Search Results

Search found 2219 results on 89 pages for 'constant learner'.

Page 14/89 | < Previous Page | 10 11 12 13 14 15 16 17 18 19 20 21  | Next Page >

  • Is it possible for a parent to use a child's constant or static variables from inside a static metho

    - by ryeguy
    Below is an example of what I'm trying to do. The parent can't access any of the child's variables. It doesn't matter what technique I use (static or constants), I just need some kind of functionality like this. class ParentClass { public static function staticFunc() { //both of these will throw a (static|const) not defined error echo self::$myStatic; echo self::MY_CONSTANT; } } class ChildClass extends ParentClass { const MY_CONSTANT = 1; public static $myStatic = 2; } ChildClass::staticFunc();

    Read the article

  • The Benefits of Constants

    - by onaclov2000
    I understand one of the big deals about constants is that you don't have to go through and update code where that constant is used all over the place. Thats great, but let's say you don't explicitly declare it as a constant. What benefit(s) exist(s) to take a variable that HAPPENS to actually not be changed and make it a constant, will this save on processing, and/or size of code...etc? Basically I have a program that the compiler is saying that a particular variable is not changed and thus can be declared a constant, I just wanted to know what the benefit to adding the constant qualifier to it would be, if it makes no difference then making that change adds no value and thus no point wasting time (this same scenario occurs in more then one place) going back and "fixing" all these variables. Thank you, onaclov

    Read the article

  • Installing bitarray in Python 2.6 on Windows

    - by John Fouhy
    I would like to install bitarray in Windows running python 2.6. I have mingw32 installed, and I have C:\Python26\Lib\distutils\distutils.cfg set to: [build] compiler = mingw32 If I type, in a cmd.exe window: C:\Documents and Settings\john\My Documents\bitarray-0.3.5>python setup.py install I get: [normal python messages skipped] C:\MinGW\bin\gcc.exe -mno-cygwin -mdll -O -Wall -IC:\Python26\include -IC:\Python26\PC -c bitarray/_bitarray.c -o build\temp.win32-2.6\Release\bitarray\_bitarray.o bitarray/_bitarray.c:2197: error: initializer element is not constant bitarray/_bitarray.c:2197: error: (near initialization for `BitarrayIter_Type.tp_getattro') bitarray/_bitarray.c:2206: error: initializer element is not constant bitarray/_bitarray.c:2206: error: (near initialization for `BitarrayIter_Type.tp_iter') bitarray/_bitarray.c:2232: error: initializer element is not constant bitarray/_bitarray.c:2232: error: (near initialization for `Bitarraytype.tp_getattro') bitarray/_bitarray.c:2253: error: initializer element is not constant bitarray/_bitarray.c:2253: error: (near initialization for `Bitarraytype.tp_alloc') bitarray/_bitarray.c:2255: error: initializer element is not constant bitarray/_bitarray.c:2255: error: (near initialization for `Bitarraytype.tp_free') error: command 'gcc' failed with exit status 1 Can anyone help?

    Read the article

  • Calculate posterior distribution of unknown mis-classification with PRTools in MATLAB

    - by Samuel Lampa
    I'm using the PRTools MATLAB library to train some classifiers, generating test data and testing the classifiers. I have the following details: N: Total # of test examples k: # of mis-classification for each classifier and class I want to do: Calculate and plot Bayesian posterior distributions of the unknown probabilities of mis-classification (denoted q), that is, as probability density functions over q itself (so, P(q) will be plotted over q, from 0 to 1). I have that (math formulae, not matlab code!): P(q|k,N) = Posterior * Prior / Normalization constant = P(k|q,N) * P(q|N) / P(k|N) The prior is set to 1, so I only need to calculate the posterior and normalization constant. I know that the posterior can be expressed as (where B(N,k) is the binomial coefficient): P(k|q,N) = B(N,k) * q^k * (1-q)^(N-k) ... so the Normalization constant is simply an integral of the posterior above, from 0 to 1: P(k|N) = B(N,k) * integralFromZeroToOne( q^k * (1-q)^(N-k) ) (The Binomial coefficient ( B(N,k) ) can be omitted thoughappears in both the posterior and normalization constant, so it can be omitted.) Now, I've heard that the integral for the normalization constant should be able to be calculated as a series ... something like: k!(N-k)! / (N+1)! Is that correct? (I have some lecture notes from with this series, but can't figure out if it is for the normalization constant integral, or for the posterior distribution of mis-classification (q)) Also, hints are welcome as how to practically calculate this? (factorials are easily creating truncation errors right?) ... AND, how to practically calculate the final plot (the posterior distribution over q, from 0 to 1).

    Read the article

  • Beware of const members

    - by nmarun
    I happened to learn a new thing about const today and how one needs to be careful with its usage. Let’s say I have a third-party assembly ‘ConstVsReadonlyLib’ with a class named ConstSideEffect.cs: 1: public class ConstSideEffect 2: { 3: public static readonly int StartValue = 10; 4: public const int EndValue = 20; 5: } In my project, I reference the above assembly as follows: 1: static void Main(string[] args) 2: { 3: for (int i = ConstSideEffect.StartValue; i < ConstSideEffect.EndValue; i++) 4: { 5: Console.WriteLine(i); 6: } 7: Console.ReadLine(); 8: } You’ll see values 10 through 19 as expected. Now, let’s say I receive a new version of the ConstVsReadonlyLib. 1: public class ConstSideEffect 2: { 3: public static readonly int StartValue = 5; 4: public const int EndValue = 30; 5: } If I just drop this new assembly in the bin folder and run the application, without rebuilding my console application, my thinking was that the output would be from 5 to 29. Of course I was wrong… if not you’d not be reading this blog. The actual output is from 5 through 19. The reason is due to the behavior of const and readonly members. To begin with, const is the compile-time constant and readonly is a runtime constant. Next, when you compile the code, a compile-time constant member is replaced with the value of the constant in the code. But, the IL generated when you reference a read-only constant, references the readonly variable, not its value. So, the IL version of the Main method, after compilation actually looks something like: 1: static void Main(string[] args) 2: { 3: for (int i = ConstSideEffect.StartValue; i < 20; i++) 4: { 5: Console.WriteLine(i); 6: } 7: Console.ReadLine(); 8: } I’m no expert with this IL thingi, but when I look at the disassembled code of the exe file (using IL Disassembler), I see the following: I see our readonly member still being referenced by the variable name (ConstVsReadonlyLib.ConstSideEffect::StartValue) in line 0001. Then there’s the Console.WriteLine in line 000b and finally, see the value of 20 in line 0017. This, I’m pretty sure is our const member being replaced by its value which marks the upper bound of the ‘for’ loop. Now you know why the output was from 5 through 19. This definitely is a side-effect of having const members and one needs to be aware of it. While we’re here, I’d like to add a few other points about const and readonly members: const is slightly faster, but is less flexible readonly cannot be declared within a method scope const can be used only on primitive types (numbers and strings) Just wanted to share this before going to bed!

    Read the article

  • Enablement 2.0 Get Specialized!

    - by michaela.seika(at)oracle.com
      Check the new OPN Certified Specialist Exam Study Guides – your quick reference to the training options to guide partners pass OPN Specialist Exams! What are the advantages of the Exam Study Guides? Cover the Implementation Specialist Exams that count towards OPN Specialization program. Capture Exam Topics, Exam Objectives and Training Options. Define the Exam Objectives by learner or practitioner level of knowledge: Learner-level: questions require the candidate to recall information to derive the correct answer Practitioner-level: questions require the candidate to derive the correct answer from an application of their knowledge. Map by each Exam Topic the alternative training options that are available at Oracle. Where to find the Exam Study Guides? On Enablement 2.0 > Spotlight On each Knowledge Zone > Implement On each Specialist Implementation Guided Learning Path For More Information Oracle Certification Program Beta Exams OPN Certified Specialist Exams OPN Certified Specialist FAQ Contact Us Please direct any inquiries you may have to Oracle Partner Enablement team at [email protected].

    Read the article

  • Implication of variable context switching time

    - by Rob
    Hi, I know that constant switching time of the Linux scheduler was a big achievement. I was just asking myself the question what would be the implication of a non-constant switching time. The only obvious reason I can think of is real-time systems where we have to meet deadlines. There it is obviously no ideal if the switching time is "random". Are there any other good reasons that favour constant switching times? Many thanks, Rob

    Read the article

  • O(log n) algorithm for computing rank of union of two sorted lists?

    - by Eternal Learner
    Given two sorted lists, each containing n real numbers, is there a O(log?n) time algorithm to compute the element of rank i (where i coresponds to index in increasing order) in the union of the two lists, assuming the elements of the two lists are distinct? I can think of using a Merge procedure to merge the 2 lists and then find the A[i] element in constant time. But the Merge would take O(n) time. How do we solve it in O(log n) time?

    Read the article

  • O(log n) algorithm to find the element having rank i in union of pre-sorted lists

    - by Eternal Learner
    Given two sorted lists, each containing n real numbers, is there a O(log?n) time algorithm to compute the element of rank i (where i coresponds to index in increasing order) in the union of the two lists, assuming the elements of the two lists are distinct? I can think of using a Merge procedure to merge the 2 lists and then find the A[i] element in constant time. But the Merge would take O(n) time. How do we solve it in O(log n) time?

    Read the article

  • O(log n) algorithm for merging lists and computing rank?

    - by Eternal Learner
    Given two sorted lists, each containing n real numbers, is there a O(log?n) time algorithm to compute the element of rank i (where i coresponds to index in increasing order) in the union of the two lists, assuming the elements of the two lists are distinct? I can think of using a Merge procedure to merge the 2 lists and then find the A[i] element in constant time. But the Merge would take O(n) time. How do we solve it in O(log n) time?

    Read the article

  • Switching to a career in Machine Learning

    - by Naive Machine Learner
    My day job is plain old software development. I am also doing my Masters in CS (part time, course based). I took a course on AI and found machine learning quite fascinating but like most courses it only offered a basic intro. I intend to learn more about Machine Learning and if possible get a job in that field. When I look at job postings in this field it is clear that a Phd in Machine learning (or prior experience in the field with considerable expertise) is required for most of them. I'm looking for advice on self learning to gain experience that'll useful in industry. At least, enough experience to get my foot in. I will do the obvious ones like reading text books, papers etc. Perhaps any open source efforts that I can participate in or something I could do on my own? Apologies if I'm being vague here but I hope there are at least a few of you who done a similar switch and can advise. Thanks !

    Read the article

  • Custom map solution using openstreetmap

    - by LearneR
    I want to work in real estate portal and I need to filter the result and list the properties in map view using openstreetmap (Client requirement). They gave this reference site . I started on yesterday only but the documentation and all I am not able to understand (as a beginner). Can we implement like this using openstreetmap? Where should I start at first? Also I have seen some of the users recommended openlayers, leaflet, mapquest in help answers. Which one is best for my requirement openstreetmap or thirdparty api? Please guide me to complete this task. I don't know where I am and where I have to start?

    Read the article

  • Problem mounting USB Mobile Broadband dongle in Ubuntu 13.04

    - by Still A Learner
    I have been using Ubuntu 13.04 since last two months and I have problem mounting my USB dongle. I have Lenovo G-580 series laptop. It has 3 USB ports which are 3.0. When I attach dongle to one of the three USB ports the device gets mounted immediately but in the other two ports I have to reboot the OS while the dongle is attached to the laptop in order to mount it and connect to the internet. My dongle is of ZTE. I don't get what is going wrong.

    Read the article

  • How To Get Browser To Open From Same Folder?

    - by Bad Learner
    I don't know how to make the title any more clear. Let me give an example - When I want to add an image to an article on my blog, I click "Browse" button in the image uploader, and then upload the image to the blog. The problem is, when I want to upload another image to my blog, I want the browser to look into the same directory; but it's always takes me to the "Recently Used" directory. Is there a way to change this? I hope I have made myself clear enough. EDIT: I only use Chrome, so I am referring to it.

    Read the article

  • Is "Interface inheritance" always safe?

    - by Software Engeneering Learner
    I'm reading "Effective Java" by Josh Bloch and in there is Item 16 where he tells how to use inheritance in a correct way and by inheritance he means only class inheritance, not implementing interfaces or extend interfaces by other interfaces. I didn't find any mention of interface inheritance in the entire book. Does this mean that interface inheritance is always safe? Or there are guidlines for interface inheritance?

    Read the article

  • Why does Java allow to implement different interfaces, each containing a method with the same signature?

    - by Software Engeneering Learner
    I've recently found that I can have two interfaces containing method with the same signature as a method in the other interface. And then I can have an interface or class that implements both of that interfaces. So the descendant class/interface has implicitly implements two different methods as a one method. Why is this allowed in Java? I can see a numerous problems that arises from that. Even eclipse only can find out about implementations for only one interface method, but for the second one it doesn't show any implementations at all. Also I believe there would be problems with automatic refactoring, like when you would like to change the signature of the method in one of the interfaces and IDE won't be able to correctly change that signature in all implementations, as they implement two different interfaces and how will IDE know what interface method it implementation descends. Why don't just make a compiler error like 'interfaces method names clashes' or something like that?

    Read the article

  • How to install Chrome browser properly via command line?

    - by Bad Learner
    Setting up and managing an Ubuntu server all by myself, in coming months, is a part of my current plans. Hence, I am planning a swtich from Windows to Linux - - Ubuntu. I now need to get some grip on the command line, since I am all used to Windows' GUI. Anyway... the most obvious start is installing apps on my computer, and I thought I should learn to do it via CLI. And this is what I did: $ apt-cache search chrome browser the results showed that the proper term is "chrome-browser," so... $ sudo apt-get install chrome-browser And then "Y" for the Y/n question. But the installation threw errors. (I do not have my PC at hand, so can't mention what error exactly.) Does someone see anything wrong with the commands I issued? I am probably missing some command(s) in between, I think.

    Read the article

  • About insertion sort and especially why it's said that copy is much faster than swap?

    - by Software Engeneering Learner
    From Lafore's "Data Structures and Algorithms in Java": (about insertion sort (which uses copy + shift instead of swap (used in bubble and selection sort))) However, a copy isn’t as time-consuming as a swap, so for random data this algo- rithm runs twice as fast as the bubble sort and faster than the selectionsort. Also author doesn't mention how time consuming shift is. From my POV copy is the simplest pointer assignment operation. While swap is 3x pointer assignment operations. Which doesn't take much time. Also shift of N elemtns is Nx pointer assignment operations. Please correct me if I'm wrong. Please explain, why what author says is true? I don't understand.

    Read the article

  • Help me understand a part of Java Language Specification

    - by Software Engeneering Learner
    I'm reading part 17.2.1 of Java language specification: http://docs.oracle.com/javase/specs/jls/se7/html/jls-17.html#jls-17.2.1 I won't copy a text, it's too long, but I would like to know, why for third step of sequence they're saying that If thread t was removed from m's wait set in step 2 due to an interrupt Thread couldn't get to step 2 it wasn't removed from wait set, because it written for the step 1: Thread t does not execute any further instructions until it has been removed from m's wait set Thus thread can't be removed from wait set in step 2 whatever it's due to, because it was already removed. Please help me understand this.

    Read the article

  • solve a partition misalignment?

    - by learner
    I have a new Dell XPS laptop which had Windows 7 installed in it. It also had a default extra partition for "Dell Utility". I installed Ubuntu in it on an Extended Partition along with windows and specified the logical partitions myself (for /,/home and swap). Now when I open Disk Utility , it shows this "Partition misaligned by 512 bytes" error for the Dell Utility partition and "Partition misaligned by 1024 bytes" for the entire Extended partition where Ubuntu is installed. Deleting the extended partition and re-installing Ubuntu may solve the problem of misalignment in the extended partition. But how about the Dell Utility partition? If I re-install Windows 7 Dell Utility wouldn't be a part of the re-install. So that may not solve it either. How do I fix this? Note: The extended partition I made contains an NTFS logical partition for holding data accessible by both OSes(basically a personal data partition). EDIT: I deleted all my Ubuntu partitions and re-installed Ubuntu like before,this time making them partitions with GParted via LiveCD. Now the only problem is that there is a misalignment in the Dell Utility partition. The other misalignment got fixed. Now how do I get rid of that issue?

    Read the article

  • Given a string of letters from alphabet insert frequency of each character in the string.in O(n) time and O(1) space [on hold]

    - by learner
    Below is my attempt void str_freq(char *str, int len) { char c; int cnt=0; c=str[0]; int i,j=0; for(i=0;i<len;i++) { if(c==str[i]) { cnt++; } else { c = str[i]; // printf(" %d ",cnt); str[j] = str[i-1]; str[j+1] = (char)(((int)'0')+cnt); j++; cnt=0; } } str[j+1]='\0'; printf("%s",str); } int main() { char str[] = "aaabbccccdeffgggg"; int length=strlen(str); str_freq(str,length); } I am getting wrong answer abcdef1 instead of a3b2c4d1e1f2g4. Please let me know where I am going wrong.

    Read the article

  • System Settings -> Additional Drivers is empty. How then do I install proprietary drivers?

    - by learner
    I use Ubuntu 12.04. My graphics card is Geforce GT540M. I opened Synaptic Package manager and installed the following: nvidia-common nvidia-settings-update nvidia-common nvidia-current nvidia-current-updates The following were installed before(when unity launcher looked normal): jockey-common psensor nvidia-settings jockey-gtk xserver-xorg-video-nouveau My intention was to use the right Nvidia drivers. But apparently it didn't rightly install the drivers and now I have Unity 2D running!

    Read the article

  • How are you coping with Ubuntu's Unity app launcher? (It auto-hides, can't minimize apps)

    - by Bad Learner
    [Firstly, let me tell you that this cannot be subjective in anyway, as I think at least Ubuntu beginners will have these questions boggling in their mind; and yes, this is a question that has a definite answer - - so, I am completely within the rules.] Okay, coming to the point, I see that Ubuntu uses Unity since v10.xx (netbook edition?) and carried the same to v11.04 & v11.10. As someone who's stuck to Windows for all these years, it's somewhat difficult to cope with Ubuntu's Unity, for the following reasons: [1] The Unity app launcher (to the screen's left) auto-hides when a window is maximized. [2]- And once launched, apps cannot be minimized by clicking the app's icon in the launcher. I have to go to the top-left of the screen and click the "_" button. I do know I can fix these issues by installing some configuration tool. But the thing is, if that's how it's meant to work, Canonical/Ubuntu would have designed it that way. But they didn't. Why? w.r.t above points [1], [2]: [1] EDITED: So, does it mean, it's good to work without maximizing the windows? Because if I maximize the window, the app launcher hides. And I need to hover the mouse to the left of the screen, wait a bit (even if it's a sec or even less, I can still feel the lag), and then click on the next app icon in the launcher to switch to it. I do know, I can use Alt+TAB to switch, but I am not sure which window comes next. This, I feel, isn't productive. Also, this makes me feel, Ubuntu is designed for large screens (it's nice on my 1920x1080p screen), because I can have two windows side-by-side or something like that on a large screen. This is not possible on smaller screens. [2]- Being able to minimize an application's window by clicking on its icon in the launcher (just like it works on Windows & probably elsewhere) would have been great, rather than having to go to the top-left and clicking the _ (minimize) button which brings up the app launcher itself (from hiding) most of the time. It's too tiring to have these small issues in the UI. I really would like to know how you are coping with these issues the way they are?

    Read the article

  • Display turns off when watching videos (then video starts to lag), how to fix it?

    - by Bad Learner
    Okay, here's the thing - - On my Ubuntu 11.10 64-bit installation, I have the display set to turn off automatically after 3 minutes of inactivity. There are two problems now: the display turns off even when I am watching videos. But I don't want to keep fiddling my mouse or keyboard when I am watching a movie. Okay, like I said above, the display turns off, then I move the mouse a bit each time, and the display turns back on. But now, the video doesn't play properly, it lags. A lot actually. Are these issues common? Can these be fixed?

    Read the article

< Previous Page | 10 11 12 13 14 15 16 17 18 19 20 21  | Next Page >