Search Results

Search found 15637 results on 626 pages for 'memory efficient'.

Page 398/626 | < Previous Page | 394 395 396 397 398 399 400 401 402 403 404 405  | Next Page >

  • 2 Select or 1 Join query ?

    - by xRobot
    I have 2 tables: book ( id, title, age ) ---- 100 milions of rows author ( id, book_id, name, born ) ---- 10 millions of rows Now, supposing I have a generic id of a book. I need to print this page: Title: mybook authors: Tom, Graham, Luis, Clarke, George So... what is the best way to do this ? 1) Simple join like this: Select book.title, author.name From book, author WHERE ( author.book_id = book.id ) AND ( book.id = 342 ) 2) For avoid the join, I could make 2 simple query: Select title FROM book WHERE id = 342 Select name FROM author WHERE book_id = 342 What is the most efficient way ?

    Read the article

  • Dealing with Windows line-endings in Python

    - by Adam Nelson
    I've got a 700MB XML file coming from a Windows provider. As one might expect, the line endings are '\r\n' (or ^M in vi). What is the most efficient way to deal with this situation aside from getting the supplier to send over '\n' :-) Use os.linesep Use rstrip() (requiring opening the file ... which seems crazy) Using Universal newline support is not standard on my Mac Snow Leopard - so isn't an option. I'm open to anything that requires Python 2.6+ but it needs to work on Snow Leopard and Ubuntu 9.10 with minimal external requirements. I don't mind a small performance penalty but I am looking for the standard best way to deal with this.

    Read the article

  • How do I create a point system in a Rails app that assigns points to users and non-authenticated-use

    - by codyvbrown
    I'm building a question and answer application on top of twitter and I'm hitting some snags because I'm inevitably dealing with two classes of users: authenticated and non-authenticated. The site enable users to give points to other users, who may or may not be authenticated, and I want to create a site-wide point system where the application stores and displays this information on their profile. I want to save this point data to the user because that would be faster and more efficient but non-authenticated users aren't in our system, we only have the twitter handle. So instead we display the points in our system like this: @points = point.all( :select => "tag, count(*) AS count", # Return tag and count :group => 'tag', # Group by the tag :order => "2 desc", :conditions => {:twitter_handle => params[:username]}) Is there a better way to do this? Is there a better way to associate data with non-authenticated users?

    Read the article

  • NASM: Count how many bits in a 32 Bit number are set to 1.

    - by citronas
    I have a 32 Bit number and want to count know how many bits are 1. I'm thinking of this pseudocode: mov eax, [number] while(eax != 0) { div eax, 2 if(edx == 1) { ecx++; } shr eax, 1 } Is there a more efficient way? I'm using NASM on a x86 processor. (I'm just beginning with assembler, so please do not tell me to use code from extern libraries, because I do not even know how to include them ;) ) (I just found http://stackoverflow.com/questions/109023/best-algorithm-to-count-the-number-of-set-bits-in-a-32-bit-integer which also contains my solution. There are other solutions posted, but unfortunatly I can't seem to figure out, how I would write them in assembler)

    Read the article

  • Please suggest me the best way to design my database.

    - by Raymond Ho
    I have a table named "Pages" and a table named "Categories". Each entry of the table "Pages" is linked to the table "Categories". The "Categories" table have 5 entries, they are: "Car", "Websites", "Technology", "Mobile Phones", and "Interest". So each time I put an entry to the "Pages" table, I need to map it to the "Categories" table so are arranged properly. Here's my table: Pages ______ id [PK] name url Categories ______ id [PK] Categoryname Pages2Categories ______ Pages.id Categories.id So my question is, is this the most efficient way to create this kind of relationships between tables? It seems very amateur

    Read the article

  • Pass Session data to a Class Library without using a bunch of constructors?

    - by sah302
    Hi all, I've got my application here where literally every object has a lastUpdatedBy property. The information I put into here is the person's username, which is retrieved from the session("username") variable. How can I pass this data to my DAL in the class library? At first I was just passing in the value into each method, but this is ridiculous I thought, there should be no reason to do that every time a method is called. Then I thought well if I just put it in a constructor for each of the DAL related classes, that will make it even easier. However, even still on any given page, I've got a plethora of New() declarations, for which every single line I need to pass in the session username casted as a string. Is there an even still more efficient way of doing this so that I could only declare this in one place, and everything will know what it is and I can pass it to classes in a class library?

    Read the article

  • Efficiently using position to control actions

    - by John Ashmore
    I want to use position (returned from a gridview for e.g.) or a similar numeric integer to do various things, e.g. create a sprite, or in any command that wants something other than a number, e.g. I want to use something like: sprites.add(createSprite(R.drawable.image(position)); , where createSprite creates a sprite using the image supplied, instead of: if (position == 1) {sprites.add(createSprite(R.drawable.image1);} if (position == 2) {sprites.add(createSprite(R.drawable.image2);} ...etc There is an easy solution for strings: Most efficient method to use position to open a .java but what about for situations like this one?

    Read the article

  • Fast, Vectorizable method of taking floating point number modulus of special primes?

    - by caffiend
    Is there a fast method for taking the modulus of a floating point number? With integers, there are tricks for Mersenne primes, so that its possible to calculate y = x MOD 2^31 without needing division. Can any similar tricks be applied for floating point numbers? Preferably, in a way that can be converted into vector/SIMD operations, or moved into GPGPU code. The primes I'm interested in would be 2^7 and 2^31, although if there are more efficient ones for floating point numbers, those would be welcome.

    Read the article

  • Logging NHibernate SQL queries

    - by GuestMVCAsync
    Is there a way to access the full SQL query, including the values, inside my code? I am able to log SQL queries using log4net: <logger name="NHibernate.SQL" additivity="false"> <level value="ALL"/> <appender-ref ref="NHibernateSQLFileLog"/> </logger> However, I would like to find a way to log SQL queries from the code also. This way I will log the specific SQL query that causes an exception in my try/catch statement. Right now I have to data-mine the SQLFileLog to find the query that caused the exception when an exception occurs and it is not efficient.

    Read the article

  • Secondary keys in a B-tree

    - by Phenom
    Let's say that there is a file that contains an unsorted list of student information, which includes a student ID number as well as other information. I want to make a program that retrieves student information based on student ID number. In order to make it efficient, I store the student IDs in a B-tree. So when I enter a student ID number, it searches the B-tree to see if its there or not. It also does one more thing. If it finds the student ID number, then it also returns where in the file that student's information is. This is the secondary key. The program uses this information to locate the rest of the student's information and prints it to screen. Can this be done? Is this how a b-tree works?

    Read the article

  • How does Photoshop (Or drawing programs) blit?

    - by user146780
    I'm getting ready to make a drawing application in Windows. I'm just wondering, do drawing programs have a memory bitmap which they lock, then set each pixel, then blit? I don't understand how Photoshop can move entire layers without lag or flicker without using hardware acceleration. Also in a program like Expression Design, I could have 200 shapes and move them around all at once with no lag. I'm really wondering how this can be done without GPU help. I don't think super efficient algorithms could justify that? Thanks

    Read the article

  • Prims vs Polys: what are the pros and cons of each?

    - by Richard Inglis
    I've noticed that most 3d gaming/rendering environments represent solids as a mesh of (usually triangular) 3d polygons. However some examples, such as Second Life, or PovRay use solids built from a set of 3d primitives (cube, sphere, cone, torus etc) on which various operations can be performed to create more complex shapes. So my question is: why choose one method over the other for representing 3d data? I can see there might be benefits for complex ray-tracing operations to be able to describe a surface as a single mathematical function (like PovRay does), but SL surely isn't attempting anything so ambitious with their rendering engine. Equally, I can imagine it might be more bandwidth-efficient to serve descriptions of generalised solids instead of arbitrary meshes, but is it really worth the downside that SL suffers from (ie modelling stuff is really hard, and usually the results are ugly) - was this just a bad decision made early in SL's development that they're now stuck with? Or is it an artefact of what's easiest to implement in OpenGL?

    Read the article

  • Vim: Replacing a line with another one yanked before

    - by duddle
    At least once per day i have the following situation: A: This line should also replace line X ... X: This is line should be replaced I believe that I don't perform that task efficiently. What I do: Go to line A: AG Yank line A: yy Go to line X: XG Paste line A: P Move to old line: j Delete old line: dd This has the additional disadvantage that line X is now in the default register, which is annoying if I find another line that should be replaced with A. Yanking to and pasting from an additional register ("ayy, "aP) makes this simple task even less efficient. My Questions: Did I miss a built-in Vim command to replace a line yanked before? If not, how can I bind my own command that leaves (or restores) the yanked line in the default register?

    Read the article

  • The best way to deploy one site for two companies in ColdFusion?

    - by Ofeargall
    My client has multiple companies; different names/logos etc, but all the content on the sites are identical with the exception of said names/logos. In a ColdFusion environment, what would be the best way for me to serve up identical content and swap out the logos/company names on the fly so I can keep everything in one spot? Is this a jQuery solution? regex? Or will ColdFusion enable me to deploy this in an efficient manner based on the url and session variables?

    Read the article

  • building a pairwise matrix in scipy/numpy in Python from dictionaries

    - by user248237
    I have a dictionary whose keys are strings and values are numpy arrays, e.g.: data = {'a': array([1,2,3]), 'b': array([4,5,6]), 'c': array([7,8,9])} I want to compute a statistic between all pairs of values in 'data' and build an n by x matrix that stores the result. Assume that I know the order of the keys, i.e. I have a list of "labels": labels = ['a', 'b', 'c'] What's the most efficient way to compute this matrix? I can compute the statistic for all pairs like this: result = [] for elt1, elt2 in itertools.product(labels, labels): result.append(compute_statistic(data[elt1], data[elt2])) But I want result to be a n by n matrix, corresponding to "labels" by "labels". How can I record the results as this matrix? thanks.

    Read the article

  • Workstation hardware at does your company buy developers?

    - by Bosh
    I'm curious to know what workstation hardware companies are devoting to you, as a developer -- and how much they're spending. I'd consider this thread a big success if I could shed some light on these questions: Do engineers at big companies use substantially different hardware than engineers at start-ups companies? Does a fresh developer recruit at Google get substantially different hardware from someone in the same position at Microsoft or Yahoo!? Do programmers in more senior positions have more powerful hardware on their desks? Does anyone think faster hardware makes more efficient engineers?

    Read the article

  • Result of Long Positive Integers & Search and element in array..

    - by AGeek
    Hi, I have two Questions for which I cannot find answers by googling, but I find these questions very important for preparation.. Kindly explain only the logic, I will be able to code. In Search of Efficient Logic..... in terms of Memory and Time. WAP to add two long positive integers. What Data structure / data type we can use to store the numbers and result. What is the best way to search an element from an array in shortest time. Size of the array could be large enough, and any elements could be stored in the array(i.e. no range). Thanks.

    Read the article

  • How to find the largest square in the number (Java)

    - by Ypsilon IV
    Hello everyone, I want to find the largest square in the number, but I am stuck at some point. I would really appreciate some suggestions. This is what I've done so far: I take the number on the input, factorize into prime numbers, and put the sequence of prime numbers to ArrayList. Numbers are sorted, in a sense, thus the numbers in the sequence are increasing. For example, 996 is 2 2 3 83 1000 is 2 2 2 5 5 5 100000 is 2 2 2 2 2 5 5 5 5 5 My idea now is to count number of occurrences of each elements in the sequence, so if the number of occurrences is divisible by two, then this is the square. In this way, I can get another sequence, where the right most element divisible by two is the largest square. What is the most efficient way to count occurrences in the ArrayList? Or is there any better way to find the largest square? Many thanks in advance!

    Read the article

  • Copy an array backwards? Array.Copy?

    - by daniel
    I have a List<T> that I want to be able to copy to an array backwards, meaning start from List.Count and copy maybe 5 items starting at the end of the list and working its way backwards. I could do this with a simple reverse for loop; however there is probably a faster/more efficient way of doing this so I thought I should ask. Can I use Array.Copy somehow? Originally I was using a Queue as that pops it off in the correct order I need, but I now need to pop off multiple items at once into an array and I thought a list would be faster.

    Read the article

  • Can I serialize a BitArray to XML?

    - by SimonNet
    Hello I have a business class which I need to serialize to xml. It has a BitArray property. I have decorated it with [XmlAttribute] but the serialization is failing with To be XML serializable, types which inherit from ICollection must have an implementation of Add(System.Boolean) at all levels of their inheritance hierarchy. System.Collections.BitArray does not implement Add(System.Boolean). I am not sure whether its possible to serialize to xml? If not what would be an efficient means of serializing the BitArray Thanks for looking

    Read the article

  • RegEx to Reject Unescaped Character

    - by JDV72
    I want to restrict usage of unescaped ampersands in a particular input field. I'm having trouble getting a RegEx to kill usage of "&" unless followed by "amp;"...or perhaps just restrict usage of "& " (note the space). I tried to adapt the answer in this thread, but to no avail. Thanks. (FWIW, here's a RegEx I made to ensure that a filename field didn't contain restrited chars. and ended in .mp3. It works fine, but does it look efficient?)

    Read the article

  • Java escape HTML - string replace slow?

    - by cpf
    Hi StackOverflow, I have a Java application that makes heavy use of a large file, to read, process and give through to SolrEmbeddedServer (http://lucene.apache.org/solr/). One of the functions does basic HTML escaping: private String htmlEscape(String input) { return input.replace("&", "&amp;").replace(">", "&gt;").replace("<", "&lt;") .replace("'", "&apos;").replaceAll("\"", "&quot;"); } While profiling the application, the program spends roughly 58% of the time in this function, a total of 47% in replace, and 11% in replaceAll. Now, is the Java replace that slow, or am I on the right path and should I consider the program efficient enough to have its bottleneck in Java and not in my code? (Or am I replacing wrong?) Thanks in advance!

    Read the article

  • Sql Server XML-type column duplicate entry detection

    - by aaaa bbbb
    In Sql Server I am using an XML type column to store a message. I do not want to store duplicate messages. I only will have a few messages per user. I am currently querying the table for these messages, converting the XML to string in my C# code. I then compare the strings with what I am about to insert. Unfortunately, Sql Server pretty-prints the data in the XML typed fields. What you store into the database is not necessarily exactly the same string as what you get back out later. It is functionally equivalent, but may have white space removed, etc. Is there an efficient way to compare an XML string that I am considering inserting with those that are already in the database? As an aside, if I detect a duplicate I need to delete the older message then insert the replacement.

    Read the article

  • Help with MySQL database structure - user notification system

    - by Simon
    Hi, I'd like to send global notifications to my users (1000+ users) and allow them to close the notification box once they have read the message. Basically I may send one notification per week globally ie/ each user get the same message and they are not personal in nature. What is the best way to achieve this? Create 2 tables: **tb_messages** message_id massage_title message_content **tb_read_messages** user_id message_id is-read That way i can just show each user the current notifications that are not read? select * from tb_read_messages WHERE user_id = $user_id AND is-read = no OR is there a more efficient way? Thanks!!!

    Read the article

  • Removing unused selectors in a CSS stylesheet?

    - by Legend
    I've been developing a web app for a few weeks now and ended up with about a 1000 lines. I am sure not all the selectors are being used and am trying to clean it up. At the same time, I don't want to do it manually for obvious reasons. Is there a safe and an efficient way to remove unused selectors? For this, am I supposed to navigate the entire website to let it know which selectors are not being used? (I use javascript to add some selectors so these might not show up until a particular usecase is seen)

    Read the article

< Previous Page | 394 395 396 397 398 399 400 401 402 403 404 405  | Next Page >