - by ZaZu
    Hello, I have a structure in my program that contains a particular array. I want to scan a random file with numbers and put the contents into that array. This is my code : ( NOTE : This is a sample from a bigger program, so I need the structure and arrays as declared ) The contents of the file are basically : 5 4 3 2 5 3 4 2 #include<stdio.h> #define first 500 #define sec 500 struct trial{ int f; int r; float what[first][sec]; }; int trialtest(trial *test); main(){ trial test; trialtest(&test); } int trialtest(trial *test){ int z,x,i; FILE *fin; fin=fopen("randomfile.txt","r"); for(i=0;i<5;i++){ fscanf(fin,"%5.2f\t",(*test).what[z][x]); } fclose(fin); return 0; } But the problem is, whenever this I run this code, I get this error : (25) : warning 508 - Data of type 'double' supplied where a pointer is required I tried adding do{ for(i=0;i<5;i++){ q=fscanf(fin,"%5.2f\t",(*test).what[z][x]); } }while(q!=EOF); But that didnt work either, it gives the same error. Does anyone have a solution to this problem ?

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  • jQuery $.each()-problem

    - by Volmar
    Hi, im making a wordpress plugin and i have a function where i import images, this is done with a $.each()-loop that calls a .load()-function every iteration. The load-function page the load-function calls is downloading the image and returns a number. The number is imported into a span-element. The source and destination Arrays is being imported from LI-elemnts of a hidden ULs. this way the user sees a counter counting from zero up to the total number of images being imported. You can se my jQuery code below: jQuery(document).ready(function($) { $('#mrc_imp_img').click(function(){ var dstA = []; var srcA = []; $("#mrc_dst li").each(function() { dstA.push($(this).text()) }); $("#mrc_src li").each(function() { srcA.push($(this).text()) }); $.each(srcA, function (i,v) { $('#mrc_imgimport span.fc').load('/wp-content/plugins/myplugin/imp.php?num='+i+'&dst='+dstA[i]+'&src='+srcA[i]); }); }); }); This works pretty good but sometimes it looks like the load function isn't updating the DOM as fast as it should because sometimes the numbers that the span is updated with is lower than the previous and almost everytime a lower number is replacing the last number in the end. How can i prevent this from happening and how can i make it hide '#mrc_imp_img' when the $.each-loop is ready?

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  • Win conditions for a connect-4 like game

    - by FrozenWasteland
    I have an 5x10 array that is populated with random values 1-5. I want to be able to check when 3 numbers, either horizontally, or vertically, match. I can't figure out a way to do this without writing a ton of if statements. Here is the code for the randomly populated array int i; int rowincrement = 10; int row = 0; int col = 5; int board[10][5]; int randomnum = 5; int main(int argc, char * argv[]) { srand(time(NULL)); cout << "============\n"; while(row < rowincrement) { for(i = 0; i < 5; i++) { board[row][col] = rand()%5 + 1; cout << board[row][col] << " "; } cout << endl; cout << "============\n"; row++; } cout << endl; return 0; }

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  • Parse particular text from an XML string

    - by Dan Sewell
    Hi all, Im writing an app which reads an RSS feed and places items on a map. I need to read the lat and long numbers only from this string: http://www.xxxxxxxxxxxxxx.co.uk/map.aspx?isTrafficAlert=true&lat=53.647351&lon=-1.933506 .This is contained in link tags Im a bit of a programming noob but im writing this in C#/Silverlight using Linq to XML. Shold this text be extrated when parsing or after parsing and sent to a class to do this? Many thanks for your assistance. EDIT. Im going to try and do a regex on this this is where I need to integrate the regex somewhere in this code. I need to take the lat and long from the Link element and seperate it into two variables I can use (the results are part of a foreach loop that creates a list.) var events = from ev in document.Descendants("item") select new { Title = (ev.Element("title").Value), Description = (ev.Element("description").Value), Link = (ev.Element("link").Value), }; Question is im not quite ure where to put the regex (once I work out how to use the regex properly! :-) )

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  • split a string into a key => value array in php

    - by andy-score
    +2-1+18*+7-21+3*-4-5+6x29 The above string is an example of the kind of string I'm trying to split into either a key = value array or something similar. The numbers represent the id of a class and -,+ and x represent the state of the class (minimised, expanded or hidden), the * represents a column break. I can split this into the columns easily using explode which gives and array with 3 $key = $value associations. eg. $column_layout = array( [0] => '+2-1+18' , [1] => '+7-21+3' , [2] => '-4-5+6x29' ) I then need to split this into the various classes from there, keeping the status and id together. eg. $column1 = array( '+' => 2 , '-' => 1 , '+' => 18 ) ... or $column1 = array( array( '+' , 2 ) , array( '-' , 1 ) , array( '+' , 18 ) ) ... I can't quite get my head round this and what the best way to do it is, so any help would be much appreciated.

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  • Printing distinct integers in an array

    - by ???
    I'm trying to write a small program that prints out distinct numbers in an array. For example if a user enters 1,1,3,5,7,4,3 the program will only print out 1,3,5,7,4. I'm getting an error on the else if line in the function checkDuplicate. Here's my code so far: import javax.swing.JOptionPane; public static void main(String[] args) { int[] array = new int[10]; for (int i=0; i<array.length;i++) { array[i] = Integer.parseInt(JOptionPane.showInputDialog("Please enter" + "an integer:")); } checkDuplicate (array); } public static int checkDuplicate(int array []) { for (int i = 0; i < array.length; i++) { boolean found = false; for (int j = 0; j < i; j++) if (array[i] == array[j]) { found = true; break; } if (!found) System.out.println(array[i]); } return 1; } }

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  • undefined method `output_data' for #<EventManager:0x007fa4220320c8> (NoMethodError)

    - by Roger Camps
    I keep getting this error: event_manager.rb:83:in': undefined method output_data' for #<EventManager:0x007fc5018320c0> (NoMethodError) I am following the exercise on this website: Here is my code (My error comes towards the end with DEF OUTPUT_DATA ...): # Dependencies require "csv" # Class Definition class EventManager INVALID_PHONE_NUMBER = "0000000000" INVALID_ZIPCODE = "00000" def initialize puts "EventManager Initialized." filename = "event_attendees.csv" @file = CSV.open(filename, {:headers => true, :header_converters => :symbol}) end def print_names @file.each do |line| puts line.inspect puts line[2] + " " + line[3] end end #printing home phone number method def print_numbers @file.each do |line| number = clean_number(line[:homephone]) puts number end end #cleaning numbers method def clean_number(number) cleaner= number.delete('.' + ')' + '(' + '-') if cleaner.length == 10 # Do Nothing elsif cleaner.length == 11 if cleaner.start_with?("1") cleaner = cleaner[1..-1] else cleaner = INVALID_PHONE_NUMBER end else cleaner = INVALID_PHONE_NUMBER end return cleaner end def clean_zipcode(original) if original.nil? zipcode = INVALID_ZIPCODE elsif original.length < 5 while original.length < 5 original = original.insert(0, "0") end else return original end return zipcode end def print_zipcodes @file.each do |line| zipcode = clean_zipcode(line[:zipcode]) puts zipcode end def output_data output = CSV.open("event_attendees_clean.csv", "w") @file.each do |line| output << line end end end end # Script manager = EventManager.new #manager.print_numbers #manager.print_zipcodes manager.output_data I've tried several things, checked all through the internet and I just can't figure it out myself. I will really appreciate any help. Thank you in advance!

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  • sprintf bug with php & apache in windows?

    - by potatoe
    I've run into a strange problem on a WAMP server setup (PHP version 5.3.0, Apache 2.2.11). When using sprintf to output a number, I occasionally get erroneous characters in the output string. Example: (not trimmed from anything, this is the only code in the script) $dt1 = new DateTime('now'); $dt2 = new DateTime('now - 10 min'); $interval = $dt1->diff($dt2); $number = 10.0; $string = sprintf("%.1f", $number); echo "number: $number, string: $string\n"; If I run this at the command prompt with PHP CLI, I get the expected output: number: 10, string: 10.0 However, if I serve it using Apache, in the browser I get number: 10, string: :.0 with a colon where '10' should be. (Note that ':' is the next ascii character in sequence after '9', if $number is 0-9, everything works. Numbers greater than 10 appear to use ascii equivalents - so 11 is ';', 12 is '<', etc.) The strangest part is that the first four lines in the above code sample seem to affect the results. Logically, those statements should have no impact, but if I comment them out or remove them the problem goes away. Any ideas? Anyone else able to replicate this?

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  • Possible to push a hash value only if it is unique?

    - by Structure
    In the example code below, assuming that the value $keyvalue is constantly changing, I am attempting to use a single line (or something similarly contained) to test and see if the current $keyvalue already exists. If it does, then do nothing. If it does not, then push it. This line would reside within a while statement which is why it needs to be contained within a few lines. Preserving order does not matter as long as there are no duplicate values. my $key = "numbers"; my $keyvalue = 1; my %hash = ($key => '1'); push (@{$hash{$key}}, $keyvalue) unless exists $hash{$key}; I am not getting any errors with use strict; use warnings;, but at the same time this is not working. In the example above, I would expect that since the default value is 1 that the $keyvalue would not be pushed as it is also 1. Perhaps I have gotten myself all turned around... Are there adjustments to get this to work or any alternatives that can be used instead to accomplish the same thing?

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  • How to set up a functional macro with parameters in C++?

    - by user1728737
    is there a way that I can make this work? Or do I need to use separate files? #include <iostream> // Necessary using namespace std; long double primary, secondary, tertiary; #define long double mMaxOf2(long double min, long double max) { return ((max > min) ? (max) : (min)); } #define long double mMaxOf3(long double Min, long double Max, long double Mid) { long double Mid = (long double mMaxOf2(long double Min, long double Mid)); long double Max = (long double mMaxOf2(long double Mid, long double Max)); return (Max); } int main() { cout << "Please enter three numbers: "; cin << primary << secondary << tertiary; cout << "The maximum of " << primary << " " << secondary << " " << tertiary; cout << " using mMaxOf3 is " << long double mMaxOf3(primary, secondary, tertiary); return 0; } This is the error that I am getting. |20|error: expected unqualified-id before '{' token|

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  • Generating all unique crossword puzzle grids

    - by heydenberk
    I want to generate all unique crossword puzzle grids of a certain grid size (4x4 is a good size). All possible puzzles, including non-unique puzzles, are represented by a binary string with the length of the grid area (16 in the case of 4x4), so all possible 4x4 puzzles are represented by the binary forms of all numbers in the range 0 to 2^16. Generating these is easy, but I'm curious if anyone has a good solution for how to programmatically eliminate invalid and duplicate cases. For example, all puzzles with a single column or single row are functionally identical, hence eliminating 7 of those 8 cases. Also, according to crossword puzzle conventions, all squares must be contiguous. I've had success removing all duplicate structures, but my solution took several minutes to execute and probably was not ideal. I'm at something of a loss for how to detect contiguity so if anyone has ideas on this it'd be much appreciated. I'd prefer solutions in python but write in whichever language you prefer. If anyone wants, I can post my python code for generating all grids and removing duplicates, slow as it may be.

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  • Magic squares, recursive

    - by user310827
    Hi, my problem is, I'm trying to permute all posibilities for a 3x3 square and check if the combination is magic. I've added a tweak with (n%3==0) if statement that if the sum of numbers in row differs from 15 it breaks the creation of other two lines... but it doesn't work. Any suggestions? I call the function with Permute(1). public static class Global { //int[] j = new int[6]; public static int[] a= {0,0,0,0,0,0,0,0,0}; public static int[] b= {0,0,0,0,0,0,0,0,0}; public static int count = 0; } public static void Permute(int n) { int tmp=n-1; for (int i=0;i<9;i++){ if (Global.b[i]==0 ) { Global.b[i]=1; Global.a[n-1]=i+1; if ((n % 3) == 0) { if (Global.a[0+tmp]+Global.a[1+tmp]+Global.a[2+tmp] == 15) { if (n<9) { Permute(n+1); } else { isMagic(Global.a); } } else break; } else { Permute(n+1); } Global.b[i]=0; } } }

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  • Looking for an email/report templating engine with database backend - for end-users ...

    - by RizwanK
    We have a number of customers that we have to send monthly invoices too. Right now, I'm managing a codebase that does SQL queries against our customer database and billing database and places that data into emails - and sends it. I grow weary of maintaining this every time we want to include a new promotion or change our customer service phone numbers. So, I'm looking for a replacement to move more of this into the hands of those requesting the changes. In my ideal world, I need : A WYSIWYG (man, does anyone even say that anymore?) email editor that generates templates based upon the output from a Database Query. The ability to drag and drop various fields from the database query into the email template. Display of sample email results with the database query. Web application, preferably not requiring IIS. Involve as little code as possible for the end-user, but allow basic functionality (i.e. arrays/for loops) Either comes with it's own email delivery engine, or writes output in a way that I can easily write a Python script to deliver the email. Support for generic Database Connectors. (I need MSSQL and MySQL) F/OSS So ... can anyone suggest a project like this, or some tools that'd be useful for rolling my own? (My current alternative idea is using something like ERB or Tenjin, having them write the code, but not having live-preview for the editor would suck...)

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  • how to do sorting using java

    - by karthikacyr
    hi friends, I have text file with list of alphabets and numbers. I want to do sorting w.r.t this number using java. My text file looks like this: a---12347 g---65784 r---675 I read the text file and i split it now. But i dont know how to perform sorting . I am new to java. Please give me a idea. My output want to be g---65784 a---12347 r---675 Plese help me. Thanks in advance. My coding is String str = ""; BufferedReader br = new BufferedReader(new FileReader("counts.txt")); while ((str = br.readLine()) != null) { String[] get = str.split("----"); When i search the internet all suggest in the type of arrays. I tried. But no use.How to inlude the get[1] into array. int arr[]=new int[50] arr[i]=get[1]; for(int i=0;i<50000;i++){ for(int j=i+1;j<60000;j++){ if(arr[i]arr[j]){ System.out.println(arr[i]); } }

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  • Best way to store data in database when you don't know the type

    - by stiank81
    I have a table in my database that represents datafields in a custom form. The DataField gives some representation of what kind of control it should be represented with, and what value type it should take. Simplified you can say that I have 2 entities in this table - Textbox taking any string and Textbox only taking numbers. Now I have the different values stored in a separate table, referencing the datafield definition. What is the best way to store the data value here, when the type differs? One possible solution is to have the FieldValue table hold one field per possible value type. Now this would certainly be redundant, but at least I would get the value stored in its correct form - simplifying queries later. FieldValue ---------- Id DataFieldId IntValue DoubleValue BoolValue DataValue .. Another possibility is just storing everything as String, and casting this in the queries. I am using .Net with NHibernate, and I see that at least here there is a Projections.Cast that can be used to cast e.g. string to int in the query. Either way in these two solutions I need to know which type to use when doing the query, but I will know that from the DataField, so that won't be a problem. Anyway; I don't think any of these solutions sounds good. Are they? Or is there a better way?

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  • memcached: which is faster, doing an add (and checking result), or doing a get (and set when returni

    - by Mike Sherov
    The title of this question isn't so clear, but the code and question is straightforward. Let's say I want to show my users an ad once per day. To accomplish this, every time they visit a page on my site, I check to see if a certain memcache key has any data stored on it. If so, don't show an ad. If not, store the value '1' in that key with an expiration of 86400. I can do this 2 ways: //version a $key='OPD_'.date('Ymd').'_'.$type.'_'.$user; if($memcache->get($key)===false){ $memcache->set($key,'1',false,$expire); //show ad } //version b $key='OPD_'.date('Ymd').'_'.$type.'_'.$user; if($memcache->add($key,'1',false,$expire)){ //show ad } Now, it might seem obvious that b is better, it always makes 1 memcache call. However, what is the overhead of "add" vs. "get"? These aren't the real comparisons... and I just made up these numbers, but let's say 1 add ~= 1 set ~= 5 get in terms of effort, and the average user views 5 pages a day: a: (5 get * 1 effort) + (1 set * 5 effort) = 10 units of effort b: (5 add * 5 effort) = 25 units of effort Would it make sense to always do the add call? Is this an unnecessary micro-optimization?

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  • Given a 2d array sorted in increasing order from left to right and top to bottom, what is the best w

    - by Phukab
    I was recently given this interview question and I'm curious what a good solution to it would be. Say I'm given a 2d array where all the numbers in the array are in increasing order from left to right and top to bottom. What is the best way to search and determine if a target number is in the array? Now, my first inclination is to utilize a binary search since my data is sorted. I can determine if a number is in a single row in O(log N) time. However, it is the 2 directions that throw me off. Another solution I could use, if I could be sure the matrix is n x n, is to start at the middle. If the middle value is less than my target, then I can be sure it is in the left square portion of the matrix from the middle. I then move diagnally and check again, reducing the size of the square that the target could potentially be in until I have honed in on the target number. Does anyone have any good ideas on solving this problem? Example array: Sorted left to right, top to bottom. 1 2 4 5 6 2 3 5 7 8 4 6 8 9 10 5 8 9 10 11

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  • Help with java threads or executors: Executing several MySQL selects, inserts and updates simmultane

    - by Martin
    Hi. I'm writing an application to analyse a MySQL database, and I need to execute several DMLs simmultaneously; for example: // In ResultSet rsA: Select * from A; rsA.beforeFirst(); while (rsA.next()) { id = rsA.getInt("id"); // Retrieve data from table B: Select * from B where B.Id=" + id; // Crunch some numbers using the data from B // Close resultset B } I'm declaring an array of data objects, each with its own Connection to the database, which in turn calls several methods for the data analysis. The problem is all threads use the same connection, thus all tasks throw exceptios: "Lock wait timeout exceeded; try restarting transaction" I believe there is a way to write the code in such a way that any given object has its own connection and executes the required tasks independent from any other object. For example: DataObject dataObject[0] = new DataObject(id[0]); DataObject dataObject[1] = new DataObject(id[1]); DataObject dataObject[2] = new DataObject(id[2]); ... DataObject dataObject[N] = new DataObject(id[N]); // The 'DataObject' class has its own connection to the database, // so each instance of the object should use its own connection. // It also has a "run" method, which contains all the tasks required. Executor ex = Executors.newFixedThreadPool(10); for(i=0;i<=N;i++) { ex.execute(dataObject[i]); } // Here where the problem is: Each instance creates a new connection, // but every DML from any of the objects is cluttered in just one connection // (in MySQL command line, "SHOW PROCESSLIST;" throws every connection, and all but // one are idle). Can you point me in the right direction? Thanks

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