Search Results

Search found 31293 results on 1252 pages for 'database agnostic'.

Page 159/1252 | < Previous Page | 155 156 157 158 159 160 161 162 163 164 165 166  | Next Page >

• Will this make the object thread-safe?

  - by sharptooth

  I have a native Visual C++ COM object and I need to make it completely thread-safe to be able to legally mark it as "free-threaded" in th system registry. Specifically I need to make sure that no more than one thread ever accesses any member variable of the object simultaneously. The catch is I'm almost sure that no sane consumer of my COM object will ever try to simultaneously use the object from more than one thread. So I want the solution as simple as possible as long as it meets the requirement above. Here's what I came up with. I add a mutex or critical section as a member variable of the object. Every COM-exposed method will acquire the mutex/section at the beginning and release before returning control. I understand that this solution doesn't provide fine-grained access and this might slow execution down, but since I suppose simultaneous access will not really occur I don't care of this. Will this solution suffice? Is there a simpler solution?

  Read the article

• What is a good measure of strength of a link and influence of a node?

  - by Legend

  In the context of social networks, what is a good measure of strength of a link between two nodes? I am currently thinking that the following should give me what I want: For two nodes A and B: Strength(A,B) = (neighbors(A) intersection neighbors(B))/neighbors(A) where neighbors(X) gives the total number of nodes directly connected to X and the intersection operation above gives the number of nodes that are connected to both A and B. Of course, Strength(A,B) != Strength(B,A). Now knowing this, is there a good way to determine the influence of a node? I was initially using the Degree Centrality of a node to determine its "influence" but I somehow think its not a good idea because just because a node has a lot of outgoing links does not mean anything. Those links should be powerful as well. In that case, maybe using an aggregate of the strengths of each node connected to this node is a good idea to estimate its influence? I'm a little confused. Does anyone have any suggestions?

  Read the article

• Reconstructing simple 3d enviroment(room) from photo

  - by Riz

  I have photo of a room with three walls and floor/ceiling or both. I am trying to reconstruct this room in 3d asking user for minimal input. Right now I use 8 points defined by user, angles of left and right wall(they can be quite different from 90) and one size "InLeftBottom-InRightBottom"(I need to have real size of this room for later use). I have no info about user's camera(I can read EXIF to get FOV and use constant height but this can be only used as additional info). Is this possible to ask user for less info? Maybe it's possible to get wall angles without user interaction? Or maybe I am completly wrong and should use different approach?

  Read the article

• what is the best algorithm to use for this problem

  - by slim

  Equilibrium index of a sequence is an index such that the sum of elements at lower indexes is equal to the sum of elements at higher indexes. For example, in a sequence A: A[0]=-7 A[1]=1 A[2]=5 A[3]=2 A[4]=-4 A[5]=3 A[6]=0 3 is an equilibrium index, because: A[0]+A[1]+A[2]=A[4]+A[5]+A[6] 6 is also an equilibrium index, because: A[0]+A[1]+A[2]+A[3]+A[4]+A[5]=0 (sum of zero elements is zero) 7 is not an equilibrium index, because it is not a valid index of sequence A. If you still have doubts, this is a precise definition: the integer k is an equilibrium index of a sequence if and only if and . Assume the sum of zero elements is equal zero. Write a function int equi(int[] A); that given a sequence, returns its equilibrium index (any) or -1 if no equilibrium indexes exist. Assume that the sequence may be very long.

  Read the article

• Logic to mirror byte value around 128

  - by Kazar

  Hey, I have a need to mirror a byte's value around the centre of 128. So, example outputs of this function include: In 0 Out 255 In 255 Out 0 In 128 Out 128 In 127 Out 1 In 30 Out 225 In 225 Out 30 I'm driving myself nuts with this, I'm sure I'll kick myself when I read the answers. Cheers

  Read the article

• Why is undefined behavior allowed (as opposed to not compiling/crashing)?

  - by Roman A. Taycher

  I understand the reasons for compiler/interpreter language extensions but why is behaviour that has no valid definition allowed to fail silently/do weird things rather then throwing a compiler error? Is it because of the extra difficulty(impossible or simply time consuming) for the compiler to catch them)?

  Read the article

• Should we avoid to use Object as the input parameter/ output value of a method?

  - by developer.cyrus

  Take Java syntax as an example, though the question itself is language independent. If the following snippet takes an object MyAbstractEmailTemplate as input argument in the method setTemplate, the class MyGateway will then become tightly-coupled with the object MyAbstractEmailTemplate, which lessens the re-usability of the class MyGateway. A compromise is to use dependency-injection to ease the instantiation of MyAbstractEmailTemplate. This might solve the coupling problem to some extent, but the interface is still rigid, hardly providing enough ?exibility to other developers/ applications. So if we only use primitive data type (or even plain XML in web service) as the input/ output of a method, it seems the coupling problem no longer exists. So what do you think? public class MyGateway { protected MyAbstractEmailTemplate template; publoc void setTemplate(MyAbstractEmailTemplate template) { this.template = template; } }

  Read the article

• Arguments against Create or Update

  - by Nix

  Recently someone stated that they thought all Creates should be CreateOrUpdates. Instinctively i thought bad, but now I am trying to find out if I have any grounds. Situation interface IService{ void Create(Object a); void Update(Object a); } or interface IService{ void CreateOrUpdate(Object a); } My first thought is if you implemented everything CreateOrUpdate then you have no control if someone accidentally sends you wrong data, or concurrency issues where someone changes a "primary" field right before you call update.... But if you remove those cases, are there any other cons?

  Read the article

• Language independent logic question

  - by Sam

  If one has three fields in a db that they are querying an object by.... One of these fields must always be an associations id. Concerning the other two fields "only one needs to be true" What interpretation do you take or make of "only one needs to be true"?

  Read the article

• Can you generate a todo.txt file from \todo commands with Doxygen ?

  - by anno

  /// \todo Loop must be rewritten ... /// \todo Delete this loop Can Doxygen generate a todo.txt file containing these comments ?

  Read the article

• Issuing multiple requests using HTTP/1.1 Pipelining

  - by Robert S. Barnes

  When using HTTP/1.1 Pipelining what does the standard say about issuing multiple requests without waiting for each request to complete? What do servers do in practice? I ask because I once tried writing a client which would issue a batch of GET requests for multiple files and remember getting errors. I wasn't sure if it was due to me incorrectly issuing the GET's or needing to wait for each individual request to finish before issuing the next GET.

  Read the article

• What's the best platform for a static-website?

  - by Earlz

  Hello, I am building a static-website (as in, to change a page, we change the HTML and there is no DB or anything). Well, it will have a number of pages and I don't want to copy and paste the HTML navigation and layout code around everywhere. So what would be the best platform to use in this situation so I can have all my layout and "common" HTML markup all in one place?

  Read the article

• O(N log N) Complexity - Similar to linear?

  - by gav

  Hey All, So I think I'm going to get buried for asking such a trivial but I'm a little confused about something. I have implemented quicksort in Java and C and I was doing some basic comparissons. The graph came out as two straight lines, with the C being 4ms faster than the Java counterpart over 100,000 random integers. The code for my tests can be found here; android-benchmarks I wasn't sure what an (n log n) line would look like but I didn't think it would be straight. I just wanted to check that this is the expected result and that I shouldn't try to find an error in my code. I stuck the formula into excel and for base 10 it seems to be a straight line with a kink at the start. Is this because the difference between log(n) and log(n+1) increases linearly? Thanks, Gav

  Read the article

• Details to log when starting an application

  - by Karl

  To help support and anyone who may use one of my applications I tend to log a few things during the application startup. Currently I log: Start Time App Name App Author App Version App Classpath Current working directory Java vendor Java version Max heap size Taking into consideration this application may be used / supported by a whole host of people can anyone think of any other vital details which we / others should log for good practice?

  Read the article

• Exceptions over remote methods

  - by Andrei Vajna II

  What are the best practices for exceptions over remote methods? I'm sure that you need to handle all exceptions at the level of a remote method implementation, because you need to log it on the server side. But what should you do afterwards? Should you wrap the exception in a RemoteException (java) and throw it to the client? This would mean that the client would have to import all exceptions that could be thrown. Would it be better to throw a new custom exception with fewer details? Because the client won't need to know all the details of what went wrong. What should you log on the client? I've even heard of using return codes(for efficiency maybe?) to tell the caller about what happened. The important thing to keep in mind, is that the client must be informed of what went wrong. A generic answer of "Something failed" or no notification at all is unacceptable. And what about runtime (unchecked) exceptions?

  Read the article

• What programming languages do you consider indispensable in your experience?

  - by Federico Ramponi

  Each programming language comes with its concepts, best practices, libraries, tools, community, in one word: culture. Learning more than one programming language will make you a better programmer, for the more concepts you learn, the faster you will feel comfortable when the next language or technology will come. Mine, so far, are C, some C++, and Python, and many times I read that it would be worth learning LISP, for "the profound enlightenment experience you will have when you finally get it" (quoting Eric Raymond). My questions are: Which is the next one you would consider a good investment to learn? Of the many programming languages you have learnt and worked with, which ones do you consider to be an essential part of one's CS culture, and why? EDIT. Further question: is there any language you would sincerely advise to avoid as a waste of time? (The famous, and questionable, slatings in this letter from Dijkstra come to my mind.)

  Read the article

• Pi/Infinite Numbers

  - by Ben Shelock

  I'm curious about infinite numbers in computing, in particular pi. For a computer to render a circle it would have to understand pi. But how can it if it is infinite? Am I looking too much into this? Would it just use a rounded value?

  Read the article

• Design question: Should the client both create the session and the socket?

  - by the_drow

  I have three classes: Client Session Socket Both Session & Socket depeand on the Client to create both objects. A Session depeands on a Socket and no sockets are created without a session. Should the Client have a function that creates a Session pubically and a Socket privately? Doesn't it violate the law of demeter?

  Read the article

• When may I ask a question to fellow developers? (Rules before asking questions).

  - by Zwei Steinen

  I assigned a quite simple task to one junior developer today, and he kept pinging me EVERY 5 minutes for HOURS, asking STEP BY STEP, what to do. Whenever something went wrong, he simply copy&pasted the log and basically wrote, "An exception occurred. What should I do?" So I finally had to tell him, "If you want to be a developer, please start thinking a little bit. Read the error message. That's what they are for!". I also however, tell junior developers to ask questions before spending too much time trying to solve it themselves. This might sound contradictory, but I feel there is some kind of an implicit rule that distinguishes questions that should be asked fairly quickly and that should not (and I try to follow those rules when I ask questions..) So my question is, do you have any rules that you follow, or expect others to follow on asking questions? If so, what are they? Let me start with my own. If you have struggled for more than 90 min, you may ask that question (exceptions exists). If you haven't struggled for more than 15 min, you may not ask that question (if you are sure that the answer can not be found within 15 min, this rule does not have to apply). If it is completely out of your domain and you do not plan to learn that domain, you may ask that question after 15 min (e.g. if I am a java programmer and need to back up the DB, I may ask the DBA what procedure to follow after googling for 15 min). If it is a "local" question, whose answer is difficult to derive or for which resources is difficult to get (e.g. asking an colleague "what method xxx does" etc.), you may ask that question after 15 min. If the answer for it is difficult to derive, and you know that the other person knows the answer, you may ask the question after 15 min (e.g. asking a hibernate expert "What do I need to change else to make this work?". If the process to derive the answer is interesting and is a good learning opportunity, you may ask for hints but you may not ask for answers! What are your rules?

  Read the article

• when to make a method static

  - by Don

  Hi, I'd like to know how people decide whether to define a method as static. I'm aware that a method can only be defined as static if it doesn't require access to instance fields. So lets say we have a method that does not access instance fields, do you always define such a method as static, or only if you need to call it statically (without a reference to an instance). Perhaps another way of asking the same question, is whether you use static or non-static as the default? Thanks, Don

  Read the article

• Where do you get your application sounds from?

  - by Roberto Bonini

  Specifically for prompts, message boxes etc. Thanks

  Read the article

• 'goto' usage

  - by Landon

  I've long been under the impression that 'goto' should never be used if possible. While perusing libavcodec (which is written in C) the other day, I noticed multiple uses of it. Is it ever advantageous to use 'goto' in a language that supports loops and functions? If so, why?

  Read the article

• Best way to format if statement with multiple conditions.

  - by Matt690

  If you want to some code to execute based on two or more conditions which is the best way to format that if statement ? first example:- if(ConditionOne && ConditionTwo && ConditionThree) { Code to execute } Second example:- if(ConditionOne) { if(ConditionTwo ) { if(ConditionThree) { Code to execute } } } which is easiest to understand and read bearing in mind that each condition may be a long function name or something.

  Read the article

• Capturing system command output as a string

  - by dreeves

  Perl and PHP do this with backticks. For example: $output = `ls`; This code returns a directory listing into the variable $output. A similar function, system("ls"), returns the operating system return code for the given command. I'm talking about a variant that returns whatever the command prints to stdout. (There are better ways to get the list of files in a directory; the example code is an example of this concept.) How do other languages do this? Is there a canonical name for this function? (I'm going with "backtick"; though maybe I could coin "syslurp".)

  Read the article

• How do software events work internally?

  - by Duddle

  Hello! I am a student of Computer Science and have learned many of the basic concepts of what is going on "under the hood" while a computer program is running. But recently I realized that I do not understand how software events work efficiently. In hardware, this is easy: instead of the processor "busy waiting" to see if something happened, the component sends an interrupt request. But how does this work in, for example, a mouse-over event? My guess is as follows: if the mouse sends a signal ("moved"), the operating system calculates its new position p, then checks what program is being drawn on the screen, tells that program position p, then the program itself checks what object is at p, checks if any event handlers are associated with said object and finally fires them. That sounds terribly inefficient to me, since a tiny mouse movement equates to a lot of cpu context switches (which I learned are relatively expensive). And then there are dozens of background applications that may want to do stuff of their own as well. Where is my intuition failing me? I realize that even "slow" 500MHz processors do 500 million operations per second, but still it seems too much work for such a simple event. Thanks in advance!

  Read the article

< Previous Page | 155 156 157 158 159 160 161 162 163 164 165 166  | Next Page >