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• DB optimization to use it as a queue

  - by anony

  We have a table called worktable which has some columns(key(primary key), ptime, aname, status, content) we have something called producer which puts in rows in this table and we have consumer which does an order-by on the key column and fetches the first row which has status as 'pending'. The consumer does some processing on this row: 1. updates status to "processing" 2. does some processing using content 3. deletes the row we are facing contention issues when we try to run multiple consumers(probably due to the order-by which does a full table scan)... using Advanced queues would be our next step but before we go there we want to check what is the max throughput we can achieve with multiple consumers and producer on the table. What are the optimizations we can do to get the best numbers possible? Can we do an in-memory processing where a consumer fetches 1000 rows at a time processes and deletes? will that improve? What are other possibilities? partitioning of table? parallelization? Index organized tables?...

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• Summary statistics in visual basic

  - by ben

  Below I am trying to write a script the goal of which is to calculate some summary statistics for a few different columns of numbers. I have gotten some help on it up to the "Need help below" mark. But beyond that I am flabergasted as to how to calculate the simple stats (sum, mean, standard deviation, coefficient of variation). I know VB has scripts for these stats, which I have included in my code, but I guess I need to do some extra declaring or something. Advice much appreciated. Thanks. Sub TOAinput() Const n As Integer = 648 Dim stratum(n), hybrid(n), acres(n), hhsz(n), offinc(n) Dim s1 As Integer Dim s2 As Integer Dim i As Integer For i = 1 To n stratum(i) = Worksheets("hhid level").Cells(i + 1, 2).Value Next i s1 = 0 s2 = 0 For i = 1 To n If stratum(i) = 1 Then s1 = s1 + 1 Else: s2 = s2 + 1 End If Next i Dim acres1(), hhsz1(), offinc1(), acres2(), hhsz2(), offinc2() ReDim acres1(s1), hhsz1(s1), offinc1(s1), acres2(s2), hhsz2(s2), offinc2(s2) 'data infiles: acres, hh size, off-farm income, For i = 1 To n acres(i) = Worksheets("hhid level").Cells(i + 1, 4).Value hhsz(i) = Worksheets("hhid level").Cells(i + 1, 5).Value offinc(i) = Worksheets("hhid level").Cells(i + 1, 6).Value Next i s1 = 0 s2 = 0 For i = 1 To n If stratum(i) = 1 Then s1 = s1 + 1 acres1(s1) = acres(i) hhsz1(s1) = hhsz(i) offinc1(s1) = offinc(i) Else: s2 = s2 + 1 acres2(s2) = acres(i) hhsz2(s2) = hhsz(i) offinc2(s2) = offinc(i) End If Next i '**************************** 'Need help below '**************************** Dim sumac1, sumac2, mhhsz1, mhhsz2, cvhhsz1, cvhhsz2 sumac1 = Sum(acres1) sumac2 = Sum(acres2) mhhsz1 = Average(hhsz1) mhhsz2 = Average(hhsz2) cvhhsz1 = StDev(hhsz1) / Average(hhsz1) cvhhsz2 = StDev(hhsz2) / Average(hhsz2) End Sub

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• Custom Tile Layer Problem

  - by Myra

  Hi,I'm currently implementing logic on custom tile layers via OpenLayers function getTiles() { var res = this.map.getResolution(); var x = Math.round((bounds.left - this.maxExtent.left) / (res * this.tileSize.w)); var y = Math.round((this.maxExtent.top - bounds.top) / (res * this.tileSize.h)); var z = this.map.getZoom(); return ......; } What I need to is to carry this code in Google API v3. As I searched documentation I found this code to work with: var customtile = new google.maps.ImageMapType({ getTileUrl: function (coord, zoom) { .... .... } Unfortonately,I cannot convert logic in OpenLayers code to Google. As I know resolution is 180 * tileSize.w / Math.pow(2, zoom) //where tileSize is 256x256 Since Google projection is same with my tiles WGS84 boundary should be -180,-90,90,180 I need to calculate to extent coordinates,but in function getTileUrl,there are two arguments.One of which is zoom,but the other coord is some x,y pair which I dont understand what that is.What is that exactly ? How can I generalize formula for calculating tile numbers in Google Maps? Thank you Myra

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• Strange type-related error

  - by vsb

  I wrote following program: isPrime x = and [x `mod` i /= 0 | i <- [2 .. truncate (sqrt x)]] primes = filter isPrime [1 .. ] it should construct list of prime numbers. But I got this error: [1 of 1] Compiling Main ( 7/main.hs, interpreted ) 7/main.hs:3:16: Ambiguous type variable `a' in the constraints: `Floating a' arising from a use of `isPrime' at 7/main.hs:3:16-22 `RealFrac a' arising from a use of `isPrime' at 7/main.hs:3:16-22 `Integral a' arising from a use of `isPrime' at 7/main.hs:3:16-22 Possible cause: the monomorphism restriction applied to the following: primes :: [a] (bound at 7/main.hs:3:0) Probable fix: give these definition(s) an explicit type signature or use -XNoMonomorphismRestriction Failed, modules loaded: none. If I specify signature for isPrime function explicitly: isPrime :: Integer -> Bool isPrime x = and [x `mod` i /= 0 | i <- [2 .. truncate (sqrt x)]] I can't even compile isPrime function: [1 of 1] Compiling Main ( 7/main.hs, interpreted ) 7/main.hs:2:45: No instance for (RealFrac Integer) arising from a use of `truncate' at 7/main.hs:2:45-61 Possible fix: add an instance declaration for (RealFrac Integer) In the expression: truncate (sqrt x) In the expression: [2 .. truncate (sqrt x)] In a stmt of a list comprehension: i <- [2 .. truncate (sqrt x)] 7/main.hs:2:55: No instance for (Floating Integer) arising from a use of `sqrt' at 7/main.hs:2:55-60 Possible fix: add an instance declaration for (Floating Integer) In the first argument of `truncate', namely `(sqrt x)' In the expression: truncate (sqrt x) In the expression: [2 .. truncate (sqrt x)] Failed, modules loaded: none. Can you help me understand, why am I getting these errors?

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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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• SQL query for the latest record for each day

  - by Mac

  I've got an Oracle 10g database with a table with a structure and content very similar to the following: CREATE TABLE MyTable ( id INTEGER PRIMARY KEY, otherData VARCHAR2(100), submitted DATE ); INSERT INTO MyTable VALUES (1, 'a', TO_DATE('28/04/2010 05:13', ''DD/MM/YYYY HH24:MI)); INSERT INTO MyTable VALUES (2, 'b', TO_DATE('28/04/2010 03:48', ''DD/MM/YYYY HH24:MI)); INSERT INTO MyTable VALUES (3, 'c', TO_DATE('29/04/2010 05:13', ''DD/MM/YYYY HH24:MI)); INSERT INTO MyTable VALUES (4, 'd', TO_DATE('29/04/2010 17:16', ''DD/MM/YYYY HH24:MI)); INSERT INTO MyTable VALUES (5, 'e', TO_DATE('29/04/2010 08:49', ''DD/MM/YYYY HH24:MI)); What I need to do is query the database for the latest record submitted on each given day. For example, with the above data I would expect the records with ID numbers 1 and 4 to be returned, as these are the latest each for 28 April and 29 April respectively. Unfortunately, I have little expertise as far as SQL is concerned. Could anybody possibly provide some insight as to how to achieve this? Thanks in advance!

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• Port Java Application to Android

  - by mihirk

  I am not so sure about the question or what I should call what I am trying to achieve. I use a dialer called super sify. Here is the download - http://thegoan.com/supersify/supersify.zip The when extracted it has two files for linux, one is a .jar file which consists of some classes. The application was written in java. The other is a .sh file, which is a shell executable and takes some parameters like username and password and machine id and stuff. I want to port this app to android. What exactly would I have to do. Some more information is the .jar file is named supersify.jar and the .sh file is named ss.sh so here is the code for ss.sh java -jar supersify.jar $* if [ $? -eq 1 ] then read fi Please help me out. This is an open source software.So I am not doing any illegal modifications. I need to port this app to android, so would I have to write the whole thing again or just something else. I know some basic hello world android app development, and I have made an app to add two numbers, I am still on my way to become an android app developer, but I need this app and will learn a lot to make this possible unless it involves rewriting all the java classes. Thank you in advance If you have anymore question I will be glad to answer to them :D.

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• IDENTITY_INSERT ON inside of cursor does not allow inserted id

  - by Mac

  I am trying to set some id's for a bunch of rows in a database where the id column is an identity. I've created a cursor to loop through the rows and update the ids with incrementing negative numbers (-1,-2,-3 etc). When I updated just one row turning on the IDENTITY_INSERT it worked fine but as soon as I try and use it in a cursor, it throws the following error. Msg 8102, Level 16, State 1, Line 22 Cannot update identity column 'myRowID'. DECLARE @MinId INT; SET @MinId = (SELECT MIN(myRowId) FROM myTable)-1; DECLARE myCursor CURSOR FOR SELECT myRowId FROM dbo.myTable WHERE myRowId > 17095 OPEN myCursor DECLARE @myRowId INT FETCH NEXT FROM myCursor INTO @myRowId WHILE (@@FETCH_STATUS <> -1) BEGIN SET IDENTITY_INSERT dbo.myTable ON; --UPDATE dbo.myTable --SET myRowId = @MinId --WHERE myRowId = @myRowId; PRINT (N'ID: ' + CAST(@myRowId AS VARCHAR(10)) + N' NewID: ' + CAST(@MinId AS VARCHAR(4))); SET @MinId = @MinId - 1; FETCH NEXT FROM myCursor INTO @myRowId END CLOSE myCursor DEALLOCATE myCursor GO SET IDENTITY_INSERT dbo.myTable OFF; GO Does anyone know what I'm doing wrong?

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• Find all A^x in a given range

  - by Austin Henley

  I need to find all monomials in the form AX that when evaluated falls within a range from m to n. It is safe to say that the base A is greater than 1, the power X is greater than 2, and only integers need to be used. For example, in the range 50 to 100, the solutions would be: 2^6 3^4 4^3 My first attempt to solve this was to brute force all combinations of A and X that make "sense." However this becomes too slow when used for very large numbers in a big range since these solutions are used in part of much more intensive processing. Here is the code: def monoSearch(min, max): base = 2 power = 3 while 1: while base**power < max: if base**power > min: print "Found " + repr(base) + "^" + repr(power) + " = " + repr(base**power) power = power + 1 base = base + 1 power = 3 if base**power > max: break I could remove one base**power by saving the value in a temporary variable but I don't think that would make a drastic effect. I also wondered if using logarithms would be better or if there was a closed form expression for this. I am open to any optimizations or alternatives to finding the solutions.

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• Prolog, check if term is power of 2

  - by Riku

  i have written following code, which should work with my logic, but it does not. I should check if given term is power of two. For example s(s(s(nul))) should return false, s(s(s(s(nul))) should return true. substractWhileY(X,0,rezult). substractWhileY(s(X),Y,rezult):- Y > 0, number is 1, substractWhileY(X,Y - number, rezult). degreeOftwo(X):- substractWhileY(X,2,rezult), pagalba(X, 2, rezult). calculateAnswer(X, currentCounter, currentValue):- currentCounter is currentCounter * 2, substractWhileY(currentValue, currentCounter , rezult), rezult\= null, calculateAnswer(X, currentCounter , rezult). My idea was to check if given therm is degree of any two and if it is not than it is not the degree of two. With numbers it should work like this. For example i give number 8. First time it checks if 8 - 2 = 0. second time if 8 - 4 = 0. third time if 8 - 8 = 0. so the 8 id power of two. Maybe other solution would work better, so thanks for any help.

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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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• Storing "binary" data type in C program

  - by puchu

  I need to create a program that converts one number system to other number systems. I used itoa in Windows (Dev C++) and my only problem is that I do not know how to convert binary numbers to other number systems. All the other number systems conversion work accordingly. Does this involve something like storing the input to be converted using %? Here is a snippet of my work: case 2: { printf("\nEnter a binary number: "); scanf("%d", &num); itoa(num,buffer,8); printf("\nOctal %s",buffer); itoa(num,buffer,10); printf("\nDecimal %s",buffer); itoa(num,buffer,16); printf("\nHexadecimal %s \n",buffer); break; } For decimal I used %d, for octal I used %o and for hexadecimal I used %x. What could be the correct one for binary? Thanks for future answers!

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• C# and Excel best practices

  - by rlp

  I am doing a lot of MS Excel interop i C# (Visual Studio 2012) using Microsoft.Office.Interop.Excel. It requires a lot of tiresome manual code to include Excel formulas, doing formatting of text and numbers, and making graphs. I would like it very much if any of you have some input on how I do the task better. I have been looking at Visual Studio Tools for Office, but I am uncertain on its functions. I get it is required to make Excel add-ins, but does it help doing Excel automation? I have desperately been trying to find information on working with Excel in Visual Studio 2012 using C#. I did found some good but short tutorials. However I really would like a book an the subject to learn the field more in depth regarding functionality and best practices. Searching Amazon with my limited knowlegde only gives me book on VSTO using older versions of Visual Studio. I would not like to use VBA. My applications use Excel mainly for visualizing compiled from different sources. I also to data processing where Excel is not required. Futhermore, I can write C# but not VB.

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• Dealing with Struts2 float conversion type

  - by Daniel Calderon Mori

  I have a question regarding float type conversion in Struts2. I have a form that contains a serie of normal input elements. A serie of textfields with an add button by the side of each one is included in the window. Clicking on one of this buttons has the effect of adding an input type "hidden" inside the form with the value of its correspondent textfield. That value will often be a float number that, this is very important, uses the point format (example: 1.34). The inputs created look like this: <input class="hidden_material" type="hidden" name="form[0].cantidad_formulacion" value='1.34'"> <input class="hidden_material" type="hidden" name="form[1].cantidad_formulacion" value='1.54'"> Anyway, the whole proccess is made correctly until the data is used by the server after the form submission. The numbers are present as if the point wouldn't have been placed in the number (using the example above, as 134). If a comma is used (as in 1,34), there wouldn't be a problem. But that will not be the case with the users of the system. How could I solve this problem?

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• How to round a number to n decimal places in Java

  - by Alex Spurling

  What I'd like is a method to convert a double to a string which rounds using the half-up method. I.e. if the decimal to be rounded is a 5, it always rounds up the previous number. This is the standard method of rounding most people expect in most situations. I also would like only significant digits to be displayed. That is there should not be any trailing zeroes. I know one method of doing this is to use the String.format method: String.format("%.5g%n", 0.912385); returns: 0.91239 which is great, however it always displays numbers with 5 decimal places even if they are not significant: String.format("%.5g%n", 0.912300); returns: 0.91230 Another method is to use the DecimalFormatter: DecimalFormat df = new DecimalFormat("#.#####"); df.format(0.912385); returns: 0.91238 However as you can see this uses half-even rounding. That is it will round down if the previous digit is even. What I'd like is this: 0.912385 -> 0.91239 0.912300 -> 0.9123 What is the best way to achieve this in Java?

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• Generate regular expression to match strings from the list A, but not from list B

  - by Vlad

  I have two lists of strings ListA and ListB. I need to generate a regular expression that will match all strings in ListA and will not match any string in ListB. The strings could contain any combination of characters, numbers and punctuation. If a string appears on ListA it is guaranteed that it will not be in the ListB. If a string is not in either of these two lists I don't care what the result of the matching should be. The lists typically contain thousands of strings, and strings are fairly similar to each other. I know the trivial answer to this question, which is just generate a regular expression of the form (Str1)|(Str2)|(Str3) where StrN is the string from ListA. But I am looking for a more efficient way to do this. Ideal solution would be some sort of tool that will take two lists and generate a Java regular expression for this. Update 1: By "efficient", I mean to generate expression that is shorter than trivial solution. The ideal algorithm would generate the shorted possible expression. Here are some examples. ListA = { C10 , C15, C195 } ListB = { Bob, Billy } The ideal expression would be /^C1.+$/ Another example, note the third element of ListB ListA = { C10 , C15, C195 } ListB = { Bob, Billy, C25 } The ideal expression is /^C[^2]{1}.+$/ The last example ListA = { A , D ,E , F , H } ListB = { B , C , G , I } The ideal expression is the same as trivial solution which is /^(A|D|E|F|H)$/ Also, I am not looking for the ideal solution, anything better than trivial would help. I was thinking along the lines of generating the list of trivial solutions, and then try to merge the common substrings while watching that we don't wander into ListB territory. *Update 2: I am not particularly worried about the time it takes to generate the RegEx, anything under 10 minutes on the modern machine is acceptable

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• I asked a question about arrays before, but this one won't compile

  - by unit

  I asked about this array a little while ago, and I can't see what the problem is. Too tired. What have I done wrong? Basically, I am taking a string array and trying to check to see if it contains numbers or an x (ISBN number validation). I want to take the number from a given input (bookNum), check the input, and feed any valid input into a new array (book). At the line 'bookNum.charAt[j]==book[i]' I get the 'not a statement error'. What gives? String[] book = new String [ISBN_NUM]; bookNum.replaceAll("-",""); if (bookNum.length()!=ISBN_NUM) throw new ISBNException ("ISBN "+ bookNum + " must be 10 characters"); for (int i=0;i<bookNum.length();i++) { if (Character.isDigit(bookNum.charAt(i))) bookNum.CharAt[j]==book[i]; j++; if (book[9].isNotDigit()|| book[9]!="x" || book[9]!="X") throw new ISBNException ("ISBN " + bookNum + " must contain all digits" + "or 'X' in the last position");

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• Storing multiple discarded datas in a single variable using a string accumulator

  - by dan

  For an assignment for my intro to python course, we are to write a program that generates 100 sets of x,y coordinates. X must be a float between -100.0 and 100.0 inclusive, but not 0. Y is Y = ((1/x) * 3070) but if the absolute value of Y is greater than 100, both numbers must be discarded (BUT STORED) and another set generated. The results must be displayed in a table, and then after the table, the discarded results must be shown. The teacher said we should use a "string accumulator" to store the discarded data. This is what I have so far, and I'm stuck at storing the discarded data. # import random.py import random # import math.py import math # define main def main(): x = random.uniform(-100.0, 100.0) while x == 0: x = random.uniform(-100.0, 100.0) y = ((1/x) * 3070) while math.fabs(y) > 100: xDiscarded = yDiscarded = y = ((1/x) * 3070) As you can see, I run into the problem of when abs(y) 100, I'm not too sure how to store the discarded data and let it accumulate every time abs(y) 100. I'm cool with the data being stored as "351.2, 231.1, 152.2" I just don't know how to turn the variable into a string and store it. We haven't learned arrays yet so I can't do that. Any help would be much appreciated. Thanks!

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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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• 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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• 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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• How to make paging start from 1 instead of 0 in ASP.NET MVC

  - by ssx

  I used the paging example of the Nerddinner tutorial. But I also wanted to add page Numbers, somehting like that: <<< 1 2 3 4 5 6 The code below works if i start my paging from 0, but not from 1. How can I fix this ? Here is my code: PaginatedList.cs public class PaginatedList<T> : List<T> { public int PageIndex { get; private set; } public int PageSize { get; private set; } public int TotalCount { get; private set; } public int TotalPages { get; private set; } public PaginatedList(IQueryable<T> source, int pageIndex, int pageSize) { PageIndex = pageIndex; PageSize = pageSize; TotalCount = source.Count(); TotalPages = (int) Math.Ceiling(TotalCount / (double)PageSize); this.AddRange(source.Skip(PageIndex * PageSize).Take(PageSize)); } public bool HasPreviousPage { get { return (PageIndex > 0); } } public bool HasNextPage { get { return (PageIndex+1 < TotalPages); } } } UserController.cs public ActionResult List(int? page) { const int pageSize = 20; IUserRepository userRepository = new UserRepository(); IQueryable<User> listUsers = userRepository.GetAll(); PaginatedList<User> paginatedUsers = new PaginatedList<User>(listUsers, page ?? 0, pageSize); return View(paginatedUsers); } List.cshtml @if (Model.HasPreviousPage) { @Html.RouteLink(" Previous ", "PaginatedUsers", new { page = (Model.PageIndex - 1) }) } @for (int i = 1; i <= Model.TotalPages; i++) { @Html.RouteLink(@i.ToString(), "PaginatedUsers", new { page = (@i ) }) } @if (Model.HasNextPage) { @Html.RouteLink(" Next ", "PaginatedUsers", new { page = (Model.PageIndex + 1) }) }

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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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• 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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• Need help: input int from console and pass it into method in different class and do math

  - by christophe

  i'm a beginner, Need help, Please!!! I want to read optional number "a" from console and then store it in variable to use as passing to a different class (different .java file). and pint the sum separetely by optional inputting. How do i code the 2 classes? thanks /* * DemoApp.java */ public class DemoApp { public static void main(String[] args) { Scanner input = new Scanner(System.in); int a; System.out.println("Input one of the following 3 numbers: 100, 200, 300"); System.out.print("Enter: "); a = input.nextInt(); TestApplication testapp = new TestApplication(); testapp.test(a); } } /* * TestApplication.java * */ public class TestApplication { private int a; public void test(int a) { this.a = a; // TODO: where to get the "a"? (entered by users from console) System.out.println("The number_a was passed in: "+a); } protected void printNum() throws Exception { int num; switch (a) { case 100: num = num + 10; break; case 200: num = num + 20; break; case 300: num = num + 30; break; default: // TODO: unexpected number input. throw(); break; } System.out.println("I got a sum number"+num); } }

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