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  • What are the benefits of `while(condition) { //work }` and `do { //work } while(condition)`?

    - by Shaharyar
    I found myself confronted with an interview question where the goal was to write a sorting algorithm that sorts an array of unsorted int values: int[] unsortedArray = { 9, 6, 3, 1, 5, 8, 4, 2, 7, 0 }; Now I googled and found out that there are so many sorting algorithms out there! Finally I could motivate myself to dig into Bubble Sort because it seemed pretty simple to start with. I read the sample code and came to a solution looking like this: static int[] BubbleSort(ref int[] array) { long lastItemLocation = array.Length - 1; int temp; bool swapped; do { swapped = false; for (int itemLocationCounter = 0; itemLocationCounter < lastItemLocation; itemLocationCounter++) { if (array[itemLocationCounter] > array[itemLocationCounter + 1]) { temp = array[itemLocationCounter]; array[itemLocationCounter] = array[itemLocationCounter + 1]; array[itemLocationCounter + 1] = temp; swapped = true; } } } while (swapped); return array; } I clearly see that this is a situation where the do { //work } while(cond) statement is a great help to be and prevents the use of another helper variable. But is this the only case that this is more useful or do you know any other application where this condition has been used?

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  • Using LINQ to isolate a particular obect from a list of objects

    - by dezkev
    Hello All, I am trying my hand at making an invaders clone. there are 30 aliens arranged in a 5x 6 matrix on screen. I need to give the bottom most alien the ability to fire a shot. I am using LINQ to group the aliens into 5 groups based on Location.X and then sort the groups descending.I then need to choose one of the groups ( that gives me 5 groups) and select the First alien in the group and use it;s coordinate to fire a shot. My code below ,well ,works , but aliens in ANY row are merrily firing shots- not just the bottom most. Pl look at my code below and tell me whats wrong. (r = an instance of the Random class, all aliens are in a list called invaders). { var query = (from inv in invaders group inv by inv.Location.X into invgroup orderby invgroup.Key descending select invgroup).ToList(); var invfirst = query[r.Next(query.Count)].First(); invaderShots.Add(new Shot( new Point(invfirst.Area.X + invfirst.Area.Width / 2, invfirst.Area.Y + invfirst.Area.Height + 5), displayrect, Shot.Direction.Down)); }

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  • How to reduce a data frame keeping the order for other columns

    - by betabandido
    I am trying to reduce a data frame using the max function on a given column. I would like to preserve other columns but keeping the values from the same rows where each maximum value was selected. An example will make this explanation easier. Let us assume we have the following data frame: dframe <- data.frame(list(BENCH=sort(rep(letters[1:4], 4)), CFG=rep(1:4, 4), VALUE=runif(4 * 4) )) This gives me: BENCH CFG VALUE 1 a 1 0.98828096 2 a 2 0.19630597 3 a 3 0.83539540 4 a 4 0.90988296 5 b 1 0.01191147 6 b 2 0.35164194 7 b 3 0.55094787 8 b 4 0.20744004 9 c 1 0.49864470 10 c 2 0.77845408 11 c 3 0.25278871 12 c 4 0.23440847 13 d 1 0.29795494 14 d 2 0.91766057 15 d 3 0.68044728 16 d 4 0.18448748 Now, I want to reduce the data in order to select the maximum VALUE for each different BENCH: aggregate(VALUE ~ BENCH, dframe, FUN=max) This gives me the expected result: BENCH VALUE 1 a 0.9882810 2 b 0.5509479 3 c 0.7784541 4 d 0.9176606 Next, I tried to preserve other columns: aggregate(cbind(VALUE, CFG) ~ BENCH, dframe, FUN=max) This reduction returns: BENCH VALUE CFG 1 a 0.9882810 4 2 b 0.5509479 4 3 c 0.7784541 4 4 d 0.9176606 4 Both VALUE and CFG are reduced using max function. But this is not what I want. For instance, in this example I would like to obtain: BENCH VALUE CFG 1 a 0.9882810 1 2 b 0.5509479 3 3 c 0.7784541 2 4 d 0.9176606 2 where CFG is not reduced, but it just keeps the value associated to the maximum VALUE for each different BENCH. How could I change my reduction in order to obtain the last result shown?

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  • Loading specific files from arbitrary directories?

    - by Haydn V. Harach
    I want to load foo.txt. foo.txt might exist in the data/bar/ directory, or it might exist in the data/New Folder/ directory. There might be a different foo.txt in both of these directories, in which case I would want to either load one and ignore the other according to some order that I've sorted the directories by (perhaps manually, perhaps by date of creation), or else load them both and combine the results somehow. The latter (combining the results of both/all foo.txt files) is circumstantial and beyond the scope of this question, but something I want to be able to do in the future. I'm using SDL and boost::filesystem. I want to keep my list of dependencies as small as possible, and as cross-platform as possible. I'm guessing that my best bet would be to get a list of every directory (within the data/ folder), sort/filter this list, then when I go to load foo.txt, I search for it in each potential directory? This sounds like it would be very inefficient, if I have dozens of potential directories to search through every time. What's the best way to go about accomplishing this? Bonus: What if I want some of the directories to be archives? ie. considering both data/foo/ and data/bar.zip to both be valid, and pull foobar.txt from either one without caring.

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  • How to create a desktop shortcut to a website with website logo as icon?

    - by Wbdvlpr
    Hi I need a solution which allows users to create a desktop shortcut to a website, preferably with website logo as shortcut icon. There are ways users can create shortcut such as drag drop favicon or right click create new shortcut etc. This works but also creates the shortcut with default IE icon on windows. I am trying to avoid this method for this icon and some other reasons. I thought of creating a website-title.URL file, and tell users to download and save file to their desktop, again this works but doesn't solve the icon problem as the website logo (.ico) has to be at local disk and at a pre-specified location [IconFile=path]. I was wondering if it is possible to create a some sort of installer or windows application which users can download from the website. Once its executed by user, it creates this .URL file on user desktop which have IconFile path pre-specified, and copy the website-logo.ico at path specified in .URL file etc. So my questions are - Is it possible to create such a solution? What programming languages can be used to achieve this? Can this installer/app be made to work on non-windows machines as well? From developments point of view how big project it is? if I have to hire a programmer to do this. Please let me know if you need more information. Thanks

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  • Get parent attribute within new child form?

    - by dannymcc
    I have a simple Rails 3 application and I am trying to create a new record that belongs to it's owner. It's working by passing the id to a hidden field in the new form of the child record. This works well and once the new child form submitted it correctly gets associated in the child/parent relationship. What I am trying to do, is lookup values form the parent within the new child form. The problem is that the child relationship is not yet created. Is there anyway I can use a .where lookup in the view? Or, is there a better way of doing this? At the moment I am passing the animal_id though to the new Claim form and it's inserted into a hidden field labelled animal_id. What I am trying to do: <%= @animal.where(:animal_id => params[:animal_id]).id %> The above would ideally get the animal ID from the soon-to-be-associated animal. Is there any sort of before_filter or anything that could take the passed params from the URL and temporarily create the relationship just for the new form view and then permanently create the relationship once the form is submitted? I've tried adding the following to my Claims controller and then called @animal.AnimalName in the view but I get NoMethodError: before_filter :find_animal protected def find_animal if params[:animal_id] Animal.find(params[:animal_id]) end end The URL of the new claim is correctly showing the animal ID so I'm not sure why it's not finding it: http://localhost:3000/claims/new?animal_id=1 The model relations are as follows: animal has_many claims animal has_one exclusion claim has_one animal exception has_one animal

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  • Visual Studio internal project references not always working

    - by Chris
    I am using Visual Studio and a solution with 10 or so projects in (mostly VB, some C#) which have various dependencies set up. Usually when I compile the solution it works fine. Occasionally when I do it I get a build error saying that one of the projects referenced is the wrong version (I think always the same one, possibly may be two that can cause problems). In this case going to the solution explorer and right clicking on the mentioned project and saying "rebuild" followed by another full build makes it work fine. I assume there is something set up wrong somewhere but I didn't set up the solution myself initially and a quick look through doesn't show anything immediately wrong. It feels like there is some kind of race condition, that VS is internally setting the version number of the project it needs before that project has been rebuilt and thus gets it wrong or something like that but I'm sure VS should handle all this sort of thing properly. Can anybody please suggest places that I could check for whether this has been correctly set up... And I should finally note that since I don't have reliable repro of this I may not be able to respond to questions too quickly. For example the obvious one of "Could you give the exact error message" will have to wait since I didn't think to copy it this morning, it was only after I cleared it up with the above steps that I thought to post here. Similarly any solutions may take a while to confirm.

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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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  • Django templatetag "order of processing"

    - by Jason Persampieri
    I am trying to write a set of template tags that allow you to easily specify js and css files from within the template files themselves. Something along the lines of {% requires global.css %}, and later in the request, {% get_required_css %}. I have this mostly working, but there are a couple of issues. We'll start with the 'timing' issues. Each template tag is made up of two steps, call/init and render. Every call/init happens before any render procedure is called. In order to guarantee that all of the files are queued before the {% get_required_css %} is rendered, I need to build my list of required files in the call/init procedures themselves. So, I need to collect all of the files into one bundle per request. The context dict is obviously the place for this, but unfortunately, the call/init doesn't have access to the context variable. Is this making sense? Anyone see a way around this (without resorting to a hack-y global request object)? Another possibility to store these in a local dict but they would still need to be tied to the request somehow... possibly some sort of {% start_requires %} tag? But I have no clue how to make that work either.

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  • Attempted GCF app for Android

    - by Aaron
    I am new to Android and am trying to create a very basic app that calculates and displays the GCF of two numbers entered by the user. Here is a copy of my GCF.java: package com.example.GCF; import java.util.Arrays; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.EditText; import android.widget.TextView; public class GCF extends Activity { private TextView mAnswer; private EditText mA, mB; private Button ok; private String A, B; private int iA, iB; public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); mA = (EditText) findViewById(R.id.entry); mB = (EditText) findViewById(R.id.entry1); ok = (Button) findViewById(R.id.ok); mAnswer = (TextView) findViewById(R.id.answer1); ok.setOnClickListener(new OnClickListener() { public void onClick(View v) { A = mA.getText().toString(); B = mB.getText().toString(); } }); // the String to int conversion happens here iA = Integer.parseInt(A.trim()); iB = Integer.parseInt(B.trim()); while (iA != iB) { int[] nums={ iA, iB, Math.abs(iA-iB) }; Arrays.sort(nums); iA=nums[0]; iB=nums[1]; } updateDisplay(); } private void updateDisplay() { mAnswer.setText( new StringBuilder().append(iA)); } } Any Suggestions? Thank you!

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  • Sending Email to a specific address without requiring user to specify their mail server details

    - by sgmoore
    Can anyone recommend a simple and reliable method of sending email notifications and possibly log files attachments from a C# program without requiring the installer or the user to configure the program by specifying server details and email addresses etc. (Mainly because they won't know the details, but also because they could change) The program will normally be run as a service of a Windows Server, but can be run on a client. I tried connecting to our own mail server and sending a email to myself, but some ISP's are blocking Port 25 on all servers but their own, so that method isn't working reliably. Tried sending email through gmail but that was less successful as the port they used was blocked by firewalls. Ditto webservices connecting on weird ports. Trying to use the local smptservice but did not work either. It would be nice, but not essential if it was not dependant on my own Internet connection/Servers. (Don't mind them being delayed, but prefer them not to get lost). Are there any webservices on http/https that allow you to do this sort of thing? TIA

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  • Generating python wrapper for 3ed party c++ dll using swig with

    - by MuraliK
    I am new bee to swig. I have a third party c++ dll with the following functions export. I want to call these dll functions in python. So thought of using swig to generate the wrapper using swig. I am not sure what sort of wrapper i need to generate (do i need to generate .lib or .dll to use it in python?). In case i need to generate .dll how do i do that using visual studio 2010. There are some call back function like SetNotifyHandler(void (__stdcall * nf)(int wp, void *lp)) in the bellow list. How do define such function in interface file. can someone help me plese? enter code here #ifndef DLL_H #define DLL_H #ifdef DLL_BUILD #define DLLFUNC __declspec(dllexport) #else #define DLLFUNC __declspec(dllimport) #endif #pragma pack(push) #pragma pack(1) #pragma pack(pop) extern "C" { DLLFUNC int __stdcall StartServer(void); DLLFUNC int __stdcall GetConnectionInfo(int connIndex, Info *buf); DLLFUNC void __stdcall SetNotifyWindow(HWND nw); DLLFUNC void __stdcall SetNotifyHandler(void (__stdcall * nf)(int wp, void *lp)); DLLFUNC int __stdcall SendCommand(int connIndex, Command *cmd); };

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  • Synthetic click doesn't switch application's menu bar (Mac OS X)

    - by Rok
    Hi. I'm developing some sort of air mouse application for iPhone platform. This applications connects to one computer service which generates mouse events on Mac OS X. I'm generating this events with CGEventCreateMouseEvent() and CGEventPost(). But I've encountered one problem. Let's say you are using Safari and then you click on free desktop space. If you do this with regular mouse it will hide Safari's top menu bar and show Finder menu bar. But on these synthetic events it doesn't act like that. Do I have to post some other event or set some additional properties? Here is my code for mouse up, mouse down: - (void)mouseUp:(int)button { int type = (button == LEFT_BUTTON) ? kCGEventLeftMouseUp : kCGEventRightMouseUp; int mouseButton = (button == LEFT_BUTTON) ? kCGMouseButtonLeft : kCGMouseButtonRight; leftMouseDown = (button == LEFT_BUTTON) ? NO : leftMouseDown; rightMouseDown = (button == RIGHT_BUTTON) ? NO : rightMouseDown; CGEventSourceRef source = CGEventSourceCreate(kCGEventSourceStateHIDSystemState); CGEventRef event = CGEventCreateMouseEvent (source, type, CGSCurrentInputPointerPosition(), mouseButton); CGEventSetType(event, type); CGEventPost(kCGHIDEventTap, event); CFRelease(event); } - (void)mouseDown:(int)button { int type = (button == LEFT_BUTTON) ? kCGEventLeftMouseDown : kCGEventRightMouseDown; int mouseButton = (button == LEFT_BUTTON) ? kCGMouseButtonLeft : kCGMouseButtonRight; leftMouseDown = (button == LEFT_BUTTON) ? YES : leftMouseDown; rightMouseDown = (button == RIGHT_BUTTON) ? YES : rightMouseDown; CGEventSourceRef source = CGEventSourceCreate(kCGEventSourceStateHIDSystemState); CGEventRef event = CGEventCreateMouseEvent (source, type, CGSCurrentInputPointerPosition(), mouseButton); CGEventSetType(event, type); CGEventPost(kCGHIDEventTap, event); CFRelease(event); }

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  • making an SQL date column visible to a Drupal view

    - by Donal
    I'm trying to make a table visible to Views. One of the columns has type date (as opposed to a Unix timestamp). The example I initially tried to copy from is in modules/comment.views.inc in the Views module: // timestamp (when comment was posted) $data['comments']['timestamp'] = array( 'title' => t('Post date'), 'help' => t('Date and time of when the comment was posted.'), 'field' => array( 'handler' => 'views_handler_field_date', 'click sortable' => TRUE, ), 'sort' => array( 'handler' => 'views_handler_sort_date', ), 'filter' => array( 'handler' => 'views_handler_filter_date', ), ); This makes the dates, which are all in the past year or so, show up as "1 Jan 1970 00:33", so evidently a value of '2010-05-12', for example, is being interpreted as 2010 seconds past 1 Jan 1970 00:00. Can anyone point me to a correct way of exporting date columns? EDIT: I'm following up on some clues found at http://drupal.org/node/476774 .

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  • On counting pairs of words that differ by one letter

    - by Quintofron
    Let us consider n words, each of length k. Those words consist of letters over an alphabet (whose cardinality is n) with defined order. The task is to derive an O(nk) algorithm to count the number of pairs of words that differ by one position (no matter which one exactly, as long as it's only a single position). For instance, in the following set of words (n = 5, k = 4): abcd, abdd, adcb, adcd, aecd there are 5 such pairs: (abcd, abdd), (abcd, adcd), (abcd, aecd), (adcb, adcd), (adcd, aecd). So far I've managed to find an algorithm that solves a slightly easier problem: counting the number of pairs of words that differ by one GIVEN position (i-th). In order to do this I swap the letter at the ith position with the last letter within each word, perform a Radix sort (ignoring the last position in each word - formerly the ith position), linearly detect words whose letters at the first 1 to k-1 positions are the same, eventually count the number of occurrences of each letter at the last (originally ith) position within each set of duplicates and calculate the desired pairs (the last part is simple). However, the algorithm above doesn't seem to be applicable to the main problem (under the O(nk) constraint) - at least not without some modifications. Any idea how to solve this?

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  • Speed/expensive of SQLite query vs. List.contains() for "in-set" icon on list rows

    - by kpdvx
    An application I'm developing requires that the app main a local list of things, let's say books, in a local "library." Users can access their local library of books and search for books using a remote web service. The app will be aware of other users of the app through this web service, and users can browse other users' lists of books in their library. Each book is identified by a unique bookId (represented as an int). When viewing books returned through a search result or when viewing another user's book library, the individual list row cells need to visually represent if the book is in the user's local library or not. A user can have at most 5,000 books in the library, stored in SQLite on the device (and synchronized with the remote web service). My question is, to determine if the book shown in the list row is in the user's library, would it be better to directly ask SQLite (via SELECT COUNT(*)...) or to maintain, in-memory, a List or int[] array of some sort containing the unique bookIds. So, on each row display do I query SQLite or check if the List or int[] array contains the unique bookId? Because the user can have at most 5,000 books, each bookId occupies 4 bytes so at most this would use ~ 20kB. In thinking about this, and in typing this out, it seems obvious to me that it would be far better for performance if I maintained a list or int[] array of in-library bookIds vs. querying SQLite (the only caveat to maintaining an int[] array is that if books are added or removed I'll need to grow or shrink the array by hand, so with this option I'll most likely use an ArrayList or Vector, though I'm not sure of the additional memory overhead of using Integer objects as opposed to primitives). Opinions, thoughts, suggestions?

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  • Practicing inserting data into an array by using binary search, few problems

    - by HelpNeeder
    I'm trying to create a method which inserts and then sort elements in form of binary form. The problem I am experiencing that my code doesn't insert data correctly which means that output does not appear to be in order at all. The list is not organized, and data is added in order that is being inserted. Now, 2 questions, what am I doing wrong here? And how to fix this? public void insertBinarySearch(long value) // put element into array { int j = 0; int lower = 0; int upper = elems-1; int cur = 0; while (cur < elems) { curIn = (lower + upper ) / 2; if(a[cur] < value) { j = cur + 1; break; } else if(a[cur] > value) { j = cur; break; } else { if(a[cur] < value) lower = cur + 1; else upper = cur - 1; } } for(int k = elems; k > j; k--) a[k] = a[k-1]; a[j] = value; elems++; }

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  • What should a hobbyist do to develop good programming skills after basics?

    - by thyrgle
    So I'll say right here that I'm no professional coder. I'm a hobbyist. And pretty much like other people I feel like I'm doing it wrong. Like this question A feeling that I'm not a good programmer if have began to feel like that. Now I know basically that they say you shouldn't worry and that your good even if you continuously doubt yourself. But, they are talking to him. I'm not like him (in the sense I'm more of a newbie)... I've been coding as a hobbyist for 3 years (3 hobbyist years mind you!) unlike his 10-11 years that he states. Also, the only thing I've probably read in-depth is Teach Yourself C++ in 21 Days. And before I continue, just so your not confused about the various questions I've posted on (mostly) iPhone and OpenGL, I have poked and prodded at those two things for a few months each and finally sort of got a hang of both of them. But, from what I've noticed, is that I suck at making good code. For me its not even a debate of whether I'm doing it wrong or not: I can tell (from the various spaghetti code I create and other various discrepancies I, and others, can see and have noted in my code). What is a good way to get rid of these awful habits of mine and do it in a more correct, or if there is no "correct way" then I mean "typical", way?

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  • Is it possible to create a null function that will not produce warnings?

    - by bbazso
    I have a logger in a c++ application that uses defines as follows: #define FINEST(...) Logger::Log(FINEST, _FILE, __LINE, __func, __VA_ARGS_) However what I would like to do is to be able to switch off these logs since they have a serious performance impact on my system. And, it's not sufficient to simply have my Logger not write to the system log. I really need to get rid of the code produced by the logs. In order to do this, I changed the define to: #define FINEST(...) Which works, but this produces a whole bunch of warning in my code since variables are unused now. So what I would like to have is a sort of NULL FUNCTION that would not actually exist, but would not produce warnings for the unused variables. So, said another way, I would like it to compile with no warnings (i.e. the compiler thinks that the variables are used for a function) but the function does not actually exist in the application (i.e. produces no performance hit). Is this possible? Thanks!

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  • Remove duplication's from my DropDownList

    - by user2976270
    In my controller i am returning list of my object with specific property: public ActionResult Index() { List<MyObject> list = db.MyObjects.Where(x => x.family == "Web").ToList(); ViewBag.Files = new SelectList(list, "Id", "protocol"); return View(); } This is my object: public class MyObject { public int id { get; set; } public string fileName { get; set; } public string browser { get; set; } public string protocol { get; set; } public string family { get; set; } } Index.cshtml: @Html.DropDownList("File", new SelectList(ViewBag.Files, "Id", "protocol_site"), "Select webmail site", new { style = "vertical-align:middle;" }) And i try to made 2 changes with no succeed: Remove all the duplication protocol from my DropDownListfor exapmle if i have 10 objects : 9 is doc protocol and 1 pdf i wand to see in my DropDownList only 2 items: DOC and PDF and not all the 10 items. Sort this DropDownList in alphabet order

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  • The most efficient way to calculate an integral in a dataset range

    - by Annalisa
    I have an array of 10 rows by 20 columns. Each columns corresponds to a data set that cannot be fitted with any sort of continuous mathematical function (it's a series of numbers derived experimentally). I would like to calculate the integral of each column between row 4 and row 8, then store the obtained result in a new array (20 rows x 1 column). I have tried using different scipy.integrate modules (e.g. quad, trpz,...). The problem is that, from what I understand, scipy.integrate must be applied to functions, and I am not sure how to convert each column of my initial array into a function. As an alternative, I thought of calculating the average of each column between row 4 and row 8, then multiply this number by 4 (i.e. 8-4=4, the x-interval) and then store this into my final 20x1 array. The problem is...ehm...that I don't know how to calculate the average over a given range. The question I am asking are: Which method is more efficient/straightforward? Can integrals be calculated over a data set like the one that I have described? How do I calculate the average over a range of rows?

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  • Large Switch statements: Bad OOP?

    - by Mystere Man
    I've always been of the opinion that large switch statements are a symptom of bad OOP design. In the past, I've read articles that discuss this topic and they have provided altnerative OOP based approaches, typically based on polymorphism to instantiate the right object to handle the case. I'm now in a situation that has a monsterous switch statement based on a stream of data from a TCP socket in which the protocol consists of basically newline terminated command, followed by lines of data, followed by an end marker. The command can be one of 100 different commands, so I'd like to find a way to reduce this monster switch statement to something more manageable. I've done some googling to find the solutions I recall, but sadly, Google has become a wasteland of irrelevant results for many kinds of queries these days. Are there any patterns for this sort of problem? Any suggestions on possible implementations? One thought I had was to use a dictionary lookup, matching the command text to the object type to instantiate. This has the nice advantage of merely creating a new object and inserting a new command/type in the table for any new commands. However, this also has the problem of type explosion. I now need 100 new classes, plus I have to find a way to interface them cleanly to the data model. Is the "one true switch statement" really the way to go? I'd appreciate your thoughts, opinions, or comments.

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  • Manual Linq to SQL entity framework mapping

    - by kprobst
    I've been playing with the O/R designer in VS and I was wondering if someone could shed come light on this. I'm used to OR mappers that are largely manual (homegrown and e.g., NHibernate). I don't mind encoding the entity classes myself, since they don't change all that often to begin with, and I have this irrational fear of designers and auto generated code as it is. I have noticed that the generated entity classes contain a lot of boilerplate extensibility methods, e.g. On[Property]Changed() and so on where [Property] is a mapped member of the class. These are placed in the setters of the property accessors. I assume it's OK if I don't include these when I do my hand coding, correct? They would be nice if I needed some sort of interception pattern but that's certainly not the case. I guess I just need to know if any of those methods are required by the entity framework to keep track of changes to the mapping types in order for things to work when updating the database. Thanks!

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  • Cocoa Drag and Drop, reading back the data. [Newbie]

    - by kodai
    Ok, I have a NSOutlineView set up, and I want it to capture PDF's if a pdf is dragged into the NSOutlineView. My first question, I have the following code: [outlineView registerForDraggedTypes:[NSArray arrayWithObjects:NSStringPboardType, NSFilenamesPboardType, nil]]; In all the apple Docs and examples I've seen I've also seen something like MySupportedType being an object registered for dragging. What does this mean? Do I change the code to be: [outlineView registerForDraggedTypes:[NSArray arrayWithObjects:@"pdf", NSStringPboardType, NSFilenamesPboardType, nil]]; Currently I have it set up to recognize drag and drop, and I can even make it spit out the URL of the dragged file once the drag is accepted, however, this leads me to my second question. I want to keep a copy of those PDF's app side. I suppose, and correct me if I'm wrong, that the best way to do this is to grab the data off the clipboard, save it in some persistant store, and that's that. (as apposed to using some sort of copy command and literally copying the file to the app director.) That being said, I'm not sure how to do that. I've the code: - (BOOL)outlineView:(NSOutlineView *)ov acceptDrop:(id <NSDraggingInfo>)info item:(id)item childIndex:(NSInteger)childIndex { NSPasteboard *pboard = [info draggingPasteboard]; NSURL *fileURL; if ( [[pboard types] containsObject:NSURLPboardType] ) { fileURL = [NSURL URLFromPasteboard:pboard]; // Perform operation using the file’s URL } NSData *data = [pboard dataForType:@"NSPasteboardTypePDF"]; But this never actually gets any data. Like I said before, it does get the URL, just not the data. Does anyone have any advise on how to get this going? Thanks so much!

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  • How to animate button text? (loading type of animation) - jquery?

    - by AL
    I got something that I want to do and want to see what you guys think and how can it be implemented. I got a form in a page and the form will submit to itself to perform some process (run functions) in a class. Upon clicking the submit button, I want to animate the button text to “SUBMIT .” -> “SUBMIT ..” -> “SUBMIT …” -> “SUBMIT ….” -> “SUBMIT ….” and then back again. Sort of “animate” the button text. Once the whole process is done, the button text will goes back to be “SUBMIT” text again. Please note that I am not looking for image button solution, meaning that I do not want to implement gif animated button image. Anyone done this before or know how this can be done? I have google but seems nothing of this kind to be found. Thanks! AL

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