Search Results

Search found 7793 results on 312 pages for 'sample'.

Page 231/312 | < Previous Page | 227 228 229 230 231 232 233 234 235 236 237 238  | Next Page >

  • Detecting a Dispose() from an exception inside using block

    - by Augusto Radtke
    I have the following code in my application: using (var database = new Database()) { var poll = // Some database query code. foreach (Question question in poll.Questions) { foreach (Answer answer in question.Answers) { database.Remove(answer); } // This is a sample line that simulate an error. throw new Exception("deu pau"); database.Remove(question); } database.Remove(poll); } This code triggers the Database class Dispose() method as usual, and this method automatically commits the transaction to the database, but this leaves my database in an inconsistent state as the answers are erased but the question and the poll are not. There is any way that I can detect in the Dispose() method that it being called because of an exception instead of regular end of the closing block, so I can automate the rollback? I don´t want to manually add a try ... catch block, my objective is to use the using block as a logical safe transaction manager, so it commits to the database if the execution was clean or rollbacks if any exception occured. Do you have some thoughts on that?

    Read the article

  • m2crypto aes-256-cbc not working against encoded openssl files.

    - by Gary
    $ echo 'this is text' > text.1 $ openssl enc -aes-256-cbc -a -k "thisisapassword" -in text.1 -out text.enc $ openssl enc -d -aes-256-cbc -a -k "thisisapassword" -in text.enc -out text.2 $ cat text.2 this is text I can do this with openssl. Now, how do I do the same in m2crypto. Documentation is lacking this. I looked at the snv test cases, still nothing there. I found one sample, http://passingcuriosity.com/2009/aes-encryption-in-python-with-m2crypto/ (changed to aes_256_cbc), and it will encrypted/descrypt it's own strings, but it cannot decrypt anything made with openssl, and anything it encrypts isn't decryptable from openssl. I need to be able enc/dec with aes-256-cbc as have many files already encrypted with this and we have many other systems in place that also handle the aes-256-cbc output just fine. We use password phrases only, with no IV. So setting the IV to \0 * 16 makes sense, but I'm not sure if this is also part of the problem. Anyone have any working samples of doing AES 256 that is compatible with m2crypto? I will also be trying some additional libraries and seeing if they work any better.

    Read the article

  • DSP - Filtering frequencies using DFT

    - by Trap
    I'm trying to implement a DFT-based 8-band equalizer for the sole purpose of learning. To prove that my DFT implementation works I fed an audio signal, analyzed it and then resynthesized it again with no modifications made to the frequency spectrum. So far so good. I'm using the so-called 'standard way of calculating the DFT' which is by correlation. This method calculates the real and imaginary parts both N/2 + 1 samples in length. To attenuate a frequency I'm just doing: float atnFactor = 0.6; Re[k] *= atnFactor; Im[k] *= atnFactor; where 'k' is an index in the range 0 to N/2, but what I get after resynthesis is a slighty distorted signal, especially at low frequencies. The input signal sample rate is 44.1 khz and since I just want a 8-band equalizer I'm feeding the DFT 16 samples at a time so I have 8 frequency bins to play with. Can someone show me what I'm doing wrong? I tried to find info on this subject on the internet but couldn't find any. Thanks in advance.

    Read the article

  • Pthread Queue System

    - by Wallace
    Hi. I'm working on my assignment on pthreads. I'm new and never touched on pthreads before. Is there any sample codes or resources out there that anyone of you have, that might aid me in my assignment? Here are my assignment details. A pthread program about queue system: Write a C/C++ Pthread program for a Dental clinic’s queuing system that declares an array of integers of size N, where N is the maximum number of queue for the day. The pthread program uses two threads. Whenever there is a new dental appointment, the first thread (the creator) puts the queue numbers in the array, one after the other. The second thread (the remover) removes the queue numbers from the array whenever the dentist has seen the patient. This is done in a FIFO fashion (First In First Out). The algorithm of the creator is as follows: • If the array is not full then put a new number in it (the numbers start at 1 and are incremented by one each time, so the creator create queue number 1, 2, 3 etc.) • sleep for 1 to 10 seconds, randomly • repeat The algorithm of the remover is as follows: • If the array is not empty then remove its smallest queue number • sleep for 1 to 10 seconds, randomly • repeat You should use mutex locks to protect things that must be protected. Each thread should print on the screen what it is doing (eg: "number 13 is added into the queue", "number 7 is removed from the queue", etc.). The program should run forever. Any help will be appreciated. Thanks.

    Read the article

  • Reading a large file into Perl array of arrays and manipulating the output for different purposes

    - by Brian D.
    Hello, I am relatively new to Perl and have only used it for converting small files into different formats and feeding data between programs. Now, I need to step it up a little. I have a file of DNA data that is 5,905 lines long, with 32 fields per line. The fields are not delimited by anything and vary in length within the line, but each field is the same size on all 5905 lines. I need each line fed into a separate array from the file, and each field within the line stored as its own variable. I am having no problems storing one line, but I am having difficulties storing each line successively through the entire file. This is how I separate the first line of the full array into individual variables: my $SampleID = substr("@HorseArray", 0, 7); my $PopulationID = substr("@HorseArray", 9, 4); my $Allele1A = substr("@HorseArray", 14, 3); my $Allele1B = substr("@HorseArray", 17, 3); my $Allele2A = substr("@HorseArray", 21, 3); my $Allele2B = substr("@HorseArray", 24, 3); ...etc. My issues are: 1) I need to store each of the 5905 lines as a separate array. 2) I need to be able to reference each line based on the sample ID, or a group of lines based on population ID and sort them. I can sort and manipulate the data fine once it is defined in variables, I am just having trouble constructing a multidimensional array with each of these fields so I can reference each line at will. Any help or direction is much appreciated. I've poured over the Q&A sections on here, but have not found the answer to my questions yet. Thanks!! -Brian

    Read the article

  • Serializing a part of object graph

    - by Felix
    Hi all, I have a problem regarding Java custom serialization. I have a graph of objects and want to configure where to stop when I serialize a root object from client to server. Let's make it a bit concrete, clear by giving a sample scenario. I have Classes of type Company Employee (abstract) Manager extends Employee Secretary extends Employee Analyst extends Employee Project Here are the relations: Company(1)---(n)Employee Manager(1)---(n)Project Analyst(1)---(n)Project Imagine, I'm on the client side and I want to create a new company, assign it 10 employees (new or some existing) and send this new company to the server. What I expect in this scenario is to serialize the company and all bounding employees to the server side, because I'll save the relations on the database. So far no problem, since the default Java serialization mechanism serializes the whole object graph, excluding the field which are static or transient. My goal is about the following scenario. Imagine, I loaded a company and its 1000 employees from the server to the client side. Now I only want to rename the company's name (or some other field, that directly belongs to the company) and update this record. This time, I want to send only the company object to the server side and not the whole list of employees (I just update the name, the employees are in this use case irrelevant). My aim also includes the configurability of saying, transfer the company AND the employees but not the Project-Relations, you must stop there. Do you know any possibility of achieving this in a generic way, without implementing the writeObject, readObject for every single Entity-Object? What would be your suggestions? I would really appreciate your answers. I'm open to any ideas and am ready to answer your questions in case something is not clear.

    Read the article

  • Correct use of setEmtpyView in AdapterView

    - by Sebi
    I'm really having trouble using the setEmptyView method. I tried it to implement it in GridView and ListView, but both of them didnt work. Here a sample codeblock: networkGames = (GridView) baseLayer.findViewById(R.id.all_game_grid_network); networkGames.setBackgroundResource(R.drawable.game_border); networkGames.setSelector(R.drawable.game_active_border); networkGames.setOnItemClickListener(new NetworkGameListener()); networkGames.setEmptyView(View.inflate(baseLayer, R.drawable.no_network_games, null)); networkGames.setAdapter(new NetworkAdapter()); The network adapter contains no items: private class NetworkAdapter extends BaseAdapter { /* (non-Javadoc) * @see android.widget.Adapter#getCount() */ @Override public int getCount() { return 0; } /* (non-Javadoc) * @see android.widget.Adapter#getItem(int) */ @Override public Object getItem(int position) { return null; } /* (non-Javadoc) * @see android.widget.Adapter#getItemId(int) */ @Override public long getItemId(int position) { return 0; } /* (non-Javadoc) * @see android.widget.Adapter#getView(int, android.view.View, android.view.ViewGroup) */ @Override public View getView(int position, View convertView, ViewGroup parent) { return null; } } I also tried to call networkGames.setAdapter(null), but this doesnt work either. My emtpyView looks like this: <LinearLayout android:id="@+id/LinearLayout01" android:layout_width="fill_parent" android:layout_height="fill_parent" xmlns:android="http://schemas.android.com/apk/res/android"> <TextView android:text="There are currently no network games available. Start a new one." android:id="@+id/TextView01" android:layout_width="fill_parent" android:layout_height="fill_parent" android:gravity="center"> </TextView> </LinearLayout> I really don't know what I'm doing wrong. I also read various tutorials, but none of them metnioned any problems.

    Read the article

  • Beyond the @Produces annotation, how does Jersey (JAX-RS) know to treat a POJO as a specific mime ty

    - by hal10001
    I see a lot of examples for Jersey that look something like this: public class ItemResource { @GET @Path("/items") @Produces({"text/xml", "application/json"}) public List<Item> getItems() { List<Item> items = new ArrayList<Item>(); Item item = new Item(); item.setItemName("My Item Name!"); items.add(item); return items; } } But then I have trouble dissecting Item, and how Jersey knows how to translate an Item to either XML or JSON. I've seen very basic examples that just return a String of constructed HTML or XML, which makes more sense to me, but I'm missing the next step. I looked at the samples, and one of them stood out (the json-from-jaxb sample), since the object was marked with these types of annotations: @XmlAccessorType(XmlAccessType.FIELD) @XmlType(name = "", propOrder = { "flight" }) @XmlRootElement(name = "flights") I'm looking for tutorials that cover this "translation" step-by-step, or an explanation here of how to translate a POJO to output as a specific mime type. Thanks!

    Read the article

  • Trying to 'Make' CUDA SDK, ld cannot find library, ldconfig says it can.

    - by Andrew Bolster
    I know there are many other questions similar to this one, but none of the solutions posited there are working for me Basically, making the SDK sample files, i get /usr/bin/ld: cannot find -lcuda which would be an easy enough 'find the library and throw it to ldconfig', except ldconfig already says it has it... $ sudo ldconfig -v | grep cuda /usr/local/cuda/lib64: libcudartemu.so.3 -> libcudartemu.so.3.0.14 libcudart.so.3 -> libcudart.so.3.0.14 /usr/local/cuda/lib: libcudartemu.so.3 -> libcudartemu.so.3.0.14 libcudart.so.3 -> libcudart.so.3.0.14 libcuda.so.1 -> libcuda.so.195.36.15 libcuda.so.1 -> libcuda.so.195.36.15 libicudata.so.42 -> libicudata.so.42.1 And I checked, there is a symlink libcuda.so -> libcuda.so.1 but I'm still confused as to why libcuda.so -> ... doesnt show up I must be missing something really obvious. Any ideas?

    Read the article

  • Why is curl in Ruby slower than command-line curl?

    - by Stiivi
    I am trying to download more than 1m pages (URLs ending by a sequence ID). I have implemented kind of multi-purpose download manager with configurable number of download threads and one processing thread. The downloader downloads files in batches: curl = Curl::Easy.new batch_urls.each { |url_info| curl.url = url_info[:url] curl.perform file = File.new(url_info[:file], "wb") file << curl.body_str file.close # ... some other stuff } I have tried to download 8000 pages sample. When using the code above, I get 1000 in 2 minutes. When I write all URLs into a file and do in shell: cat list | xargs curl I gen all 8000 pages in two minutes. Thing is, I need it to have it in ruby code, because there is other monitoring and processing code. I have tried: Curl::Multi - it is somehow faster, but misses 50-90% of files (does not download them and gives no reason/code) multiple threads with Curl::Easy - around the same speed as single threaded Why is reused Curl::Easy slower than subsequent command line curl calls and how can I make it faster? Or what I am doing wrong? I would prefer to fix my download manager code than to make downloading for this case in a different way. Before this, I was calling command-line wget which I provided with a file with list of URLs. Howerver, not all errors were handled, also it was not possible to specify output file for each URL separately when using URL list. Now it seems to me that the best way would be to use multiple threads with system call to 'curl' command. But why when I can use directly Curl in Ruby? Code for the download manager is here, if it might help: Download Manager (I have played with timeouts, from not-setting it to various values, it did not seem help) Any hints appreciated.

    Read the article

  • ANTLR Tree Grammar and StringTemplate Code Translation

    - by Behrooz Nobakht
    I am working on a code translation project with a sample ANTLR tree grammar as: start: ^(PROGRAM declaration+) -> program_decl_tmpl(); declaration: class_decl | interface_decl; class_decl: ^(CLASS ^(ID CLASS_IDENTIFIER)) -> class_decl_tmpl(cid={$CLASS_IDENTIFIER.text}); The group template file for it looks like: group My; program_decl_tmpl() ::= << *WHAT?* >> class_decl_tmpl(cid) ::= << public class <cid> {} >> Based on this, I have these questions: Everything works fine apart from that what I should express in WHAT? to say that a program is simply a list of class declarations to get the final generated output? Is this approach averagely suitable for not so a high-level language? I have also studied ANTLR Code Translation with String Templates, but it seems that this approach takes much advantage of interleaving code in tree grammar. Is it also possible to do it as much as possible just in String Templates?

    Read the article

  • Filter subform using combobox

    - by TT1611
    This has taken me nearly 2 weeks and I dont know what else to do. I have a main form (UserSearch) that has a subform (TestUserSub). The associated table for both forms is tblusers. very simple; on the main form (UserSearch) I have a comboboxes associated with the fields in the tblusers eg cmbid, cmbname, cmbdept and so on. All I want, is for a user to make a selection from any of these comboboxes and for the associated fields to display in the subform (TestUserSub). I have tried several different versions of code in the afterupdate event in a couple of the comboboxes and nothing is happening in the subform or in other instances I get error message. One example i have tried is filtering running an SQL command Private Sub cmbid_AfterUpdate() Dim strSQL As String If IsNull(Me.cmbaccess) Then Me.RecordSource = "tblusers" Else strSQL = "SELECT tblUsers.[Team Member_ID] FROM tblUsers " & _ "WHERE (((tblUsers.[Team Member_ID])= " & [form_testusersub].[txtid2]))& ";" Me.RecordSource = strSQL End If End Sub The above didnt work..Can someone please help me with this. I have a sample database that i have been working off and by some very strange way, they have managed to do this same thing without calling any code. Is this possible?

    Read the article

  • PHP Switch and Login

    - by Steve Rivera
    I'm fairly new with PHP and I am messing around with a login/registration system. I setup my sample website using a PHP-SWITCH script I found a while back: <?php switch($_GET['id']) { default: include('home.php'); /* LOGIN PAGES */ break; case "register_form": include ('includes/user_system/register_form.php'); } ? On the registration page the form links to my "register.php" which checks the validity of the form and to check for any blank fields and so on. "register.php" is supposed to refresh the page and add a reason to what the user did wrong when submitting the form. On my "register_form.php" page, which holds the actual form. This field is hidden until the user makes a mistake. <?php if (isset($reg_error)) { ?> , please try again. My "register.php" checks the form for all the errors. Here's the bit of code that will refresh the page with the reason for the error: // Check if any of the fields are missing if (empty($_POST['username']) || empty($_POST['password']) || empty($_POST['confirmpass'])) { // Reshow the form with an error $reg_error = 'One or more fields missing'; include 'register_form.php'; Now after I submit the form without any fields filled out I get the error code, but it refreshes to the actual "register_form.php". The problem with this is that because of my PHP-SWITCH script (helps me manage the site a lot easier) I don't have any formatting on that page. The actual URL to my "register_form.php" would be: "index.php?id=register_form.php". Now I have tried several different things such as changing it to: include 'index.php?id=register_form.php' And also changing it to: header(location:index.php?id=register_form.php') Unfortunately all this does is refresh the page without the reason for the error. I know this can be easily solved by just adding a Javascript Validator but I'd like to know if it is possible to refresh the page with the error using either "include" or "header()" while having a PHP-SWITCH script on the website.

    Read the article

  • Problem in loading chart on the view in asp.net mvc?

    - by mary
    hello, I am working on the chart project in asp.net mvc. i used followinf code to genrate the chart on the controller. Chart chart1 = new Chart(); chart1.Height = 296; chart1.Width = 412; chart1.ImageType = ChartImageType.Png; Title title = chart1.Titles.Add("Main"); Series series1 = chart1.Series.Add("series1"); chart1.Series["series1"].Points.DataBindXY(xvalues, yvalues); chart1.Series["series1"].ChartType = SeriesChartType.Column ; ChartArea chartArea = chart1.ChartAreas.Add("Default"); chartArea.Area3DStyle.Enable3D = false ; MemoryStream ms = new MemoryStream(); chart1.SaveImage(ms); return File(ms.GetBuffer(), @"image/png"); and on the view page i am calling it as img src="/Home/SampleChart" alt="Sample Chart" when i am running it on local pc its working fine but when i deployed it on server then chart is not displaying instated alernate text is showing. and its not working on another pc also. plz if anyone can know the reson tell me. thank you.

    Read the article

  • Display a tree dijit using zend framework

    - by churris43
    I am trying to display a tree of categories and subcategories by using dijits with zend framework. Haven't been able to find a good example. This is what I've got: Basically I got the following code as my action: class SubcategoriesController extends Zend_Controller_Action{ ..... public function loadtreeAction() { Zend_Dojo::enableView($this->view); Zend_Layout::getMvcInstance()->disableLayout(); //Creating a sample tree of categories and subcategories $a["cat1"]["id"] = "id1"; $a["cat1"]["name"] = "Category1"; $a["cat1"]["type"] = "category"; $subcat1 = array("id" => "Subcat1","name" => "Subcategory1" , "type" => "subcategory"); $subcat2 = array("id" => "Subcat12","name" => "Subcategory12" , "type" => "subcategory"); $a["cat1"]["children"] = array($subcat1,$subcat2); $treeObj = new Zend_Dojo_Data('id', $a); $treeObj->setLabel('name'); $this->view->tree = $treeObj->toJson(); } .... } And on my view: <?php $this->dojo()->requireModule('dojo.data.ItemFileReadStore'); $this->dojo()->requireModule('dijit.Tree'); $this->dojo()->requireModule('dojo.parser'); ?> <div dojoType="dojo.data.ItemFileReadStore" url="/Subcategories/loadtree" jsId="store"></div> <div dojoType="dijit.tree.ForestStoreModel" jsId="treeModel" store="store" rootId="root" rootLabel="List of Categories" childrenAttrs="children" query="{type:'category'}"></div> <div dojoType="dijit.Tree" model="treeModel" labelAttrs="ListOfCategories"></div> It doesn't even seem to try to load the tree at all. Any help is appreciated

    Read the article

  • Why do child elements cause 'dropleave' to be called (drag-n-drop file upload)?

    - by tundoopani
    I have a HTML5 drag-n-drop script that allows users to drop files in #droparea. The #droparea div has child elements that are also div elements. <div id="droparea"> <div id="showif_no_dragover">Drag files here!</div> <div id="showif_dragover">Drop the files!</div> </div> The associated javascript/jquery is: var droptarget = "#droparea"; $(droptarget).live('dragenter', dragEnter); $(droptarget).live('dragleave', dragExit); $(droptarget).live('dragover', nothing); $(droptarget).live('drop', dropGo); (Side question: should I use .live(), .on() or .bind() here?) I have created a sample jsFiddle with some additional code here: http://jsfiddle.net/PwFr9/3/ If you look at the console, you will notice that as you drag a file within #droparea, dragenter() and dragleave() are called multiple times, even though the drag is still inside #droparea. If you remove the child elements (#child1 and #child2), the problem is gone because the child elements are gone. How can I keep the child elements and prevent them from messing up the drag events? I have searched Stackoverflow and Google for hours without much help. I found this questions here at Stackoverflow: How to keep child elements from interfering with HTML5 dragover and drop events? I don't know why it works, though. I have tried placing 2 div elements on top of each other (via CSS positioning). The top-most div has the drag events attached whereas the bottom-most div has the child elements. I do not like this approach because it doesn't work with the rest of my page and does not allow mouse-click interaction with the bottom-most div. Any help is appreciated! Thank you in advance. Regards, tundoo

    Read the article

  • How can I get the mapi system stub dll to pass extended mapi calls to my dll?

    - by Bogatyr
    For various reasons (questioning the reasons is not helpful to me), I'd like to implement my own extended mapi dll for windows xp. I have a skeleton dll now, just a few entrypoints exist for testing, but the system mapi stub (c:\windows\system32\mapi32.dll, I've checked that it's identical to mapistub.dll) will not pass through calls to my dll, while it happily passes the same calls through to MS Outlook's msmapi32.dll, (MAPIInitialize, MAPILoginEx are two such calls). There's some secret handshake between the stub and the extended mapi dll wherein the stub checks that "yup, it's an extended mapi dll": maybe it's the presence of some additional entrypoints I haven't implemented yet, maybe it's the return value from some function, I don't know. I've tried tracing a sample app I wrote that calls MAPIInitialize with STraceNT and ProcessMonitor but that didn't show anything obvious. Tracing has shown that indeed the stub loads my dll, but then finds the secret sauce is missing apparently, and returns an error code instead of calling my dll's function. What more could be needed for calling MAPIInitialize than the presence of MAPIInitialize in my dll's exports table? GetProcAddress says it's there. What I'd like to know is how to minimally extend my skeleton extended mapi dll so that the stub mapi dll will pass through extended mapi calls to my dll. What's the secret sauce? I'd rather not spend a painful week in msvc reverse engineering the stub behavior.

    Read the article

  • Linq 2 SQL Store inherited classes - not mapped to tables in the database

    - by user348672
    Hi. I'm trying to introduce the Linq2SQL technique into the project and have encountered the following issue: I've created ORM classes based on the Northwind database. In some other application I create several classes derived from the Linq2SQL classes. I'm able to add such a class to EntitySet but the application fails to submit changes. Is there any way around this? Sample code(MyClass is derived from the Order): DataClasses1DataContext northwind = new DataClasses1DataContext(); Product chai = northwind.Products.Single(p => p.ProductName == "Chai"); Product tofu = northwind.Products.Single(p => p.ProductName == "Tofu"); Order myOrder = new Order(); myOrder.OrderDate = DateTime.Now; myOrder.RequiredDate = DateTime.Now.AddDays(1); myOrder.Freight = 34; Order_Detail myItem1 = new Order_Detail(); myItem1.Product = chai; myItem1.Quantity = 12345; Order_Detail myItem2 = new Order_Detail(); myItem2.Product = tofu; myItem2.Quantity = 3; myOrder.Order_Details.Add(myItem1); myOrder.Order_Details.Add(myItem2); Customer myCustomer = northwind.Customers.Single(c => c.CompanyName == "B's Beverages"); MyClass newOrder = new MyClass(); newOrder.OrderDate = DateTime.Now; newOrder.RequiredDate = DateTime.Now.AddDays(31); newOrder.Freight = 35; Order_Detail myItem3 = new Order_Detail(); myItem3.Product = tofu; myItem3.Quantity = 3; newOrder.Order_Details.Add(myItem3); myCustomer.Orders.Add(myOrder); myCustomer.Orders.Add(newOrder); As I said I'm able to add the newOrder object but unable to submit into the database.

    Read the article

  • Switching AM/PM in ASP.NET AJAX MaskedEdit localization

    - by Greg
    The sample page for the MaskedEdit says "Tip: Type 'A' or 'P' to switch AM/PM". Are these keys hardcoded? Does the control automatically change itself for cultures that use 12-hour designators that don't start with A or P? Or is just broken for those? example: Arabic (Saudi Arabia) - AM: ? Arabic (Saudi Arabia) - PM: ? Chinese (Taiwan) - AM: ?? Chinese (Taiwan) - PM: ?? Greek (Greece) - AM: pµ Greek (Greece) - PM: µµ Korean (Korea) - AM: ?? Korean (Korea) - PM: ?? Albanian (Albania) - AM: PD Albanian (Albania) - PM: MD Persian (Iran) - AM: ?.? Persian (Iran) - PM: ?.? Vietnamese (Vietnam) - AM: SA Vietnamese (Vietnam) - PM: CH Afrikaans (South Africa) - PM: nm Punjabi (India) - AM: ????? Punjabi (India) - PM: ??? Syriac (Syria) - AM: ?.? Syriac (Syria) - PM: ?.? If this control doesn't handle this situation, does anyone know of a control that does?

    Read the article

  • Examples of monoids/semigroups in programming

    - by jkff
    It is well-known that monoids are stunningly ubiquitous in programing. They are so ubiquitous and so useful that I, as a 'hobby project', am working on a system that is completely based on their properties (distributed data aggregation). To make the system useful I need useful monoids :) I already know of these: Numeric or matrix sum Numeric or matrix product Minimum or maximum under a total order with a top or bottom element (more generally, join or meet in a bounded lattice, or even more generally, product or coproduct in a category) Set union Map union where conflicting values are joined using a monoid Intersection of subsets of a finite set (or just set intersection if we speak about semigroups) Intersection of maps with a bounded key domain (same here) Merge of sorted sequences, perhaps with joining key-equal values in a different monoid/semigroup Bounded merge of sorted lists (same as above, but we take the top N of the result) Cartesian product of two monoids or semigroups List concatenation Endomorphism composition. Now, let us define a quasi-property of an operation as a property that holds up to an equivalence relation. For example, list concatenation is quasi-commutative if we consider lists of equal length or with identical contents up to permutation to be equivalent. Here are some quasi-monoids and quasi-commutative monoids and semigroups: Any (a+b = a or b, if we consider all elements of the carrier set to be equivalent) Any satisfying predicate (a+b = the one of a and b that is non-null and satisfies some predicate P, if none does then null; if we consider all elements satisfying P equivalent) Bounded mixture of random samples (xs+ys = a random sample of size N from the concatenation of xs and ys; if we consider any two samples with the same distribution as the whole dataset to be equivalent) Bounded mixture of weighted random samples Which others do exist?

    Read the article

  • Perl cron job stays running

    - by Dylan
    I'm currently using a cron job to have a Perl script that tells my Arduino to cycle my aquaponics system and all is well, except the Perl script doesn't die as intended. Here is my cron job: */15 * * * * /home/dburke/scripts/hal/bin/main.pl cycle And below is my Perl script: #!/usr/bin/perl -w # Sample Perl script to transmit number # to Arduino then listen for the Arduino # to echo it back use strict; use Device::SerialPort; use Switch; use Time::HiRes qw ( alarm ); $|++; # Set up the serial port # 19200, 81N on the USB ftdi driver my $device = '/dev/arduino0'; # Tomoc has to use a different tty for testing #$device = '/dev/ttyS0'; my $port = new Device::SerialPort ($device) or die('Unable to open connection to device');; $port->databits(8); $port->baudrate(19200); $port->parity("none"); $port->stopbits(1); my $lastChoice = ' '; my $pid = fork(); my $signalOut; my $args = shift(@ARGV); # Parent must wait for child to exit before exiting itself on CTRL+C $SIG{'INT'} = sub { waitpid($pid,0) if $pid != 0; exit(0); }; # What child process should do if($pid == 0) { # Poll to see if any data is coming in print "\nListening...\n\n"; while (1) { my $incmsg = $port->lookfor(9); # If we get data, then print it if ($incmsg) { print "\nFrom arduino: " . $incmsg . "\n\n"; } } } # What parent process should do else { if ($args eq "cycle") { my $stop = 0; sleep(1); $SIG{ALRM} = sub { print "Expecting plant bed to be full; please check.\n"; $signalOut = $port->write('2'); # Signal to set pin 3 low print "Sent cmd: 2\n"; $stop = 1; }; $signalOut = $port->write('1'); # Signal to arduino to set pin 3 High print "Sent cmd: 1\n"; print "Waiting for plant bed to fill...\n"; alarm (420); while ($stop == 0) { sleep(2); } die "Done."; } else { sleep(1); my $choice = ' '; print "Please pick an option you'd like to use:\n"; while(1) { print " [1] Cycle [2] Relay OFF [3] Relay ON [4] Config [$lastChoice]: "; chomp($choice = <STDIN>); switch ($choice) { case /1/ { $SIG{ALRM} = sub { print "Expecting plant bed to be full; please check.\n"; $signalOut = $port->write('2'); # Signal to set pin 3 low print "Sent cmd: 2\n"; }; $signalOut = $port->write('1'); # Signal to arduino to set pin 3 High print "Sent cmd: 1\n"; print "Waiting for plant bed to fill...\n"; alarm (420); $lastChoice = $choice; } case /2/ { $signalOut = $port->write('2'); # Signal to set pin 3 low print "Sent cmd: 2"; $lastChoice = $choice; } case /3/ { $signalOut = $port->write('1'); # Signal to arduino to set pin 3 High print "Sent cmd: 1"; $lastChoice = $choice; } case /4/ { print "There is no configuration available yet. Please stab the developer."; } else { print "Please select a valid option.\n\n"; } } } } } Why wouldn't it die from the statement die "Done.";? It runs fine from the command line and also interprets the 'cycle' argument fine. When it runs in cron it runs fine, however, the process never dies and while each process doesn't continue to cycle the system it does seem to be looping in some way due to the fact that it ups my system load very quickly. If you'd like more information, just ask. EDIT: I have changed to code to: #!/usr/bin/perl -w # Sample Perl script to transmit number # to Arduino then listen for the Arduino # to echo it back use strict; use Device::SerialPort; use Switch; use Time::HiRes qw ( alarm ); $|++; # Set up the serial port # 19200, 81N on the USB ftdi driver my $device = '/dev/arduino0'; # Tomoc has to use a different tty for testing #$device = '/dev/ttyS0'; my $port = new Device::SerialPort ($device) or die('Unable to open connection to device');; $port->databits(8); $port->baudrate(19200); $port->parity("none"); $port->stopbits(1); my $lastChoice = ' '; my $signalOut; my $args = shift(@ARGV); # Parent must wait for child to exit before exiting itself on CTRL+C if ($args eq "cycle") { open (LOG, '>>log.txt'); print LOG "Cycle started.\n"; my $stop = 0; sleep(2); $SIG{ALRM} = sub { print "Expecting plant bed to be full; please check.\n"; $signalOut = $port->write('2'); # Signal to set pin 3 low print "Sent cmd: 2\n"; $stop = 1; }; $signalOut = $port->write('1'); # Signal to arduino to set pin 3 High print "Sent cmd: 1\n"; print "Waiting for plant bed to fill...\n"; print LOG "Alarm is being set.\n"; alarm (420); print LOG "Alarm is set.\n"; while ($stop == 0) { print LOG "In while-sleep loop.\n"; sleep(2); } print LOG "The loop has been escaped.\n"; die "Done."; print LOG "No one should ever see this."; } else { my $pid = fork(); $SIG{'INT'} = sub { waitpid($pid,0) if $pid != 0; exit(0); }; # What child process should do if($pid == 0) { # Poll to see if any data is coming in print "\nListening...\n\n"; while (1) { my $incmsg = $port->lookfor(9); # If we get data, then print it if ($incmsg) { print "\nFrom arduino: " . $incmsg . "\n\n"; } } } # What parent process should do else { sleep(1); my $choice = ' '; print "Please pick an option you'd like to use:\n"; while(1) { print " [1] Cycle [2] Relay OFF [3] Relay ON [4] Config [$lastChoice]: "; chomp($choice = <STDIN>); switch ($choice) { case /1/ { $SIG{ALRM} = sub { print "Expecting plant bed to be full; please check.\n"; $signalOut = $port->write('2'); # Signal to set pin 3 low print "Sent cmd: 2\n"; }; $signalOut = $port->write('1'); # Signal to arduino to set pin 3 High print "Sent cmd: 1\n"; print "Waiting for plant bed to fill...\n"; alarm (420); $lastChoice = $choice; } case /2/ { $signalOut = $port->write('2'); # Signal to set pin 3 low print "Sent cmd: 2"; $lastChoice = $choice; } case /3/ { $signalOut = $port->write('1'); # Signal to arduino to set pin 3 High print "Sent cmd: 1"; $lastChoice = $choice; } case /4/ { print "There is no configuration available yet. Please stab the developer."; } else { print "Please select a valid option.\n\n"; } } } } }

    Read the article

  • jQuery UI datepicker will not display - full code included

    - by Bill Brasky
    I am having trouble displaying the jQuery datepicker as shown here: http://jqueryui.com/demos/datepicker/ I believe I downloaded all of the proper files, but to be certain, I started from scratch and ripped the demo site. Not all of it, but what I believed to be the important parts. The result is no datepicker to be shown and no javascript errors. Here is my full code sample: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <link rel="stylesheet" href="http://static.jquery.com/ui/css/base2.css" type="text/css" media="all" /> <link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.1/themes/base/jquery-ui.css" type="text/css" media="all" /> <link rel="stylesheet" href="http://static.jquery.com/ui/css/demo-docs-theme/ui.theme.css" type="text/css" media="all" /> <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.1/jquery.min.js"></script> <script type="text/javascript" charset="utf-8" src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.1/jquery-ui.min.js"></script> <script type="text/javascript" charset="utf-8"> jQuery(function(){ jQuery("#datepicker").datepicker(); }); </script> </head> <body> <input type="text" id="datepicker" class="hasDatepicker" /> </body> </html> Any help would be very much appreciated. Thanks!

    Read the article

  • faster way to change xml to array(grails to flex)

    - by Anthony Umpad
    I have a large xml passed from grails to flex. When flex receives the xml, it converts the xml into an associative array object. Given the large xml file, it takes too long to complete the loop, is there any way in flex to make conversion faster? Below is my sample code. <xml> <car> <model>Vios</model> <type>Sedan</type> <color>Blue</color> </car> <car> <model>Camry</model> <type>Luxury</type> <color>Black</color> </car> </xml> *converted to the flex associative array below.* [Vios].type = Sedan .color = Blue [Camry].type = Luxury .color = Black *Below is a code I used in flex to convert the xml to the associative array object* var tempXML=xml.children() var tempArray:Array= new Array() for(var i:int=0;i<tempXML.length();i++) { tempArray[tempXML[i].@model]= new Object(); tempArray[tempXML[i].@model].color = tempXML[i][email protected](); tempArray[tempXML[i].@model].type = tempXML[i][email protected](); }

    Read the article

  • Storing high precision latitude/longitude numbers in iOS Core Data

    - by Bryan
    I'm trying to store Latitude/Longitudes in core data. These end up being anywhere from 6-20 digit precision. And for whatever reason, i had them as floats in Core Data, its rounding them and not giving me the exact values back. I tried "decimal" type, with no luck either. Are NSStrings my only other option? EDIT NSManagedObject: @interface Event : NSManagedObject { } @property (nonatomic, retain) NSDecimalNumber * dec; @property (nonatomic, retain) NSDate * timeStamp; @property (nonatomic, retain) NSNumber * flo; @property (nonatomic, retain) NSNumber * doub; Here's the code for a sample number that I store into core data: NSNumber *n = [NSDecimalNumber decimalNumberWithString:@"-97.12345678901234567890123456789"]; Code to access it again: NSNumber *n = [managedObject valueForKey:@"dec"]; NSNumber *f = [managedObject valueForKey:@"flo"]; NSNumber *d = [managedObject valueForKey:@"doub"]; Printed values: Printing description of n: -97.1234567890124 Printing description of f: <CFNumber 0x603f250 [0xfef3e0]>{value = -97.12345678901235146441, type = kCFNumberFloat64Type} Printing description of d: <CFNumber 0x6040310 [0xfef3e0]>{value = -97.12345678901235146441, type = kCFNumberFloat64Type}

    Read the article

  • Generating JavaScript in C# and subsequent testing

    - by Codebrain
    We are currently developing an ASP.NET MVC application which makes heavy use of attribute-based metadata to drive the generation of JavaScript. Below is a sample of the type of methods we are writing: function string GetJavascript<T>(string javascriptPresentationFunctionName, string inputId, T model) { return @"function updateFormInputs(value){ $('#" + inputId + @"_SelectedItemState').val(value); $('#" + inputId + @"_Presentation').val(value); } function clearInputs(){ " + helper.ClearHiddenInputs<T>(model) + @" updateFormInputs(''); } function handleJson(json){ clearInputs(); " + helper.UpdateHiddenInputsWithJson<T>("json", model) + @" updateFormInputs(" + javascriptPresentationFunctionName + @"()); " + model.GetCallBackFunctionForJavascript("json") + @" }"; } This method generates some boilerplace and hands off to various other methods which return strings. The whole lot is then returned as a string and written to the output. The question(s) I have are: 1) Is there a nicer way to do this other than using large string blocks? We've considered using a StringBuilder or the Response Stream but it seems quite 'noisy'. Using string.format starts to become difficult to comprehend. 2) How would you go about unit testing this code? It seems a little amateur just doing a string comparison looking for particular output in the string. 3) What about actually testing the eventual JavaScript output? Thanks for your input!

    Read the article

< Previous Page | 227 228 229 230 231 232 233 234 235 236 237 238  | Next Page >