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• Using Relative Paths to Load Resources in Cocoa/C++

  - by moka

  I am currently working directly with Cocoa for the first time to built a screen saver. Now I came across a problem when trying to load resources from within the .saver bundle. I basically have a small C++ wrapper class to load .exr files using freeImage. This works as long as I use absoulte paths, but that's not very useful, is it? So, basically, I tried everything: putting the .exr file at the level of the .saver bundle itself, inside the bundles Resources folder, and so on. Then I simply tried to load the .exr like this, but without success: particleTex = [self loadExrTexture:@"ball.exr"]; I also tried making it go to the .saver bundles location like this: particleTex = [self loadExrTexture:@"../../../ball.exr"]; ...to maybe load the .exr from that location, but without success. I then came across this: NSString * path = [[NSBundle mainBundle] pathForResource:@"ball" ofType:@"exr"]; const char * pChar = [path UTF8String]; ...which seems to be a common way to find resources in Cocoa, but for some reason it's empty in my case. Any ideas about that? I really tried out anything that came to my mind without success so I would be glad about some input!

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• Using "from __future__ import division" in my program, but it isn't loaded with my program

  - by Sara Fauzia

  I wrote the following program in Python 2 to do Newton's method computations for my math problem set, and while it works perfectly, for reasons unbeknownst to me, when I initially load it in ipython with %run -i NewtonsMethodMultivariate.py, the Python 3 division is not imported. I know this because after I load my Python program, entering x**(3/4) gives "1". After manually importing the new division, then x**(3/4) remains x**(3/4), as expected. Why is this? # coding: utf-8 from __future__ import division from sympy import symbols, Matrix, zeros x, y = symbols('x y') X = Matrix([[x],[y]]) tol = 1e-3 def roots(h,a): def F(s): return h.subs({x: s[0,0], y: s[1,0]}) def D(s): return h.jacobian(X).subs({x: s[0,0], y: s[1,0]}) if F(a) == zeros(2)[:,0]: return a else: while (F(a)).norm() > tol: a = a - ((D(a))**(-1))*F(a) print a.evalf(10) I would use Python 3 to avoid this issue, but my Linux distribution only ships SymPy for Python 2. Thanks to the help anyone can provide. Also, in case anyone was wondering, I haven't yet generalized this script for nxn Jacobians, and only had to deal with 2x2 in my problem set. Additionally, I'm slicing the 2x2 zero matrix instead of using the command zeros(2,1) because SymPy 0.7.1, installed on my machine, complains that "zeros() takes exactly one argument", though the wiki suggests otherwise. Maybe this command is only for the git version.

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• how to call subactivity of another application android?

  - by Are

  Hi. To call main activity I saw componentName class in android. intent = new Intent(new ComponentName(packageNam,classname); if same is used in case of child activity, I got error , "is activity delcared in andorid manifest?" like error. how to call app1 child activity in app2 by using intent ? In app1 the activity is declared like this in manifest <activity android:name=".activity.MessageCompose" android:label="@string/app_name" android:enabled="false"> - <intent-filter> <action android:name="android.intent.action.VIEW" /> <action android:name="android.intent.action.SENDTO" /> <data android:scheme="mailto" /> <category android:name="android.intent.category.DEFAULT" /> <category android:name="android.intent.category.BROWSABLE" /> </intent-filter> - <intent-filter android:label="@string/app_name"> <action android:name="android.intent.action.SEND" /> <data android:mimeType="*/*" /> <category android:name="android.intent.category.DEFAULT" /> </intent-filter> - <intent-filter android:label="@string/app_name"> <action android:name="android.intent.action.SEND_MULTIPLE" /> <data android:mimeType="*/*" /> <category android:name="android.intent.category.DEFAULT" /> </intent-filter> </activity>

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• Most efficient way to LIMIT results in a JOIN?

  - by johnnietheblack

  I have a fairly simple one-to-many type join in a MySQL query. In this case, I'd like to LIMIT my results by the left table. For example, let's say I have an accounts table and a comments table, and I'd like to pull 100 rows from accounts and all the associated comments rows for each. Thy only way I can think to do this is with a sub-select in in the FROM clause instead of simply selecting FROM accounts. Here is my current idea: SELECT a.*, c.* FROM (SELECT * FROM accounts LIMIT 100) a LEFT JOIN `comments` c on c.account_id = a.id ORDER BY a.id However, whenever I need to do a sub-select of some sort, my intermediate level SQL knowledge feels like it's doing something wrong. Is there a more efficient, or faster, way to do this, or is this pretty good? By the way... This might be the absolute simplest way to do this, which I'm okay with as an answer. I'm simply trying to figure out if there IS another way to do this that could potentially compete with the above statement in terms of speed.

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• Forming triangles from points and relations

  - by SiN

  Hello, I want to generate triangles from points and optional relations between them. Not all points form triangles, but many of them do. In the initial structure, I've got a database with the following tables: Nodes(id, value) Relations(id, nodeA, nodeB, value) Triangles(id, relation1_id, relation2_id, relation3_id) In order to generate triangles from both nodes and relations table, I've used the following query: INSERT INTO Triangles SELECT t1.id, t2.id , t3.id, FROM Relations t1, Relations t2, Relations t3 WHERE t1.id < t2.id AND t3.id > t1.id AND ( t1.nodeA = t2.nodeA AND (t3.nodeA = t1.nodeB AND t3.nodeB = t2.nodeB OR t3.nodeA = t2.nodeB AND t3.nodeB = t1.nodeB) OR t1.nodeA = t2.nodeB AND (t3.nodeA = t1.nodeB AND t3.nodeB = t2.nodeA OR t3.nodeA = t2.nodeA AND t3.nodeB = t1.nodeB) ) It's working perfectly on small sized data. (~< 50 points) In some cases however, I've got around 100 points all related to each other which leads to thousands of relations. So when the expected number of triangles is in the hundreds of thousands, or even in the millions, the query might take several hours. My main problem is not in the select query, while I see it execute in Management Studio, the returned results slow. I received around 2000 rows per minute, which is not acceptable for my case. As a matter of fact, the size of operations is being added up exponentionally and that is terribly affecting the performance. I've tried doing it as a LINQ to object from my code, but the performance was even worse. I've also tried using SqlBulkCopy on a reader from C# on the result, also with no luck. So the question is... Any ideas or workarounds?

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• How long is the time frame between context switches on Windows?

  - by mattcodes

  Reading CLR via C# 2.0 (I dont have 3.0 with me at the moment) Is this still the case: If there is only one CPU in a computer, only one thread can run at any one time. Windows has to keep track of the thread objects, and every so often, Windows has to decide which thread to schedule next to go to the CPU. This is additional code that has to execute once every 20 milliseconds or so. When Windows makes a CPU stop executing one thread's code and start executing another thread's code, we call this a context switch. A context switch is fairly expensive because the operating system has to: So circa CLR via C# 2.0 lets say we are on Pentium 4 2.4ghz 1 core non-HT, XP. Every 20 milliseconds? Where a CLR thread or Java thread is mapped to an OS thread only a maximum of 50 threads per second may get a chance to to run? I've read that context switching is very fast in mircoseconds here on SO, but how often roughly (magnitude style guesses) will say a modest 5 year old server Windows 2003 Pentium Xeon single core give the OS the opportunity to context switch? 20ms in the right area? I dont need exact figures I just want to be sure that's in the right area, seems rather long to me.

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• Avoid using InetAddress - Getting a raw IP address in network byte order

  - by Mylo

  Hey, I am trying to use the MaxMind GeoLite Country database on the Google App Engine. However, I am having difficulty getting the Java API to work as it relies on the InetAddress class which is not available to use on the App Engine. However, I am not sure if there is a simple workaround as it appears it only uses the InetAddress class to determine the IP of a given hostname. In my case, the hostname is always an IP anyway. What I need is a way to convert an IP address represented as a String into a byte array of network byte order (which the addr.getAddress() method of the InetAddress class provides). This is the code the current API uses, I need to find a way of removing all references to InetAddress whilst ensuring it still works! Thanks for your time. /** * Returns the country the IP address is in. * * @param ipAddress String version of an IP address, i.e. "127.0.0.1" * @return the country the IP address is from. */ public Country getCountry(String ipAddress) { InetAddress addr; try { addr = InetAddress.getByName(ipAddress); } catch (UnknownHostException e) { return UNKNOWN_COUNTRY; } return getCountry(bytesToLong(addr.getAddress())); }

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• Batch script is not executed if chcp was called

  - by Andy

  Hello! I'm trying to delete some files with unicode characters in them with batch script (it's a requirement). So I run cmd and execute: > chcp 65001 Effectively setting codepage to UTF-8. And it works: D:\temp\1>dir Volume in drive D has no label. Volume Serial Number is 8C33-61BF Directory of D:\temp\1 02.02.2010 09:31 <DIR> . 02.02.2010 09:31 <DIR> .. 02.02.2010 09:32 508 1.txt 02.02.2010 09:28 12 delete.bat 02.02.2010 09:20 95 delete.cmd 02.02.2010 09:13 <DIR> Rún 02.02.2010 09:13 <DIR> ????? ??????? 3 File(s) 615 bytes 4 Dir(s) 11 576 438 784 bytes free D:\temp\1>rmdir Rún D:\temp\1>dir Volume in drive D has no label. Volume Serial Number is 8C33-61BF Directory of D:\temp\1 02.02.2010 09:56 <DIR> . 02.02.2010 09:56 <DIR> .. 02.02.2010 09:32 508 1.txt 02.02.2010 09:28 12 delete.bat 02.02.2010 09:20 95 delete.cmd 02.02.2010 09:13 <DIR> ????? ??????? 3 File(s) 615 bytes 3 Dir(s) 11 576 438 784 bytes free Then I put the same rmdir commands in batch script and save it in UTF-8 encoding. But when I run nothing happens, literally nothing: not even echo works from batch script in this case. Even saving script in OEM encoding does not help. So it seems that when I change codepage to UTF-8 in console, scripts just stop working. Does somebody know how to fix that?

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• There is a Default instance of form in VB.Net but not in C#, WHY?

  - by Shekhar_Pro

  I'm just curious to know that there is The (Name) property, which represents the name of the Form class.This property is used within the namespace to uniquely identify the class that the Form is an instance of and, in the case of Visual Basic, is used to access the default instance of the form. Now where this Default Instance come from, why can't C# have a equivalent method to this. Also for example to show a form in C# we do something like this: //Only method Form1 frm = new Form1(); frm.Show(); But in VB.Net we have both ways to do it: //'First common method (used slash because editor wouldn't format it properly) Form1.Show(); //'Second method Dim frm as New Form1(); frm.Show(); My question comes from this first method. What is this Form1, is it an instance of Form1 or the Form1 class itself. Now as i mentioned above the Form name is the Default instance in VB.Net. But we also know that Form1 is a class defined in Designer so how can the names be same for both the Instance and class name. If Form1 is Class then there is no (Static\Shared) method named Show(). So where does this method come from. And finally why C# can't have an equivalent of this. If there some mistake in my question Please let me know *I've checked this on stackoverflow, but couldn't find an answer to this.If you do find then please give a link to it.*

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• PHP Object Creation and Memory Usage

  - by JohnO

  A basic dummy class: class foo { var $bar = 0; function foo() {} function boo() {} } echo memory_get_usage(); echo "\n"; $foo = new foo(); echo memory_get_usage(); echo "\n"; unset($foo); echo memory_get_usage(); echo "\n"; $foo = null; echo memory_get_usage(); echo "\n"; Outputs: $ php test.php 353672 353792 353792 353792 Now, I know that PHP docs say that memory won't be freed until it is needed (hitting the ceiling). However, I wrote this up as a small test, because I've got a much longer task, using a much bigger object, with many instances of that object. And the memory just climbs, eventually running out and stopping execution. Even though these large objects do take up memory, since I destroy them after I'm done with each one (serially), it should not run out of memory (unless a single object exhausts the entire space for memory, which is not the case). Thoughts?

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• Can isdigit legitimately be locale dependent in C

  - by cdev

  In the section covering setlocale, the ANSI C standard states in a footnote that the only ctype.h functions whose behaviour is not affected by the current locale are isdigit and isxdigit. The Microsoft implementation of isdigit is locale dependent because, for example, in locales using code page 1250 isdigit only returns non-zero for characters in the range 0x30 ('0') - 0x39 ('9'), whereas in locales using code page 1252 isdigit also returns non-zero for the superscript digits 0xB2 ('²'), 0xB3 ('³') and 0xB9 ('¹'). Is Microsoft in violation of the C standard by making isdigit locale dependent? In this question I am primarily interested in C90, which Microsoft claims to conform to, rather than C99. Additional background: Microsoft's own documentation of setlocale incorrectly states that isdigit is unaffected by the LC_CTYPE part of the locale. The section of the C standard that covers the ctype.h functions contains some wording that I consider ambiguous: "The behavior of these functions is affected by the current locale. Those functions that have locale-specific aspects only when not in the "C" locale are noted below." I consider this ambiguous because it is unclear what it is trying to say about functions such as isdigit for which there are no notes about locale-specific aspects. It might be trying to say that such functions must be assumed to be locale dependent, in which case Microsoft's implementation of isdigit would be OK. (Except that the footnote I mentioned earlier seems to contradict this interpretation.)

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• RMagick transparent_color deprecated? What's the alternative?

  - by user315975

  I'm developing an app that does a fair amount of generating transparent pngs on the fly. These are used as overlays, to show areas of interest in a graphic, so they have to have transparent backgrounds. I am developing in Ruby on Rails, deploying on Heroku. What works fine in development is not working in production. I get this error when I call a drawing routine using RMagick: NotImplementedError (the `transparent_color=' method is not supported by ImageMagick 6.2.4): /usr/local/lib/ruby/gems/1.8/gems/rmagick-1.15.17/lib/RMagick.rb:1691:in `transparent_color=' I'm using RMagick version 2.12.1 on the development machine, but I'm not exactly certain how to discover the version of ImageMagick that it's running, so I'm not sure if this is a case of my local code being behind or ahead. I'm hoping behind, because perhaps then there'll be a replacement for this call. Does anyone know what the fix is here? What's required to generate a transparent background, if not the call I'm using? I can't find this in the documentation: in fact, it was on a third-party site that I found mention of this capability.

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• Parsing CSS by regex

  - by Ross

  I'm creating a CSS editor and am trying to create a regular expression that can get data from a CSS document. This regex works if I have one property but I can't get it to work for all properties. I'm using preg/perl syntax in PHP. Regex (?<selector>[A-Za-z]+[\s]*)[\s]*{[\s]*((?<properties>[A-Za-z0-9-_]+)[\s]*:[\s]*(?<values>[A-Za-z0-9#, ]+);[\s]*)*[\s]*} Test case body { background: #f00; font: 12px Arial; } Expected Outcome Array( [0] => Array( [0] => body { background: #f00; font: 12px Arial; } [selector] => Array( [0] => body ) [1] => Array( [0] => body ) [2] => font: 12px Arial; [properties] => Array( [0] => font ) [3] => Array( [0] => font ) [values] => Array( [0] => 12px Arial [1] => background: #f00 ) [4] => Array( [0] => 12px Arial [1] => background: #f00 ) ) ) Real Outcome Array( [0] => Array ( [0] => body { background: #f00; font: 12px Arial; } [selector] => body [1] => body [2] => font: 12px Arial; [properties] => font [3] => font [values] => 12px Arial [4] => 12px Arial ) ) Thanks in advance for any help - this has been confusing me all afternoon!

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• How to write these two queries for a simple data warehouse, using ANSI SQL?

  - by morpheous

  I am writing a simple data warehouse that will allow me to query the table to observe periodic (say weekly) changes in data, as well as changes in the change of the data (e.g. week to week change in the weekly sale amount). For the purposes of simplicity, I will present very simplified (almost trivialized) versions of the tables I am using here. The sales data table is a view and has the following structure: CREATE TABLE sales_data ( sales_time date NOT NULL, sales_amt double NOT NULL ) For the purpose of this question. I have left out other fields you would expect to see - like product_id, sales_person_id etc, etc, as they have no direct relevance to this question. AFAICT, the only fields that will be used in the query are the sales_time and the sales_amt fields (unless I am mistaken). I also have a date dimension table with the following structure: CREATE TABLE date_dimension ( id integer NOT NULL, datestamp date NOT NULL, day_part integer NOT NULL, week_part integer NOT NULL, month_part integer NOT NULL, qtr_part integer NOT NULL, year_part integer NOT NULL, ); which partition dates into reporting ranges. I need to write queries that will allow me to do the following: Return the change in week on week sales_amt for a specified period. For example the change between sales today and sales N days ago - where N is a positive integer (N == 7 in this case). Return the change in change of sales_amt for a specified period. For in (1). we calculated the week on week change. Now we want to know how that change is differs from the (week on week) change calculated last week. I am stuck however at this point, as SQL is my weakest skill. I would be grateful if an SQL master can explain how I can write these queries in a DB agnostic way (i.e. using ANSI SQL).

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• Viewing recently edited etherpads (note new 'etherpad' tag for open sourced etherpad code!)

  - by dreeves

  Prescript: The amazing etherpad was recently open sourced. Get it here: http://code.google.com/p/etherpad. This is the first question that I know of on StackOverflow about the etherpad code. If you're part of the etherpad open source community, you might want to subscribe to the RSS feed for questions tagged 'etherpad' just in case this catches on! My actual question, which assumes you have etherpad installed on your own server: First, here's a query to view recently edited pads: SELECT id,lastWriteTime,creationTime,headRev FROM PAD_SQLMETA ORDER BY lastWriteTime, headRev; Or, if you want to run it from a unix prompt: mysql -u root -pPASSWD etherpad -e "select id,lastWriteTime,creationTime,headRev from PAD_SQLMETA order by lastWriteTime, headRev" That's handy, however lastWriteTime actually gets updated every time someone so much as views a pad in their browser. I'd rather sort the pads by when they were actually last edited. There's probably a fancy SQL query involving a join with another table that would show actual last edit time. Does anyone know what that is? Alternatively, you could have a script that notices when headRev changes but that doesn't seem like the cleanest way to do it.

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• Best way of showing more results with javascript/css

  - by Ricardo Neves

  I'm developing a website and i'm having troubles showing the search results to the user the way I want. Basically, after the user search, the page makes a couple of ajax requests and as soon as a response arrive it appends the info to a specific element on my page. Each results is shown as a line... The problem is that in most case there are going to be more than 1000 results and this would make the page have a large scroll. My idea was to show only the first 15 results and when the user clicks "show more" the element would expand and show the next 15 results and so on... This would be easier to do if the website wasn't responsive, but because it is I can't find the proper way of implementing what I want without lowering the website perfomance. I have "2 ideas": The first is by using something like #element .div:nth-child(-n+15) on my css and figure a way of changing the "15" to how much results I want to show... I don't know if this can be done. Is it possible to call css rules with parameters? Maybe with less css? The second option is probably a bad option if i don't want to lower the website performance. Using javascript I would check if there is a specific css class(like .show-15 .show30 .show45) and add that class to my element and if it don't exist, create it somehow.. Any help would be appreciated.

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• OnClickListener onClick=true and selector

  - by azerto00

  I have not found any answer for my problem, so I need your help ... I have an LinearLayout which I want to be clickable in order to lunch another activity. So I implement an onClickListener to it. I created an selector for this LinearLayout in order that what someone click on it, the background change. I just don't understand that : If my LinearLayout doesn't have android:clickable="true" in the xml, I'm able to click on it and get what I want but the selector doesn't work. If I remove this line, it is the opposite .. the selector work but not the onClick event. So, can anyone can explain me why ? Just in case, here is my the content of my selector file : <selector xmlns:android="http://schemas.android.com/apk/res/android"> <item android:drawable="@drawable/btn_restaurants_background_state_pressed" android:state_pressed="true"></item> <item android:drawable="@drawable/btn_restaurants_background_state_pressed" android:state_focused="true"></item> <item android:drawable="@drawable/btn_restaurants_background_state_pressed" android:state_selected="true"></item> <item android:drawable="@drawable/btn_restaurants_background_state_normal"></item> </selector> Thanks you in advance

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• Gearman client doBackground always returns GEARMAN_TIMEOUT

  - by Ascherer

  So, ive got a simple gearman system running right now, with a worker running. The worker basically just takes the payload (a random number in this case, and is supposed to echo it back to the screen. Literally an echo, not returning to the client. The client sends the random number. Im trying to do a $client->doBackground( 'post', 65482, md5(uniqid())); but its coming back with a 47 error (GEARMAN_TIMEOUT) every time. getErrNo() returns 0, error() returns something about GEARMAN_TIMEOUT However, when i change it to just $client->do(blah, blah, blah), it works just fine. I've even occasionally seen it where the worker still echo's the number, even after getting the timeout error... public function execute() { $method = 'do'; if( !$this->getBlock() ) { $method .= ( $this->getPriority() == 'Normal' ? '' : $this->getPriority() ) . 'Background'; } else { $method .= $this->getPriority(); } echo "Method: $method \t Worker: {$this->getName()} \t Payload: {$this->getPayload()} \t Hash: {$this->getHash()}\n"; $this->setResult( $this->getClient() ->$method( $this->getName(), $this->getPayload(), $this->getHash() ) ); if( $this->getClient()->returnCode() != GEARMAN_SUCCESS ) { echo "Code: " . $this->getClient()->returnCode() . "\t" . GEARMAN_TIMEOUT . "\n"; } }

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• How do I close a file after catching an IOException in java?

  - by DimDom

  All, I am trying to ensure that a file I have open with BufferedReader is closed when I catch an IOException, but it appears as if my BufferedReader object is out of scope in the catch block. public static ArrayList readFiletoArrayList(String fileName, ArrayList fileArrayList) { fileArrayList.removeAll(fileArrayList); try { //open the file for reading BufferedReader fileIn = new BufferedReader(new FileReader(fileName)); // add line by line to array list, until end of file is reached // when buffered reader returns null (todo). while(true){ fileArrayList.add(fileIn.readLine()); } }catch(IOException e){ fileArrayList.removeAll(fileArrayList); fileIn.close(); return fileArrayList; //returned empty. Dealt with in calling code. } } Netbeans complains that it "cannot find symbol fileIn" in the catch block, but I want to ensure that in the case of an IOException that the Reader gets closed. How can I do that without the ugliness of a second try/catch construct around the first? Any tips or pointers as to best practise in this situation is appreciated,

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• Sending emails with CodeIgniter in a local XAMPP server

  - by KeyStroke

  Hi, I'm trying to send emails through localhost (XAMPP Windows 1.7.3 installation), but I've been trying for hours with no success. This is the last code I tried: $config = Array( 'protocol' => 'smtp', 'smtp_host' => 'ssl://smtp.gmail.com', 'smtp_port' => 465, 'smtp_user' => '[email protected]', 'smtp_pass' => 'mypassword', ); $this->load->library('email', $config); $this->email->set_newline("\r\n"); $this->email->from('[email protected]', 'My Name'); $this->email->to('[email protected]'); $this->email->subject('Email Test'); $this->email->message('Testing the email class.'); if($this->email->send()) { echo 'Your email was sent.'; } else { show_error($this->email->print_debugger()); } Whenever I tried to load this the page shows that it's loading but nothing happens. Is there anything I need to setup in my server to insure email delivery? I messed with php.ini and sendmail's config a bit with no luck. And openSSL isn't available in case that matters. Any idea what's wrong?

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• Random number generation in MVC applications

  - by SlimShaggy

  What is the correct way of generating random numbers in an ASP.NET MVC application if I need exactly one number per request? According to MSDN, in order to get randomness of sufficient quality, it is necessary to generate multiple numbers using a single System.Random object, created once. Since a new instance of a controller class is created for each request in MVC, I cannot use a private field initialized in the controller's constructor for the Random object. So in what part of the MVC app should I create and store the Random object? Currently I store it in a static field of the controller class and lazily initialize it in the action method that uses it: public class HomeController : Controller { ... private static Random random; ... public ActionResult Download() { ... if (random == null) random = new Random(); ... } } Since the "random" field can be accessed by multiple instances of the controller class, is it possible for its value to become corrupted if two instances attempt to initialize it simultaneously? And one more question: I know that the lifetime of statics is the lifetime of the application, but in case of an MVC app what is it? Is it from IIS startup till IIS shutdown?

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• I need to recover an instance of an activity

  - by Bilthon

  Well.. the title is pretty descriptive, I have a bunch of tab activities (which I implemented myself, didn't want to use the tabviews with activities inside them), so It's basically 5 activities calling each other every time the user clicks on the tabs displayed as a row of LinearLayouts at the bottom of the screen. The thing is that the way I do it now, everytime the user jumps from one activity to another, a new activity is created and launched. Of course, I can see I'm wasting resources this way. So what I would like to do is to create every activity only once; and then if the user wants to go back to the previous (or any one that was already created and is probably paused) just check on some kind of list or array to see if the activity can be recovered and only in the case it can't; to lauch a new one. My question is, how can I check this? should I save the intents? and how to recover the activities afterwards? I'm kind of new with java. Greetings Nelson R. Perez

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• "Invalid use of Null" when using Str() with a Null Recordset field, but Str(Null) works fine

  - by Mike Spross

  I'm banging my head against the wall on this one. I was looking at some old database reporting code written in VB6 and case across this line (the code is moving data from a "source" database into a reporting database): rsTarget!VehYear = Trim(Str(rsSource!VehYear)) When rsSource!VehYear is Null, the above line generates an "Invalid use of Null" run-time error. If I break on the above line and type the following in the Immediate pane: ?rsSource!VehYear It outputs Null. Fine, that makes sense. Next, I try to reproduce the error: ?Str(rsSource!VehYear) I get an "Invalid use of Null" error. However, if I type the following into the Immediate window: ?Str(Null) I don't get an error. It simply outputs Null. If I repeat the same experiment with Trim() instead of Str(), everything works fine. ?Trim(rsSource!VehYear) returns Null, as does ?Trim(Null). No run-time errors. So, my question is, how can Str(rsSource!VehYear) possibly throw an "Invalid use of Null" error when Str(Null) does not, when I know that rsSource!VehYear is equal to Null?

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• C++ Loop - Need variable to accumulate sum

  - by user1780064

  I'm writing a program to ask the user to enter a value between 5 and 21 (inclusive). If the number entered is not in this range, it prints, "Please try again". If the number is within the range, I need to take that number, and print the sum of all the numbers from 1 to the value entered. So if the user entered "7", the sum would be "28". I successfully wrote the first loop, in the case of the number not being within the range, but cannot figure out how to run the second loop- whether to use a while, do-while, or for loop. Please advise. #include <iostream> int main () { int uservalue; int count; int sum; //Prompt user for input do { cout << "Enter a value from 5 to 21: "; cin >> uservalue; if (uservalue < 5 || uservalue > 21) cout << "Value out of range. Try again..." << endl; } while (uservalue < 5 || uservalue > 21); cout << endl; //Loop to accumulate sum for (count = 1, count < uservalue, count++;) { sum = uservalue + count; if (uservalue <= 5 || uservalue <= 21) cout << the sum is " << sum << endl; } return 0; }

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• Basic HTML Internal Link not working in IE8

  - by Eamonn

  This one has me scratching my head. I have a page with several internal links bringing the user down the page to further content. Beneath various sections there are further internal links bringing the user back to the top. This works fine in all browsers apart from IE8 (actual IE8 - not IE9 in IE8 mode) where they work go down, but not coming back up! Examples: <a href="page.php?v=35&amp;u=admin-videos#a">A &ndash; General</a> .... //travelling DOWN the page <h3><strong>A &ndash; General<a name="a"></a></strong></h3> <a name="top"></a> .... //travelling back up <a href="page.php?v=35&amp;u=admin-videos#top">Back to top.</a> I've tried filling the 'top' anchor with &nbsp; but that hasn't changed it. Any ideas? Actual use case: http://databizsolutions.ie/contents/page.php?v=35&u=admin-videos

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