Search Results

Search found 4940 results on 198 pages for 'understanding'.

Page 99/198 | < Previous Page | 95 96 97 98 99 100 101 102 103 104 105 106  | Next Page >

  • Assignment in python for loop possible?

    - by flyingcrab
    I have a dictionary d (and a seperate sorted list of keys, keys). I wanted the loop to only process entries where the value is False - so i tried the following: for key in keys and not d[key]: #do foo I suppose my understanding of python sytax is not what i thought it was - because the assignment doesnt suppose to have happened above, and a i get an instanciation error. The below works of course, but I'd really like to be able to use something like the code above.. possible? for key in keys: if d[key]: continue #foo time! Thanks!

    Read the article

  • How to write the Visitor Pattern for Abstract Syntax Tree in Python?

    - by bodacydo
    My collegue suggested me to write a visitor pattern to navigate the AST. Can anyone tell me more how would I start writing it? As far as I understand, each Node in AST would have visit() method (?) that would somehow get called (from where?). That about concludes my understanding. To simplify everything, suppose I have nodes Root, Expression, Number, Op and the tree looks like this: Root | Op(+) / \ / \ Number(5) \ Op(*) / \ / \ / \ Number(2) Number(444) Can anyone think of how the visitor pattern would visit this tree to produce output: 5 + 2 * 444 Thanks, Boda Cydo.

    Read the article

  • TCP-Connection Establishment = How to measure time based on Ping RRT?

    - by Tom
    Hello Experts, I would be greatful for help, understanding how long it takes to establish a TCP connection when I have the Ping RoundTripTip: According to Wikipedia a TCP Connection will be established in three steps: 1.SYN-SENT (=>CLIENT TO SERVER) 2.SYN/ACK-RECEIVED (=>SERVER TO CLIENT) 3.ACK-SENT (=>CLIENT TO SERVER) My Questions: Is it correct, that the third transmission (ACK-SENT) will not yet carry any payload (my data) but is only used for the connection establishement.(This leads to the conclusion, that the fourth packt will be the first packt to hold any payload....) Is it correct to assume, that when my Ping RoundTripTime is 20 milliseconds, that in the example given above, the TCP Connection establishment would at least require 30 millisecons, before any data can be transmitted between the Client and Server? Thank you very much Tom

    Read the article

  • Windows 64-bit registry v.s. 32-bit registry

    - by George2
    Hello everyone, I heard on Windows x64 architecture, in order to support to run both x86 and x64 application, there is two separate/different sets of Windows registry -- one for x86 application to access and the other for x64 application to access? For example, if a COM registers CLSID in the x86 set of registry, then x64 application will never be able to access the COM component by CLSID, because x86/x64 have different sets of registry? So, my question is whether my understanding of the above sample is correct? I also want to get some more documents to learn this topic, about the two different sets of registry on x64 architecture. (I did some search, but not found any valuable information.) thanks in advance, George

    Read the article

  • Strange thing about .NET 4.0 filesystem enumeratation functionality

    - by codymanix
    I just read a page of "Whats new .NET Framework 4.0". I have trouble understanding the last paragraph: To remove open handles on enumerated directories or files Create a custom method (or function in Visual Basic) to contain your enumeration code. Apply the MethodImplAttribute attribute with the NoInlining option to the new method. For example: [MethodImplAttribute(MethodImplOptions.NoInlining)] Private void Enumerate() Include the following method calls, to run after your enumeration code: * The GC.Collect() method (no parameters). * The GC.WaitForPendingFinalizers() method. Why the attribute NoInlining? What harm would inlining do here? Why call the garbage collector manually, why not making the enumerator implement IDisposable in the first place? I suspect they use FindFirstFile()/FindNextFile() API calls for the imlementation, so FindClose() has to be called in any case if the enumeration is done.

    Read the article

  • Maven grails plugin issue

    - by Jack
    I'm trying to create the pom for an existing grails project via: mvn grails:create-pom -Dourcompany.com Now, we have our maven repository available in a local nexus repo: http://ourcompany.com/nexus But when i run the above, i get the below error Downloading: http://ourcompany.com/nexus/content/groups/public/ourcompany/com/hibernate-core/3.3.1.GA/hibernate-core-3.3.1.GA.jar [INFO] Unable to find resource 'ourcompany.com:hibernate-core:jar:3.3.1.GA' in repository central (http://repo1.maven.org/maven2) [INFO] ------------------------------------------------------------------------ [ERROR] BUILD ERROR But it is in there at simply: http://ourcompany.com/nexus/content/groups/public/hibernate-core/3.3.1.GA/hibernate-core-3.3.1.GA.jar Ie, w/o the "ourcompany.com" path. From my perspective, it should just try to pull down hibernate w/o inserting the groupId, but maybe i'm not understanding how i'm supposed to run this command?

    Read the article

  • Integrate Jasper in Rails 3

    - by AndreDurao
    I'm trying to integrate a rails 3 app with jasper following this wiki: http://wiki.rubyonrails.org/rails/pages/HowtoIntegrateJasperReports But it seems that a lot of information isn't updated so it's been very hard to make it work by myself. I've also read a topic at ruby-forum: http://www.ruby-forum.com/topic/139453 with some details explained but still couldn't make it work. My first problem is related with the render_to_string method: When the controller method runs I receive a "Template is missing" error: this is the method: def report @customers = Customer.all send_doc(render_to_string(:template => report_customers_path, :layout => false), '/pdfs', 'report.jasper', "customers", 'pdf') end Although this seems simple I'm not understanding why is this happening. Doesn't render_to_string with layout = false suposed to get me the string result of that action? I also tried :action instead of :template, but it does the same. If anybody with some expertise with this integration could help... Thanks in advance, André

    Read the article

  • Classes / instances in Ontology

    - by SODA
    Hi, I'm trying to comprehend ontology basics. Here's an example: car (class) 2009 VW CC (sub-class or instance?) My neighbor's 2009 VW CC (instance) My issue is understanding what is "2009 VW CC" (as a car model). If you're making product model a sub-class in the ontology - all of a sudden your ontology becomes bloated with thousands of subclasses of a "car". That's redundant. At the same time we can't say "2009 VW CC" is an instance, at least it's not material instance of a class. Does it make sense to distinguish between regular instances and material (distinct physical objects)? At the other hand, if both are instances (of different nature so to say), then how can instance inherit properties / relations of a non-class?

    Read the article

  • Python's FTPLib too slow ?

    - by PyNEwbie
    I have been playing around with Python's FTP library and am starting to think that it is too slow as compared to using a script file in DOS? I run sessions where I download thousands of data files (I think I have over 8 million right now). My observation is that the download process seems to take five to ten times as long in Python than it does as compared to using the ftp commands in the DOS shell. Since I don't want anyone to fix my code I have not included any. I am more interested in understanding if my observation is valid or if I need to tinker more with the arguments.

    Read the article

  • fourier transform to transpose key of a wav file

    - by tbischel
    I want to write an app to transpose the key a wav file plays in (for fun, I know there are apps that already do this)... my main understanding of how this might be accomplished is to 1) chop the audio file into very small blocks (say 1/10 a second) 2) run an FFT on each block 3) phase shift the frequency space up or down depending on what key I want 4) use an inverse FFT to return each block to the time domain 5) glue all the blocks together But now I'm wondering if the transformed blocks would no longer be continuous when I try to glue them back together. Are there ideas how I should do this to guarantee continuity, or am I just worrying about nothing?

    Read the article

  • TFS: How to dectet changed files when loading a solution?

    - by marco.ragogna
    I am new to TFS integration with Visual Studio 2010, and I have a problem I would like to solve. Practically, when I open a solution, how can I detect, looking only at the Solution Explorer which file has been changed since my last login? I am able to discover the changed files if I look at the Latest column of Source Control Explorer but it is not so intuitive. I attach you an image for better understanding. I would like to have a different icon, not the lock, for frmAbout.vb (in this case), associated to the item in Solution Explorer. Do you have any idea how can I achieve this behavior? Or some alternatives?

    Read the article

  • Lucene's nested query evaluation regarding negation

    - by ponzao
    Hi, I am adding Apache Lucene support to Querydsl (which offers type-safe queries for Java) and I am having problems understanding how Lucene evaluates queries especially regarding negation in nested queries. For instance the following two queries in my opinion are semantically the same, but only the first one returns results. +year:1990 -title:"Jurassic Park" +year:1990 +(-title:"Jurassic Park") The simplified object tree in the second example is shown below. query : Query clauses : ArrayList [0] : BooleanClause "MUST" occur : BooleanClause.Occur "year:1990" query : TermQuery [1] : BooleanClause "MUST" occur : BooleanClause.Occur query : BooleanQuery clauses : ArrayList [0] : BooleanClause "MUST_NOT" occur : BooleanClause.Occur "title:"Jurassic Park"" query : TermQuery Lucene's own QueryParser seems to evaluate "AND (NOT" into the same kind of object trees. Is this a bug in Lucene or have I misunderstood Lucene's query evaluation? I am happy to give more information if necessary.

    Read the article

  • Handler invocation speed: Objective-C vs virtual functions

    - by Kerido
    I heard that calling a handler (delegate, etc.) in Objective-C can be even faster than calling a virtual function in C++. Is it really correct? If so, how can that be? AFAIK, virtual functions are not that slow to call. At least, this is my understanding of what happens when a virtual function is called: Compute the index of the function pointer location in vtbl. Obtain the pointer to vtbl. Dereference the pointer and obtain the beginning of the array of function pointers. Offset (in pointer scale) the beginning of the array with the index value obtained on step 1. Issue a call instruction. Unfortunately, I don't know Objective-C so it's hard for me to compare performance. But at least, the mechanism of a virtual function call doesn't look that slow, right? How can something other than static function call be faster?

    Read the article

  • Sync Framework, Local Database Cache, and my DAL

    - by Refracted Paladin
    I am creating a WPF app that needs to allow users to work in a temporary disconnected state and I plan to use a Local Database Cache. My question's are about my data access layer. Do you typically create the whole DAL to point at the Cache or both and create a switching mechanism? Is Entity's a good way to go for my DAL against the Cache? I am used to L2S but my understanding is that I can't use that against SQLCE, correct? Thanks! PS: Any good resources out there for using Sync, Linq, and WPF? Tutorials, videos, etc?

    Read the article

  • Soft Shadows in Raytracing 3D to 2D

    - by Myx
    Hello: I wish to implement soft shadows produced by area lights in my raytracer. I'm having trouble generating the random samples. So I have a scene in which I have an area light (represented as a circle) whose world (x,y,z) coordinates of the center are given, the radius is given, the normal of the plane on which the circle lies is given, as well as the color and attenuation factors. The sampling scheme I wish to use is the following: generate samples on the quadrilateral that encompasses the circle and discard points outside the circle until the required number of samples within the circle have been found. I'm having trouble understanding how I can transform the 3D coordinates of the center of the circle to its 2D representation (I don't think I can assume that the projection of the circle is on the x-y axis and thus just get rid of the z-component). I think the plane normal information should be used but I'm not sure how. Any and all suggestions are appreciated.

    Read the article

  • For a primary key of an integral type, why is it important to avoid gaps ?

    - by Jacques René Mesrine
    I am generating a surrogate key for a table & due to my hi/lo algorithm, everytime you reboot/restart the machine, gaps may appear. T1: current hi = 10000000 (sequence being dished out .. 1 to 100) Assume that current sequence is 10000050 T2: restart system. T3: System gives out the next_hi as 10000100 (sequence being dished out now ranges from 101 to 200) T4: Next request for a key returns 100001001 From a primary key or indexing internals perspective, why is it important that there be no gaps in the sequences ? I'm asking this for a deeper understanding of mysql specifically. Thanks

    Read the article

  • URL BNF search part does not make sense

    - by Asaf Mesika
    Hi, While implementing a Java regular expression for URL based on the URL BNF published by W3C, I've failed to understand the search part. As quoted: httpaddress h t t p : / / hostport [ / path ] [ ? search ] search xalphas [ + search ] xalphas xalpha [ xalphas ] xalpha alpha | digit | safe | extra | escape alpha a | b | c | d | e | f | g | h | i | j | k | l | m | n | o | p | q | r | s | t | u | v | w | x | y | z | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | digit 0 |1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 safe $ | - | _ | @ | . | & | + | - extra ! | * | " | ' | ( | ) | , Search claims it is xalphas seperated by a plus sign. xalphas can contain plus signs by it self, as claimed by safe. Thus according to my understanding , it should be: search xalphas Where am I wrong here?

    Read the article

  • Language/tech specific books which improve vendor-neutral development skills

    - by dotnetdev
    If I ask what the following books have in common: "Accelerated C# 2010, C# in Depth, Pro C# 2008", the answer would be that they would help me to improve my understanding of C# and secondly, my general coding skills. What language-specific/tech-specific books (like those named above) would teach me a great deal about general programming techniques and good habits? I'm thinking Java books would be very good for me (I code in C# primarily), as both these languages are similar and so I am sure that specialist books on Java threading, performance tuning, etc, can be applied to C# (not all 100% content of a Java book). Thanks

    Read the article

  • Which programming languages have helped you to understand programming better?

    - by Xaisoft
    Which programming languages not only make you more proficient in the particular language your are learning, but also have a direct impact on the way you think and understand programming in general; therefore, making you a better programmer in other languages. Basically, which languages have the biggest impact on understanding the how and why of different programming concepts? What about Scheme? I have heard good things about that. I thought about taking the simplest of problems and implementing them in various languages. Has anyone done this?

    Read the article

  • Building webparts with Visual Studio 2010 Express

    - by MalphasWats
    Hi, I'm trying to get started with building my own webparts, planning to follow this MSDN article. I've downloaded Visual C# 2010 Express - I'm not quite at the point where I feel comfortable dropping 1000 big ones yet, and I installed Visual Web Developer 2010 Express via the WPInstaller. Following through the tutorial, aside from the fact that I don't get the option to create a "Web Control Library", a gap I filled with this article, I can't seem to find the sn.exe tool (or the "Visual Studio 2005 Command Prompt"!). I know it's not quite a direct programming related question, but I can't even get the thing going yet! Any help is appreciated. Thanks EDIT:- I think I may be jumping the gun quite considerably, I wrote a simple hello world example and tried to build it but it doesn't have any references to the Microsoft.SharePoint packages and they don't appear in my lists. Am I understanding some more research I've done (namely this) correctly, in that I have to actually have a full installation of actual SharePoint on the machine I'm developing on?

    Read the article

  • reinventing the wheels: Node.JS/Event-driven programming v.s. Functional Programming?

    - by ivanTheTerrible
    Now there's all the hype lately about Node.JS, an event driven framework using Javascript callbacks. To my limited understanding, its primary advantage seems to be that you don't have to wait step by step sequentially (for example, you can fetch the SQL results, while calling other functions too). So my question is: how is this different, or better than just functional languages, like CL, Haskell, Clojure etc? If not better, then why don't people just do functional languages then (instead of reinventing the wheel with Javascript)? Please note that I have none experience in either Node.JS nor functional programming. So some basic explanation can be helpful.

    Read the article

  • Redirecting http request to two different weblogic servers using the Weblogic proxy and Apache2

    - by Jhon
    Hello All, I've read previous posts like "Redirecting https requests to two different weblogic servers using the Weblogic proxy and Apache2". But I have a different situation and I don't think I'm understanding this to well. I have an Apache 2 server (server1) that will receive http request for my application. Then I have two more servers (server2 and server3) with Web Logic 9.2 runing on ports 7000 (server1) and 8000 (server2). I want the users to enter appname.domain.com and be redirected between the two web logic servers, always keeping appname.domain.com (this is hidding servername:port from URL). How can I manage to do that? Thanks in advanced! Jhon.

    Read the article

  • java generics covariance

    - by soocracy42
    I am having trouble understanding the following article: http://www.ibm.com/developerworks/java/library/j-jtp01255.html Under, Generics are not covariant the author states, Because ln is a List, adding a Float to it seems perfectly legal. But if ln were aliased with li, then it would break the type-safety promise implicit in the definition of li -- that it is a list of integers, which is why generic types cannot be covariant. I can't understand the part where it says "if ln were aliased with li". What does the author means by alias?(reference?). The code snippet above the quoted line seems to illustrate WHAT is illegal in java and not WHY. It would be very helpful to me if somebody could explain with an example. Thanks in advance.

    Read the article

  • Setting the a caret in an JEditor Pane causes an exception.

    - by Elliott
    I have a JeditorPane which has some text in HTML format. When I execute the following command int len = editorPane.getText().length(); The value for len is 7473. But then I try to do the following: editorPane.setCaretPosition(4995); And I get the following exception: java.lang.IllegalArgumentException: bad position: 4995 My understanding is that I should only get this exception if the position at which I'm trying to set the caret is less than 0 or greater than the text length. It is neither. How can this be. Thank you, Elliott

    Read the article

  • Unexpected behavior with AudioQueueServices callback while recording audio

    - by rcw3
    I'm recording a continuous stream of data using AudioQueueServices. It is my understanding that the callback will only be called when the buffer fills with data. In practice, the first callback has a full buffer, the 2nd callback is 3/4 full, the 3rd callback is full, the 4th is 3/4 full, and so on. These buffers are 8000 packets (recording 8khz audio) - so I should be getting back 1s of audio to the callback each time. I've confirmed that my audio queue buffer size is correct (and is somewhat confirmed by the behavior). What am I doing wrong? Should I be doing something in the AudioQueueNewInput with a different RunLoop? I tried but this didn't seem to make a difference... By the way, if I run in the debugger, each callback is full with 8000 samples - making me think this is a threading / timing thing.

    Read the article

< Previous Page | 95 96 97 98 99 100 101 102 103 104 105 106  | Next Page >