Search Results

Search found 9706 results on 389 pages for 'aggregate functions'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 176/389 | < Previous Page | 172 173 174 175 176 177 178 179 180 181 182 183  | Next Page >

  • Two radically different queries against 4 mil records execute in the same time - one uses brute force.

    - by IanC
    I'm using SQL Server 2008. I have a table with over 3 million records, which is related to another table with a million records. I have spent a few days experimenting with different ways of querying these tables. I have it down to two radically different queries, both of which take 6s to execute on my laptop. The first query uses a brute force method of evaluating possibly likely matches, and removes incorrect matches via aggregate summation calculations. The second gets all possibly likely matches, then removes incorrect matches via an EXCEPT query that uses two dedicated indexes to find the low and high mismatches. Logically, one would expect the brute force to be slow and the indexes one to be fast. Not so. And I have experimented heavily with indexes until I got the best speed. Further, the brute force query doesn't require as many indexes, which means that technically it would yield better overall system performance. Below are the two execution plans. If you can't see them, please let me know and I'll re-post then in landscape orientation / mail them to you. Brute-force query: Index-based exception query: My question is, based on the execution plans, which one look more efficient? I realize that thing may change as my data grows.

    Read the article

  • PostgreSQL function question

    - by maxxtack
    CREATE FUNCTION foo() RETURNS text LANGUAGE plperl AS $$ return 'foo'; $$; CREATE FUNCTION foobar() RETURNS text LANGUAGE plperl AS $$ return foo() . 'bar'; $$; I'm trying to compose results using multiple functions, but when i call foobar() i get an empty result.

    Read the article

  • What is the best way to scale images in Java?

    - by Peter Kelley
    I have a web application written in Java (Spring, Hibernate/JPA, Struts2) where users can upload images and store them in the file system. I would like to scale those images so that they are of a consistent size for display on the site. What libraries or built in functions will offer the best results? I will consider the following criteria in making my decision (in this order): Free/Open Source (essential) Easy to implement Quality of results Performance Size of executable

    Read the article

  • adding javascript events to freemind maps

    - by pri_dev
    I have created freemind maps using the tool, right now in the process of integrating the map with my web application. I have some questions on the usage of freemind maps 1) Instead of using the freemindbrowser.html and the jar file to integrate a map with a website/ web app, can we do an export to Javascript from the tool and then integrate that exported file (.html) with the web site? 2) I want to be able to add javascript functions on events like node click, how do I do that? Thanks in Advance

    Read the article

  • How do I use multiple where clauses in GHCi?

    - by T.R.
    I'm playing around with GHCi for the first time, and I'm having some trouble writing multi-line functions. My code is as follows: Prelude> :{ Prelude| let diffSquares lst = abs $ squareOfSums lst - sumOfSquares lst Prelude| where Prelude| squareOfSums lst = (fst (sumsAndSquares lst))^2 Prelude| sumOfSquares lst = snd (sumsAndSquares lst) Prelude| sumsAndSquares = foldl (\(sms,sqrs) x -> (sms+x,sqrs+x^2)) (0,0) Prelude| :} It gives the following error: <interactive>:1:142: parse error on input `=' Could someone kindly point me in the direction of what I'm missing?

    Read the article

  • Numpy: Creating a complex array from 2 real ones?

    - by Duncan Tait
    I swear this should be so easy... Why is it not? :( In fact, I want to combine 2 parts of the same array to make a complex array: Data[:,:,:,0] , Data[:,:,:,1] These don't work: x = np.complex(Data[:,:,:,0], Data[:,:,:,1]) x = complex(Data[:,:,:,0], Data[:,:,:,1]) Am I missing something? Does numpy not like performing array functions on complex numbers? Here's the error: TypeError: only length-1 arrays can be converted to Python scalars Cheers

    Read the article

  • Image Transformation on iPhone, how to?

    - by Horace Ho
    Since I cannot pre-render all the images in PNGs and real-time image transformation functions are required, namely: skew perspective (like the transform action found in Photoshop) Which API (CoreAnimation? OpenGL ES?) should I look into? Even better, is there any sample code around? Thanks!

    Read the article

  • mvc external javascript referencing problem

    - by user281180
    I recently asked this question but to my suprise, it worked fine for some time and now has stopped again! I have a javascript in my script and I have added the link in my view as follows: It has certain functions which I can access once I have the script in my view. But when running I can see that the fucntions are not called instead i`m getting the error message Object expected at line 104. Why am I having this error and how can I solve it?

    Read the article

  • How can I perform a reverse string search in Excel without using VBA?

    - by e.James
    I have an Excel spreadsheet containing a list of strings. Each string is made up of several words, but the number of words in each string is different. Using built in Excel functions (no VBA), is there a way to isolate the last word in each string? Examples: Are you classified as human? - human? Negative, I am a meat popsicle - popsicle Aziz! Light! - Light!

    Read the article

  • How to prompt a streamed file for downloading in Java / Tomcat

    - by Clem
    Hello, I'm creating a java web application runing on a Tomcat server. One of the functions fill in a StringBuffer variable with data. At the end, I would like to propose the user to download the generated content packaged in a text file. This without having to store the file on the server. I've been searching for a code snippet but couldn't find anything corresponding ... I hope I've been clear enough on my problem. Thanks in advance,

    Read the article

  • php date list for specified duration

    - by user301584
    hi is there any php classes or functions, which will gives us all the days from specific duration? for example, if i want a list of dates from 25/03/2010 (25th march 2010) to 15/05/2010 (15th May 2010), it will give me: 25/03/2010 26/03/2010 26/03/2010 .... .... .... 14/05/2010 15/05/2010 thanks a lot for any help!

    Read the article

  • Does the <script> tag position in HTML affects performance of the webpage?

    - by Rahul Joshi
    If the script tag is above or below the body in a HTML page, does it matter for the performance of a website? And what if used in between like this: <body> ..blah..blah.. <script language="JavaScript" src="JS_File_100_KiloBytes"> function f1() { .. some logic reqd. for manipulating contents in a webpage } </script> ... some text here too ... </body> Or is this better?: <script language="JavaScript" src="JS_File_100_KiloBytes"> function f1() { .. some logic reqd. for manipulating contents in a webpage } </script> <body> ..blah..blah.. ..call above functions on some events like onclick,onfocus,etc.. </body> Or this one?: <body> ..blah..blah.. ..call above functions on some events like onclick,onfocus,etc.. <script language="JavaScript" src="JS_File_100_KiloBytes"> function f1() { .. some logic reqd. for manipulating contents in a webpage } </script> </body> Need not tell everything is again in the <html> tag!! How does it affect performance of webpage while loading? Does it really? Which one is the best, either out of these 3 or some other which you know? And one more thing, I googled a bit on this, from which I went here: Best Practices for Speeding Up Your Web Site and it suggests put scripts at the bottom, but traditionally many people put it in <head> tag which is above the <body> tag. I know it's NOT a rule but many prefer it that way. If you don't believe it, just view source of this page! And tell me what's the better style for best performance.

    Read the article

  • approximating log10[x^k0 + k1]

    - by Yale Zhang
    Greetings. I'm trying to approximate the function Log10[x^k0 + k1], where .21 < k0 < 21, 0 < k1 < ~2000, and x is integer < 2^14. k0 & k1 are constant. For practical purposes, you can assume k0 = 2.12, k1 = 2660. The desired accuracy is 5*10^-4 relative error. This function is virtually identical to Log[x], except near 0, where it differs a lot. I already have came up with a SIMD implementation that is ~1.15x faster than a simple lookup table, but would like to improve it if possible, which I think is very hard due to lack of efficient instructions. My SIMD implementation uses 16bit fixed point arithmetic to evaluate a 3rd degree polynomial (I use least squares fit). The polynomial uses different coefficients for different input ranges. There are 8 ranges, and range i spans (64)2^i to (64)2^(i + 1). The rational behind this is the derivatives of Log[x] drop rapidly with x, meaning a polynomial will fit it more accurately since polynomials are an exact fit for functions that have a derivative of 0 beyond a certain order. SIMD table lookups are done very efficiently with a single _mm_shuffle_epi8(). I use SSE's float to int conversion to get the exponent and significand used for the fixed point approximation. I also software pipelined the loop to get ~1.25x speedup, so further code optimizations are probably unlikely. What I'm asking is if there's a more efficient approximation at a higher level? For example: Can this function be decomposed into functions with a limited domain like log2((2^x) * significand) = x + log2(significand) hence eliminating the need to deal with different ranges (table lookups). The main problem I think is adding the k1 term kills all those nice log properties that we know and love, making it not possible. Or is it? Iterative method? don't think so because the Newton method for log[x] is already a complicated expression Exploiting locality of neighboring pixels? - if the range of the 8 inputs fall in the same approximation range, then I can look up a single coefficient, instead of looking up separate coefficients for each element. Thus, I can use this as a fast common case, and use a slower, general code path when it isn't. But for my data, the range needs to be ~2000 before this property hold 70% of the time, which doesn't seem to make this method competitive. Please, give me some opinion, especially if you're an applied mathematician, even if you say it can't be done. Thanks.

    Read the article

  • Is SQL DATEDIFF(year, ..., ...) an Expensive Computation?

    - by rlb.usa
    I'm trying to optimize up some horrendously complicated SQL queries because it takes too long to finish. In my queries, I have dynamically created SQL statements with lots of the same functions, so I created a temporary table where each function is only called once instead of many, many times - this cut my execution time by 3/4. So my question is, can I expect to see much of a difference if say, 1,000 datediff computations are narrowed to 100?

    Read the article

  • How do you automatically remove the preview window after autocompletion in Vim?

    - by Ben Davini
    I'm using omnifunc=pythoncomplete. When autocompleting a word (e.g., os.), I get the list of eligible class members and functions, as expected, as well as a scratch buffer preview window with documentation about the selected member or function. This is great, but after selecting the function I want, the preview window remains. I can get rid of it with ":pc", but I'd like it just to automatically disappear after I've selected my function, a la Eclipse. I've played around with "completeopt" but to no avail.

    Read the article

  • Dreamweaver javascript code hints

    - by xdevel2000
    I'd to use DW cs 4 but before to buy I want to test javascript code hints. However that feature doesn't work at all. I have an external .js library and then into an html file I load it but when I type functions or object by name nothing happen. Any idea?

    Read the article

  • Appending javascript script to end of page

    - by uzay95
    I am looking for a way to insert javascript code block to end of ASP.NET page. Page.ClientScript.RegisterClientScriptBlock(typeof(Page), "videoyuGoster", sScript, true); is appending to body but js codes are always requesting some js files didn't load or some functions are below of the script. How can i append scripts that i generated dynamically to the bottom of body? Thanks for your help.

    Read the article

  • iPhone: Create a single UIView from multiple clicks

    - by Cuzog
    I'm making a partial overlay modal in my app with the code from “Semi-Modal (Transparent) Dialogs on the iPhone” at ramin.firoozye.com. In doing so, the button that calls the modal is still visible and clickable. I will hide this button when the modal spawns, but I want to be sure if the user clicks very quickly twice, a new modal doesn't come up for each click. What is the best way to check that the modal doesn't already exist when calling it from the button click? You can download the test project here. For those that don't have xcode, the relevant functions are below: I call forth the modal on button click with this: - (IBAction)displayModal:(id)sender { ModalViewController *modalController = [[ModalViewController alloc] initWithNibName:@"ModalViewController" bundle:nil]; modalController.view.frame = CGRectOffset(modalController.view.frame, 0, 230); [self showModal:modalController.view]; } Then use this function to animate the custom modal over the current view: - (void)showModal:(UIView*) modalView { UIWindow* mainWindow = (((TestAppDelegate*) [UIApplication sharedApplication].delegate).window); CGPoint middleCenter = modalView.center; CGSize offSize = [UIScreen mainScreen].bounds.size; CGPoint offScreenCenter = CGPointMake(offSize.width / 2.0, offSize.height * 1.5); modalView.center = offScreenCenter; // we start off-screen [mainWindow addSubview:modalView]; // Show it with a transition effect [UIView beginAnimations:nil context:nil]; [UIView setAnimationDuration:0.4]; // animation duration in seconds modalView.center = middleCenter; [UIView commitAnimations]; } Then I dismiss the modal on button click with this: - (IBAction)dismissModal:(id)sender { [self hideModal:self.view]; } And then use these functions to animate the modal offscreen and clean itself up: - (void)hideModal:(UIView*) modalView { CGSize offSize = [UIScreen mainScreen].bounds.size; CGPoint offScreenCenter = CGPointMake(offSize.width / 2.0, offSize.height * 1.5); [UIView beginAnimations:nil context:modalView]; [UIView setAnimationDuration:0.7]; [UIView setAnimationDelegate:self]; [UIView setAnimationDidStopSelector:@selector(hideModalEnded:finished:context:)]; modalView.center = offScreenCenter; [UIView commitAnimations]; } - (void)hideModalEnded:(NSString *)animationID finished:(NSNumber *)finished context:(void *)context { UIView* modalView = (UIView *)context; [modalView removeFromSuperview]; [self release]; } Any help is greatly appreciated!

    Read the article

  • How to handle duplicate values in d3.js

    - by Mario
    First I'm a d3.js noob :) How you can see from the title I've got a problem with duplicated data and aggregate the values is no option, because the name represent different bus stops. In this example maybe the stops are on the fron side and the back side of a building. And of course I like to show the names on the x-axis. If i created an example and the result is a bloody mess, see jsFiddel. x = index name = bus stop name n = value I've got a json e.g.: [{ "x": 0, "name": "Corniche St / Abu Dhabi Police GHQ", "n": 113 }, { "x": 1, "name": "Corniche St / Nation Towers", "n": 116 }, { "x": 2, "name": "Zayed 1st St / Al Khalidiya Public Garden", "n": 146 }, ... { "x": 49, "name": "Hamdan St / Tariq Bin Zeyad Mosque", "n": 55 }] The problem: It is possible that the name could appear more then once e.g. { "x": 1, "name": "Corniche St / Nation Towers", "n": 116 } and { "x": 4, "name": "Corniche St / Nation Towers", "n": 105 } I like to know is there a way to tell d3.js not to use distinct names and instead just show all names in sequence with their values. Any ideas or suggestions are very welcome :) If you need more information let me know. Thanks in advanced Mario

    Read the article

  • class vs structure c#

    - by Enriquev
    I'm doing course 3354 (Implementing System Types and Interfaces in the .NET Framework 2.0) and it is said that for simple classes, with members variables and functions, it is better to use a struct than a class because of overhead. I have never heard of such a thing, what is the validity of this claim?

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 172 173 174 175 176 177 178 179 180 181 182 183  | Next Page >