Search Results

Search found 80052 results on 3203 pages for 'data load performance'.

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 444/3203 | < Previous Page | 440 441 442 443 444 445 446 447 448 449 450 451  | Next Page >

  • require_once at the beginning or when really needed?

    - by takeshin
    Where should I put require_once statements, and why? Always on the beginning of a file, before the class, In the actual method when the file is really needed It depends ? Most frameworks put includes at the beginning and do not care if the file is really needed. Using autoloader is the other case here.

    Read the article

  • How to optimize this simple function which translates input bits into words?

    - by psihodelia
    I have written a function which reads an input buffer of bytes and produces an output buffer of words where every word can be either 0x0081 for each ON bit of the input buffer or 0x007F for each OFF bit. The length of the input buffer is given. Both arrays have enough physical place. I also have about 2Kbyte free RAM which I can use for lookup tables or so. Now, I found that this function is my bottleneck in a real time application. It will be called very frequently. Can you please suggest a way how to optimize this function? I see one possibility could be to use only one buffer and do in-place substitution. void inline BitsToWords(int8 *pc_BufIn, int16 *pw_BufOut, int32 BufInLen) { int32 i,j,z=0; for(i=0; i<BufInLen; i++) { for(j=0; j<8; j++, z++) { pw_BufOut[z] = ( ((pc_BufIn[i] >> (7-j))&0x01) == 1? 0x0081: 0x007f ); } } } Please do not offer any compiler specific or CPU/Hardware specific optimization, because it is a multi-platform project.

    Read the article

  • how do you convert data frame to a custom json format

    - by user1471980
    I need to convert a data frame to json fomrat in R. My data frame y is this: dput(y) structure(list(Name = structure(c(38L, 23L, 16L, 35L, 21L, 6L, 34L, 15L, 46L, 1L, 43L, 28L, 39L, 27L, 7L, 20L, 14L, 44L, 48L, 36L), .Label = c("server09", "server10", "server11", "server12", "server13", "server14", "server15", "server16", "server17", "server18", "server19", "server20", "server21", "server22", "server23", "server24", "server25", "server26", "server27", "server28", "server29", "server30", "server31", "server32", "server33", "server34", "server35", "server36", "server37", "server38", "server39", "server40", "server41", "server42", "server43", "server44", "server45", "server46", "server47", "server48", "server49", "server50", "server51", "server52", "server53", "server54", "server55", "server56", "server57", "server58"), class = "factor"), Date = c(1372737600, 1372737602, 1372737609, 1372737617, 1372737618, 1372737618, 1372737643, 1372737646, 1372737648, 1372737652, 1372737654, 1372737660, 1372737665, 1372737671, 1372737699, 1372737701, 1372737718, 1372737721, 1372737728, 1372737731), Cpu = c(3.9025, 36.3042, 2.6075, 3.1338, 0.9474, 0.149, 5.4401, 2.5652, 0.3612, 3.2651, 1.8703, 13.8967, 4.2438, 5.4401, 2.468, 0.9147, 1.4637, 7.2528, 6.119, 7.7009)), .Names = c("Name", "Date", "Cpu"), row.names = c(1L, 42L, 83L, 84L, 125L, 126L, 127L, 168L, 169L, 202L, 203L, 236L, 277L, 318L, 359L, 360L, 361L, 362L, 395L, 396L), class = "data.frame") I need my json file to look like this: [{ "name":'server13', "data": [ [1372737600,3.9025], [1372737602,10], [1372737609,10] ... [1372737731,20] ] }, { "name":'server14', "data": [ [1372737600,4], [1372737602,10], [1372737609,10] ... [1372737731,30] ] }] I used rjson package as the following: p <- toJSON(as.list(y)) I get this output: "{\"Name\":[\"server13\",\"servar14\",...],\"Date\":[1372737600,1372737602,..],\"Cpu\":[3.9025,36.3042,..]}" Is there an easy way to do this in R?

    Read the article

  • Need help with transferring data between MySQL db's using PHP

    - by JM4
    In one of the sites I manage, the client has decided to take on ACH/Bank Account administration where it was previously outsourced. As a result, the information submitted in our online form which used to simply store in a single database for processing now must sit in 'limbo' until the funds used for payment have been verified. My original plan is as follows: At the end of an enrollment, all form data is collected and stored in a single MySQL database. Our internal administrator will receive an email notification reminding him enrollments have taken place. He will process the ACH information collected and wait the 3-4 business days needed for payment to clear. Once the payment information has been returned as Good (haven't considered what I will do with the 'bad' yet), the administrator can log into a secure portal which allows him to click a button to 'process' the full information once compared and verified. the process is simplified as: Enrollment complete: data stored in DB 'A' Funds verified and link clicked: data from 'A' is copied to DB 'B' and 'A' is deleted. I have run similar processes with CSV output before and simply used //transfers old data to archive $transfer = mysql_query('INSERT INTO '.$archive.' SELECT * FROM '.$table) or die(mysql_error()); //empties existing table $query = mysql_query('TRUNCATE TABLE '.$table) or die(mysql_error()); but in those cases, ALL data returned was copied and deleted. I only want to copy and delete a single record. Any idea how to accomplish this?

    Read the article

  • Strange profiler behavior: same functions, different performances

    - by arthurprs
    I was learning to use gprof and then i got weird results for this code: int one(int a, int b) { return a / (b + 1); } int two(int a, int b) { return a / (b + 1); } int main() { for (int i = 1; i < 30000000; i++) { two(i, i * 2); one(i, i * 2); } return 0; } and this is the profiler output % cumulative self self total time seconds seconds calls ns/call ns/call name 48.39 0.90 0.90 29999999 30.00 30.00 one(int, int) 40.86 1.66 0.76 29999999 25.33 25.33 two(int, int) 10.75 1.86 0.20 main If i call one then two the result is the inverse, two takes more time than one both are the same functions, but the first calls always take less time then the second Why is that? Note: The assembly code is exactly the same and code is being compiled with no optimizations

    Read the article

  • Are conditional subqueries optimized out, if the condition is false?

    - by Tobias Schulte
    I have a table foo and a table bar, where each foo might have a bar (and a bar might belong to multiple foos). Now I need to select all foos with a bar. My sql looks like this SELECT * FROM foo f WHERE [...] AND ($param IS NULL OR (SELECT ((COUNT(*))>0) FROM bar b WHERE f.bar = b.id)) with $param being replaced at runtime. The question is: Will the subquery be executed even if param is null, or will the dbms optimize the subquery out? We are using mysql, mssql and oracle. Is there a difference between these regarding the above?

    Read the article

  • How To Securly Store Data In MySQL Using AES_ENCRYPT

    - by Justin
    We are storing sensitive data in MySQL, and I want to use AES_ENCRYPT(data, 'my-secret-key-here') which works great. My biggest question is how do I secure the key? Previously I just wast storing the key in a web PHP file, so something like: define("ENCRYPTION_KEY", 'my-secret-key-here'); This really doesn't work though, as our MySQL server and web server are the same physical machine, so if somebody gains access to the server, they can get both the encrypted data stored in MySQL and the key. Any ideas? I am thinking I need to move the key to a separate server, and read it in remotely. Or, what about generating the encryption key dynamically for each piece of data. For example taking the customer_id and running md5 on it, and then using that as the key.

    Read the article

  • How to speed up drawing of scaled image? Audio playback chokes during window resize.

    - by Paperflyer
    I am writing an audio player for OSX. One view is a custom view that displays a waveform. The waveform is stored as a instance variable of type NSImage with an NSBitmapImageRep. The view also displays a progress indicator (a thick red line). Therefore, it is updated/redrawn every 30 milliseconds. Since it takes a rather long time to recalculate the image, I do that in a background thread after every window resize and update the displayed image once the new image is ready. In the meantime, the original image is scaled to fit the view like this: // The drawing rectangle is slightly smaller than the view, defined by // the two margins. NSRect drawingRect; drawingRect.origin = NSMakePoint(sideEdgeMarginWidth, topEdgeMarginHeight); drawingRect.size = NSMakeSize([self bounds].size.width-2*sideEdgeMarginWidth, [self bounds].size.height-2*topEdgeMarginHeight); [waveform drawInRect:drawingRect fromRect:NSZeroRect operation:NSCompositeSourceOver fraction:1]; The view makes up the biggest part of the window. During live resize, audio starts choking. Selecting the "big" graphic card on my Macbook Pro makes it less bad, but not by much. CPU utilization is somewhere around 20-40% during live resizes. Instruments suggests that rescaling/redrawing of the image is the problem. Once I stop resizing the window, CPU utilization goes down and audio stops glitching. I already tried to disable image interpolation to speed up the drawing like this: [[NSGraphicsContext currentContext] setImageInterpolation:NSImageInterpolationNone]; That helps, but audio still chokes during live resizes. Do you have an idea how to improve this? The main thing is to prevent the audio from choking.

    Read the article

  • Assigning data to an <li> element?

    - by user246114
    Hi, I am generating some list items as a result of a search, and I want to attach some data to each list element from the search (possibly a bad idea to merge ui and data), but now curious about it. I am doing this: var element = $("<li>Hello</li>); element.mydata = "foo"; element.appendTo("#panelParent"); so I'm just assigning my stuff to element.mydata. My click handler reports that no such data exists for the element when clicked: $('#panelParent').delegate('li', 'click', function() { // this.mydata is undefined. }); where did it go to? I could keep the data external to the a list item element, was wondering if there's a convenient way like this to just keep it bound though? Thanks

    Read the article

  • How to store data which contains quotes in MySQL

    - by Nitz
    In one of my forms I use the rich text editor from Yahoo!. Now i want to store the data from that textarea in a MySQL database. The user can enter anything in that textarea, e.g. many double or single quotes. How can I store that data? Normally we store by adding that data in one variable and then put that in sql, but the quotes cause problems.

    Read the article

  • Looking for a fast hash-function.

    - by Julian
    Hello, I'm looking for a special hash-function. Let's say I have a large list of strings, if I order them by their hash-values they should be ordered quasi randomly. The most important point is: it must be super fast. I've tried md5 and sha1 and they're using to much cpu power. Clashes are not a problem. I'm using javascript, so it shouldn't be too complicated to implement.

    Read the article

  • Are doubles faster than floats in c#?

    - by Trap
    I'm writing an application which reads large arrays of floats and performs some simple operations with them. I'm using floats because I thought it'd be faster than doubles, but after doing some research I've found that there's some confusion about this topic. Can anyone elaborate on this? Thanks.

    Read the article

  • is it possible to store server returned json data in jqgrid to display columnnames models data dynamically for every request?

    - by user1768246
    is it possible to store server returned json data in jqgrid to display columnnames models data dynamically for every request ? $("#grid").jqGrid({ type: "GET", url: "", var columnNames = $("#grid")[0].p.colNames, var columnModel = $("#grid")[0].p.colNames, var columnData = $("#grid")[0].p.colNames, datatype: 'jsonstring', datastr: columnData, colModel: columnModel, jsonReader: { root: 'innerWrapper.rows', page: "result.gridData.outerWrapper.page", total: "result.gridData.outerWrapper.total", records: "result.gridData.outerWrapper.total", repeatitems: false, }, gridview: true, pager: "pager", height: "auto", rowNum: 10, width:"auto", height:"auto", rowList: [10, 20, 30,40], viewrecords: true, caption:"Graph Data", rownumbers: true, });

    Read the article

  • Optimizing Code

    - by Claudiu
    You are given a heap of code in your favorite language which combines to form a rather complicated application. It runs rather slowly, and your boss has asked you to optimize it. What are the steps you follow to most efficiently optimize the code? What strategies have you found to be unsuccessful when optimizing code? Re-writes: At what point do you decide to stop optimizing and say "This is as fast as it'll get without a complete re-write." In what cases would you advocate a simple complete re-write anyway? How would you go about designing it?

    Read the article

  • Problem with Refreshing data in ExpendableListView

    - by -providerivan.longin1
    Hi! My problem is when I want to refresh data in ExpendableListView while being in that current activity. I create adapter and when I want to add new data to list I call again constructor of that adapter(it is my private variable) with all new data....and then I call onContentChanged() method to redraw my list. But what happens is that I cant expand my list any more...like it is blocked or something and logcat isn't saying anything... This is the code that i call after setting new data in arraylists and maps: mAdapter = new MyExpandableListAdapter( this, groupData, R.layout.contact_list_parent, new String[] { NAME ,NUM_PHOTOS},//NUM_PHOTOS new int[] { R.id.rowText1, R.id.rowText2, R.id.photoAlbumImg }, childData, R.layout.contact_list_child, new String[] { NAME,NUM_PHOTOS}, //NUM_PHOTOS new int[] { R.id.rowText1, R.id.rowText2, R.id.photoAlbumImg } ); this.onContentChanged(); If anyone knows answer to this question please help me:) Thanks.

    Read the article

  • Why is my regex so much slower compiled than interpreted ?

    - by miket2e
    I have a large and complex C# regex that runs OK when interpreted, but is a bit slow. I'm trying to speed this up by setting RegexOptions.Compiled, and this seems to take about 30 seconds for the first time and instantly after that. I'm trying to negate this by compiling the regex to an assembly first, so my app can be as fast as possible. My problem is when the compiling delay takes place: Regex myComplexRegex = new Regex(regexText, RegexOptions.Compiled); MatchCollection matches = myComplexRegex.Matches(searchText); foreach (Match match in matches) // <--- when the one-time long delay kicks in { } This is making compiling to an assembly basically useless, as I still get the delay on the first foreach call. What I want is for all the compiling delay to be done in advance when I compile to the assembly, not when the user runs the app. Where am I going wrong ? (The code I'm using to compile to an assembly is similar to http://www.dijksterhuis.org/regular-expressions-advanced/ , if that's relevant ).

    Read the article

  • What GC parameters is a JVM running with?

    - by skaffman
    I'm still investigating issues I have with GC tuning (see prior question), which involves lots of reading and experimentation. Sun Java5+ JVMs attempt to automatically select the optimal GC strategy and parameters based on their environment, which is great, but I can't figure out how to query the running JVM to find out what those parameters are. Ideally, I'd like to see what values of the various GC-related -XX options are being used, as selected automatically by the VM. If I had that, I could have a baseline to begin tweaking. Anyone know to recover these values from a running VM?

    Read the article

  • Extract data from uint8 to double

    - by HADJ AMOR HASSEN
    I have a C function receiving a uint8 pointer with another parameter which is its size (number of bytes). I want to extract double data from this buffer. Here is my code: Write(uint8* data, uint8 size) /* data and size are given by a callback to my function)*/ { double d; for (i = 0; i < size; i++) { d = ((double*)&data)[i]; printf(" d = %d\n"); } } The problem is that I am not receiving what I am sending within an external hardware. I guess that my cast is wrong. I tried other methods but without any good result. I am still not able to get what I send.

    Read the article

  • XNA 2D/3D Drawing method?

    - by Adir
    What would be a better parctice, writing the drawing method inside the GameObject class or in the Game class? GameObject obj = new GameObject(); obj.Draw(); Or GameObject obj = new GameObject(); DrawGameObject(obj);

    Read the article

  • Best practice for avoiding locks on a heavily read table?

    - by Luiggi
    Hi, I have a big database (~4GB), with 2 large tables (~3M records) having ~180K SELECTs/hour, ~2k UPDATEs/hour and ~1k INSERTs+DELETEs/hour. What would be the best practice to guarantee no locks for the reading tasks while inserting/updating/deleting? I was thinking about using a NOLOCK hint, but there is so much discussed about this (is good, is bad, it depends) that I'm a bit lost. I must say I've tried this in a dev environment and I didn't find any problems, but I don't want to put it on production until I get some feedback... Thank you! Luiggi

    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 | 440 441 442 443 444 445 446 447 448 449 450 451  | Next Page >