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  • How do I move an Amazon micro instance to a small instance?

    - by Navetz
    I want to move my instance to a micro instance to a small instance but when I try to launch a new AMI based on my Micro instance AMI it only gives me the option for 64 bit instances. My initial ami is based off an ubuntu 10.04 image. Is it not possible to move between 64 bit and 32 bit instance? Would it be possible to use a load balancer to have a 32bit instance and a 64bit instance work together? I have a website/web app that I will be uploading huge volumes of data to. I will be starting with 65gigs of images and then moving up to 100+ gigs of images. I am not sure which instance type would be best for this. I was going to use a load balancer and auto scaling to increase the number of instance when the load is high. Also when using a load balancer, does one of the AMI instance become the primary image and the rest act as clones of it?

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  • How can I turn a string of text into a BigInteger representation for use in an El Gamal cryptosystem

    - by angstrom91
    I'm playing with the El Gamal cryptosystem, and my goal is to be able to encipher and decipher long sequences of text. I have come up with a method that works for short sequences, but does not work for long sequences, and I cannot figure out why. El Gamal requires the plaintext to be an integer. I have turned my string into a byte[] using the .getBytes() method for Strings, and then created a BigInteger out of the byte[]. After encryption/decryption, I turn the BigInteger into a byte[] using the .toByteArray() method for BigIntegers, and then create a new String object from the byte[]. This works perfectly when i call ElGamalEncipher with strings up to 129 characters. With 130 or more characters, the output produced is garbled. Can someone suggest how to solve this issue? Is this an issue with my method of turning the string into a BigInteger? If so, is there a better way to turn my string of text into a BigInteger and back? Below is my encipher/decipher code. public static BigInteger[] ElGamalEncipher(String plaintext, BigInteger p, BigInteger g, BigInteger r) { // returns a BigInteger[] cipherText // cipherText[0] is c // cipherText[1] is d BigInteger[] cipherText = new BigInteger[2]; BigInteger pText = new BigInteger(plaintext.getBytes()); // 1: select a random integer k such that 1 <= k <= p-2 BigInteger k = new BigInteger(p.bitLength() - 2, sr); // 2: Compute c = g^k(mod p) BigInteger c = g.modPow(k, p); // 3: Compute d= P*r^k = P(g^a)^k(mod p) BigInteger d = pText.multiply(r.modPow(k, p)).mod(p); // C =(c,d) is the ciphertext cipherText[0] = c; cipherText[1] = d; return cipherText; } public static String ElGamalDecipher(BigInteger c, BigInteger d, BigInteger a, BigInteger p) { //returns the plaintext enciphered as (c,d) // 1: use the private key a to compute the least non-negative residue // of an inverse of (c^a)' (mod p) BigInteger z = c.modPow(a, p).modInverse(p); BigInteger P = z.multiply(d).mod(p); byte[] plainTextArray = P.toByteArray(); String output = null; try { output = new String(plainTextArray, "UTF8"); } catch (Exception e) { } return output; }

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  • Streamed mp3 only plays for 1 second

    - by angel6
    Hi, I'm using the plaympeg.c (modified) code of smpeg as a media player. I've got ffserver running as a streaming server. I'm a streaming an mp3 file over http. But when I run plaympeg.c, it plays the streamed file only for a second. When I run plaympeg again, it starts off from where it left and plays for 1 second. Does anyone know why this happens an how to fix it? I've tested it out on WMP and it plays the entire file in one go. So, i guess it's not a problem with the streaming or ffserver.conf include include include include /* #ifdef unix */ include include include include include include include define NET_SUPPORT /* General network support */ define HTTP_SUPPORT /* HTTP support */ ifdef NET_SUPPORT include include include include endif include "smpeg.h" ifdef NET_SUPPORT int tcp_open(char * address, int port) { struct sockaddr_in stAddr; struct hostent * host; int sock; struct linger l; memset(&stAddr,0,sizeof(stAddr)); stAddr.sin_family = AF_INET ; stAddr.sin_port = htons(port); if((host = gethostbyname(address)) == NULL) return(0); stAddr.sin_addr = *((struct in_addr *) host-h_addr_list[0]) ; if((sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) return(0); l.l_onoff = 1; l.l_linger = 5; if(setsockopt(sock, SOL_SOCKET, SO_LINGER, (char*) &l, sizeof(l)) < 0) return(0); if(connect(sock, (struct sockaddr *) &stAddr, sizeof(stAddr)) < 0) return(0); return(sock); } ifdef HTTP_SUPPORT int http_open(char * arg) { char * host; int port; char * request; int tcp_sock; char http_request[1024]; char c; printf("\nin http_open passed parameter = %s\n",arg); /* Check for URL syntax */ if(strncmp(arg, "http://", strlen("http://"))) return(0); /* Parse URL */ port = 80; host = arg + strlen("http://"); if((request = strchr(host, '/')) == NULL) return(0); request++ = 0; if(strchr(host, ':') != NULL) / port is specified */ { port = atoi(strchr(host, ':') + 1); *strchr(host, ':') = 0; } /* Open a TCP socket */ if(!(tcp_sock = tcp_open(host, port))) { perror("http_open"); return(0); } /* Send HTTP GET request */ sprintf(http_request, "GET /%s HTTP/1.0\r\n" "User-Agent: Mozilla/2.0 (Win95; I)\r\n" "Pragma: no-cache\r\n" "Host: %s\r\n" "Accept: /\r\n" "\r\n", request, host); send(tcp_sock, http_request, strlen(http_request), 0); /* Parse server reply */ do read(tcp_sock, &c, sizeof(char)); while(c != ' '); read(tcp_sock, http_request, 4*sizeof(char)); http_request[4] = 0; if(strcmp(http_request, "200 ")) { fprintf(stderr, "http_open: "); do { read(tcp_sock, &c, sizeof(char)); fprintf(stderr, "%c", c); } while(c != '\r'); fprintf(stderr, "\n"); return(0); } return(tcp_sock); } endif endif void update(SDL_Surface *screen, Sint32 x, Sint32 y, Uint32 w, Uint32 h) { if ( screen-flags & SDL_DOUBLEBUF ) { SDL_Flip(screen); } } /* Flag telling the UI that the movie or song should be skipped */ int done; void next_movie(int sig) { done = 1; } int main(int argc, char *argv[]) { int use_audio, use_video; int fullscreen; int scalesize; int scale_width, scale_height; int loop_play; int i, pause; int volume; Uint32 seek; float skip; int bilinear_filtering; SDL_Surface *screen; SMPEG *mpeg; SMPEG_Info info; char *basefile; SDL_version sdlver; SMPEG_version smpegver; int fd; char buf[32]; int status; printf("\nchecking command line options "); /* Get the command line options */ use_audio = 1; use_video = 1; fullscreen = 0; scalesize = 1; scale_width = 0; scale_height = 0; loop_play = 0; volume = 100; seek = 0; skip = 0; bilinear_filtering = 0; fd = 0; for ( i=1; argv[i] && (argv[i][0] == '-') && (argv[i][1] != 0); ++i ) { if ( strcmp(argv[i], "--fullscreen") == 0 ) { fullscreen = 1; } else if ((strcmp(argv[i], "--seek") == 0)||(strcmp(argv[i], "-S") == 0)) { ++i; if ( argv[i] ) { seek = atol(argv[i]); } } else if ((strcmp(argv[i], "--volume") == 0)||(strcmp(argv[i], "-v") == 0)) { ++i; if (i >= argc) { fprintf(stderr, "Please specify volume when using --volume or -v\n"); return(1); } if ( argv[i] ) { volume = atoi(argv[i]); } if ( ( volume < 0 ) || ( volume 100 ) ) { fprintf(stderr, "Volume must be between 0 and 100\n"); volume = 100; } } else { fprintf(stderr, "Warning: Unknown option: %s\n", argv[i]); } } printf("\nuse video = %d, use audio = %d\n",use_video, use_audio); printf("\ngoing to check input parameters\n"); if defined(linux) || defined(FreeBSD) /* Plaympeg doesn't need a mouse */ putenv("SDL_NOMOUSE=1"); endif /* Play the mpeg files! */ status = 0; for ( ; argv[i]; ++i ) { /* Initialize SDL */ if ( use_video ) { if ((SDL_Init(SDL_INIT_VIDEO) < 0) || !SDL_VideoDriverName(buf, 1)) { fprintf(stderr, "Warning: Couldn't init SDL video: %s\n", SDL_GetError()); fprintf(stderr, "Will ignore video stream\n"); use_video = 0; } printf("\ninitialised video\n"); } if ( use_audio ) { if ((SDL_Init(SDL_INIT_AUDIO) < 0) || !SDL_AudioDriverName(buf, 1)) { fprintf(stderr, "Warning: Couldn't init SDL audio: %s\n", SDL_GetError()); fprintf(stderr, "Will ignore audio stream\n"); use_audio = 0; } } /* Allow Ctrl-C when there's no video output */ signal(SIGINT, next_movie); printf("\nchecking defined supports\n"); /* Create the MPEG stream */ ifdef NET_SUPPORT printf("\ndefined NET_SUPPORT\n"); ifdef HTTP_SUPPORT printf("\ndefined HTTP_SUPPORT\n"); /* Check if source is an http URL */ printf("\nabout to call http_open\n"); printf("\nhere we go\n"); if((fd = http_open(argv[i])) != 0) mpeg = SMPEG_new_descr(fd, &info, use_audio); else endif endif { if(strcmp(argv[i], "-") == 0) /* Use stdin for input */ mpeg = SMPEG_new_descr(0, &info, use_audio); else mpeg = SMPEG_new(argv[i], &info, use_audio); } if ( SMPEG_error(mpeg) ) { fprintf(stderr, "%s: %s\n", argv[i], SMPEG_error(mpeg)); SMPEG_delete(mpeg); status = -1; continue; } SMPEG_enableaudio(mpeg, use_audio); SMPEG_enablevideo(mpeg, use_video); SMPEG_setvolume(mpeg, volume); /* Print information about the video */ basefile = strrchr(argv[i], '/'); if ( basefile ) { ++basefile; } else { basefile = argv[i]; } if ( info.has_audio && info.has_video ) { printf("%s: MPEG system stream (audio/video)\n", basefile); } else if ( info.has_audio ) { printf("%s: MPEG audio stream\n", basefile); } else if ( info.has_video ) { printf("%s: MPEG video stream\n", basefile); } if ( info.has_video ) { printf("\tVideo %dx%d resolution\n", info.width, info.height); } if ( info.has_audio ) { printf("\tAudio %s\n", info.audio_string); } if ( info.total_size ) { printf("\tSize: %d\n", info.total_size); } if ( info.total_time ) { printf("\tTotal time: %f\n", info.total_time); } /* Set up video display if needed */ if ( info.has_video && use_video ) { const SDL_VideoInfo *video_info; Uint32 video_flags; int video_bpp; int width, height; /* Get the "native" video mode */ video_info = SDL_GetVideoInfo(); switch (video_info->vfmt->BitsPerPixel) { case 16: case 24: case 32: video_bpp = video_info->vfmt->BitsPerPixel; break; default: video_bpp = 16; break; } if ( scale_width ) { width = scale_width; } else { width = info.width; } width *= scalesize; if ( scale_height ) { height = scale_height; } else { height = info.height; } height *= scalesize; video_flags = SDL_SWSURFACE; if ( fullscreen ) { video_flags = SDL_FULLSCREEN|SDL_DOUBLEBUF|SDL_HWSURFACE; } video_flags |= SDL_ASYNCBLIT; video_flags |= SDL_RESIZABLE; screen = SDL_SetVideoMode(width, height, video_bpp, video_flags); if ( screen == NULL ) { fprintf(stderr, "Unable to set %dx%d video mode: %s\n", width, height, SDL_GetError()); continue; } SDL_WM_SetCaption(argv[i], "plaympeg"); if ( screen->flags & SDL_FULLSCREEN ) { SDL_ShowCursor(0); } SMPEG_setdisplay(mpeg, screen, NULL, update); SMPEG_scaleXY(mpeg, screen->w, screen->h); } else { SDL_QuitSubSystem(SDL_INIT_VIDEO); } /* Set any special playback parameters */ if ( loop_play ) { SMPEG_loop(mpeg, 1); } /* Seek starting position */ if(seek) SMPEG_seek(mpeg, seek); /* Skip seconds to starting position */ if(skip) SMPEG_skip(mpeg, skip); /* Play it, and wait for playback to complete */ SMPEG_play(mpeg); done = 0; pause = 0; while ( ! done && ( pause || (SMPEG_status(mpeg) == SMPEG_PLAYING) ) ) { SDL_Event event; while ( use_video && SDL_PollEvent(&event) ) { switch (event.type) { case SDL_VIDEORESIZE: { SDL_Surface *old_screen = screen; SMPEG_pause(mpeg); screen = SDL_SetVideoMode(event.resize.w, event.resize.h, screen->format->BitsPerPixel, screen->flags); if ( old_screen != screen ) { SMPEG_setdisplay(mpeg, screen, NULL, update); } SMPEG_scaleXY(mpeg, screen-w, screen-h); SMPEG_pause(mpeg); } break; case SDL_KEYDOWN: if ( (event.key.keysym.sym == SDLK_ESCAPE) || (event.key.keysym.sym == SDLK_q) ) { // Quit done = 1; } else if ( event.key.keysym.sym == SDLK_RETURN ) { // toggle fullscreen if ( event.key.keysym.mod & KMOD_ALT ) { SDL_WM_ToggleFullScreen(screen); fullscreen = (screen-flags & SDL_FULLSCREEN); SDL_ShowCursor(!fullscreen); } } else if ( event.key.keysym.sym == SDLK_UP ) { // Volume up if ( volume < 100 ) { if ( event.key.keysym.mod & KMOD_SHIFT ) { // 10+ volume += 10; } else if ( event.key.keysym.mod & KMOD_CTRL ) { // 100+ volume = 100; } else { // 1+ volume++; } if ( volume 100 ) volume = 100; SMPEG_setvolume(mpeg, volume); } } else if ( event.key.keysym.sym == SDLK_DOWN ) { // Volume down if ( volume 0 ) { if ( event.key.keysym.mod & KMOD_SHIFT ) { volume -= 10; } else if ( event.key.keysym.mod & KMOD_CTRL ) { volume = 0; } else { volume--; } if ( volume < 0 ) volume = 0; SMPEG_setvolume(mpeg, volume); } } else if ( event.key.keysym.sym == SDLK_PAGEUP ) { // Full volume volume = 100; SMPEG_setvolume(mpeg, volume); } else if ( event.key.keysym.sym == SDLK_PAGEDOWN ) { // Volume off volume = 0; SMPEG_setvolume(mpeg, volume); } else if ( event.key.keysym.sym == SDLK_SPACE ) { // Toggle play / pause if ( SMPEG_status(mpeg) == SMPEG_PLAYING ) { SMPEG_pause(mpeg); pause = 1; } else { SMPEG_play(mpeg); pause = 0; } } else if ( event.key.keysym.sym == SDLK_RIGHT ) { // Forward if ( event.key.keysym.mod & KMOD_SHIFT ) { SMPEG_skip(mpeg, 100); } else if ( event.key.keysym.mod & KMOD_CTRL ) { SMPEG_skip(mpeg, 50); } else { SMPEG_skip(mpeg, 5); } } else if ( event.key.keysym.sym == SDLK_LEFT ) { // Reverse if ( event.key.keysym.mod & KMOD_SHIFT ) { } else if ( event.key.keysym.mod & KMOD_CTRL ) { } else { } } else if ( event.key.keysym.sym == SDLK_KP_MINUS ) { // Scale minus if ( scalesize > 1 ) { scalesize--; } } else if ( event.key.keysym.sym == SDLK_KP_PLUS ) { // Scale plus scalesize++; } else if ( event.key.keysym.sym == SDLK_f ) { // Toggle filtering on/off if ( bilinear_filtering ) { SMPEG_Filter *filter = SMPEGfilter_null(); filter = SMPEG_filter( mpeg, filter ); filter-destroy(filter); bilinear_filtering = 0; } else { SMPEG_Filter *filter = SMPEGfilter_bilinear(); filter = SMPEG_filter( mpeg, filter ); filter-destroy(filter); bilinear_filtering = 1; } } break; case SDL_QUIT: done = 1; break; default: break; } } SDL_Delay(1000/2); } SMPEG_delete(mpeg); } SDL_Quit(); if defined(HTTP_SUPPORT) if(fd) close(fd); endif return(status); }

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  • Data loss when downloading data from LDAP server

    - by Ricky D'Amelio
    Hi there. This question comes from a previous one I asked about handling NSData objects: http://stackoverflow.com/questions/2453785/converting-nsdata-to-an-nsstring-representation-is-failing. I have reached the point where I am taking an NSImage, turning it into NSData and uploading those data bytes to the LDAP server. I am doing this like so; //connected successfully to LDAP server above... struct berval photo_berval; struct berval *jpegPhoto_values[2]; photo_berval.bv_len = [photo length]; photo_berval.bv_val = [photo bytes]; jpegPhoto_values[0] = &photo_berval; jpegPhoto_values[1] = NULL; mod.mod_type = "jpegPhoto"; mod.mod_op = LDAP_MOD_REPLACE|LDAP_MOD_BVALUES; mod.mod_bvalues = jpegPhoto_values; mods[0] = &mod; mods[1] = NULL; //perform the modify operation rc = ldap_modify_ext_s(ld, givenModifyEntry, mods, NULL, NULL); That happens with no errors, and you can see a big blob of data when you're in the command line. My problem is, when I go to access the same data at a later stage, I am getting an image file back that's about 120 times smaller than the original image. //find the jpegPhoto attribute photoA = ldap_first_attribute(ld, photoE, &photoBer); while (strcasecmp(photoA, "jpegphoto") != 0) { photoA = ldap_next_attribute(ld, photoE, photoBer); } //get the value of the attribute if ((list_of_photos = ldap_get_values_len(ld, photoE, photoA)) != NULL) { //get the first JPEG photo_data = *list_of_photos[0]; selectedPictureData = [NSData dataWithBytes:&photo_data length:sizeof(photo_data)]; [selectedPictureData writeToFile:@"/Users/username/Desktop/Photo 2.jpg" atomically:YES]; NSLog (@"%@", selectedPictureData); Has anyone successfully done this before or can anyone see what I might be doing wrong? I appreciate anyone's help. Sorry to post so many questions! Ricky.

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  • Maintain order of messages via proxies to app servers

    - by David Turner
    Hi, I am receiving messages from a 3rd party via a http post, and it is important that the order the messages hit our infrastructure is maintained through the load balancers and proxies until it hits our application server. Quick Diagram. (proxies in place due to security requirements.) [ACE load balancer] - [2 proxies] - [Application Servers] or maybe [ACE load balancer] - [2 proxies] - [ACE load balancer] - [Application Servers] My idea was that I would setup the load balancers in active-passive mode, to force all messages to use one proxy, and then both the proxies would hit a second load balancer that would be configured in active passive to hit one application server. Whilst the above is not ideal, it does give me resilience, and once the message is in my app servers, I enter a stateless world, and load balance across both nodes of my cluster. However, I am concerned that even a single proxy could send messages out of order, perhaps if 2 messages are recived very close together, message 2 might get processed faster than message 1. Is this possible? Likely? Is there a simple open source proxy (MOD_PROXY?) that can be easily configured to just pass messages through it, and to guarantee to send the messages through in the order they are received. If so which, and finally links to how I should configure it would be great. In fact any links to articles around avoiding "out of order" messages using hardware would be gratefully received. Thanks, ps for those that are interested, the app is a java spring integration application currently on a appliation server.

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  • What is causing Apache2 to display PHP as plain text in this config file?

    - by rxgx
    I am trying to run PHP and Rails in the same virtual host, however, PHP is being displayed as plain/text. When I create a test host without all the rewrites and proxy-ing, Apache2 will process the PHP as desired. Where in my config file have I gone wrong? <VirtualHost *:80> #ServerName staging.domain.com #ServerAlias www.domain.com DocumentRoot /home/demo/vhosts/domain/public <Directory /> Options FollowSymLinks AllowOverride None </Directory> <Directory /home/demo/vhosts/domain/public> Options Indexes FollowSymLinks MultiViews AllowOverride None Order allow,deny allow from all </Directory> RewriteEngine On <Proxy balancer://thinservers> BalancerMember http://127.0.0.1:5000 BalancerMember http://127.0.0.1:5001 BalancerMember http://127.0.0.1:5002 </Proxy> # Redirect all non-static requests to thin RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_FILENAME} !-f RewriteRule ^/(.*)$ balancer://thinservers%{REQUEST_URI} [P,QSA,L] ProxyPass / balancer://thinservers/ ProxyPassReverse / balancer://thinservers/ ProxyPreserveHost on <Proxy *> Order deny,allow Allow from all </Proxy> # Custom log file locations ErrorLog /home/demo/vhosts/domain/log/error.log CustomLog /home/demo/vhosts/domain/log/access.log combined </VirtualHost>

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  • How can I superimpose modified loess lines on a ggplot2 qplot?

    - by briandk
    Background Right now, I'm creating a multiple-predictor linear model and generating diagnostic plots to assess regression assumptions. (It's for a multiple regression analysis stats class that I'm loving at the moment :-) My textbook (Cohen, Cohen, West, and Aiken 2003) recommends plotting each predictor against the residuals to make sure that: The residuals don't systematically covary with the predictor The residuals are homoscedastic with respect to each predictor in the model On point (2), my textbook has this to say: Some statistical packages allow the analyst to plot lowess fit lines at the mean of the residuals (0-line), 1 standard deviation above the mean, and 1 standard deviation below the mean of the residuals....In the present case {their example}, the two lines {mean + 1sd and mean - 1sd} remain roughly parallel to the lowess {0} line, consistent with the interpretation that the variance of the residuals does not change as a function of X. (p. 131) How can I modify loess lines? I know how to generate a scatterplot with a "0-line,": # First, I'll make a simple linear model and get its diagnostic stats library(ggplot2) data(cars) mod <- fortify(lm(speed ~ dist, data = cars)) attach(mod) str(mod) # Now I want to make sure the residuals are homoscedastic qplot (x = dist, y = .resid, data = mod) + geom_smooth(se = FALSE) # "se = FALSE" Removes the standard error bands But does anyone know how I can use ggplot2 and qplot to generate plots where the 0-line, "mean + 1sd" AND "mean - 1sd" lines would be superimposed? Is that a weird/complex question to be asking?

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  • From where starts the process' memory space and where does it end?

    - by nhaa123
    Hi, I'm trying to dump memory from my application where the variables lye. Here's the function: void MyDump(const void *m, unsigned int n) { const unsigned char *p = reinterpret_cast<const unsigned char *(m); char buffer[16]; unsigned int mod = 0; for (unsigned int i = 0; i < n; ++i, ++mod) { if (mod % 16 == 0) { mod = 0; std::cout << " | "; for (unsigned short j = 0; j < 16; ++j) { switch (buffer[j]) { case 0xa: case 0xb: case 0xd: case 0xe: case 0xf: std::cout << " "; break; default: std::cout << buffer[j]; } } std::cout << "\n0x" << std::setfill('0') << std::setw(8) << std::hex << (long)i << " | "; } buffer[i % 16] = p[i]; std::cout << std::setw(2) << std::hex << static_cast<unsigned int(p[i]) << " "; if (i % 4 == 0 && i != 1) std::cout << " "; } } Now, how can I know from which address starts my process memory space, where all the variables are stored? And how do I now, how long the area is? For instance: MyDump(0x0000 /* <-- Starts from here? */, 0x1000 /* <-- This much? */); Best regards, nhaa123

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  • Scalability 101: How can I design a scalable web application using PHP?

    - by Legend
    I am building a web-application and have a couple of quick questions. From what I learnt, one should not worry about scalability when initially building the app and should only start worrying when the traffic increases. However, this being my first web-application, I am not quite sure if I should take an approach where I design things in an ad-hoc manner and later "fix" them. I have been reading stories about how people start off with an app that gets millions of users in a week or two. Not that I will face the same situation but I can't help but wonder, how do these people do it? Currently, I bought a shared hosting account on Lunarpages and that got me started in building and testing the application. However, I am interested in learning how to build the same application in a scalable-manner using the cloud, for instance, Amazon's EC2. From my understanding, I can see a couple of components: There is a load balancer that first receives requests and then decides where to route each request This request is then handled by a server replica that then processes the request and updates (if required) the database and sends back the response to the client If a similar request comes in, then a caching mechanism like memcached kicks into picture and returns objects from the cache A blackbox that handles database replication Specifically, I am trying to do the following: Setting up a load balancer (my homework revealed that HAProxy is one such load balancer) Setting up replication so that databases can be synchronized Using memcached Configuring Apache to work with multiple web servers Partitioning application to use Amazon EC2 and Amazon S3 (my application is something that will need great deal of storage) Finally, how can I avoid burning myself when using Amazon services? Because this is just a learning phase, I can probably do with 2-3 servers with a simple load balancer and replication but until I want to avoid paying loads of money accidentally. I am able to find resources on individual topics but am unable to find something that starts off from the big picture. Can someone please help me get started?

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  • IIS6 Log time recording problems

    - by Hafthor
    On three separate occasions on two separate servers at nearly the same times, 6.9 hours seemingly went by without any data being written to the IIS logs, but, on closer inspection, it appears that it was all recorded all at once. Here's the facts as I know them: Windows Server 2003 R2 w/ IIS6 Logging using GMT, server local time GMT-7. Application was still operating and I have SQL data to prove that Time gaps appear in log file, not across two # headers appear at gap Load balancer pings every 30 seconds No caching Here's info on a particular case: an entry appears for 2009-09-21 18:09:27 then #headers the next entry is for 2009-09-22 01:21:54, and so are the next 1600 entries in this log file and 370 in the next log file. about half of the ~2000 entries on 2009-09-22 01:21:54 are load balancer pings (est. at 2/min for 6.9hrs = 828 pings) then entries are recorded as normal. I believe that these events may coincide with me deploying an ASP.NET application update into those machines. Here's some relevant content from the logs in question: ex090921.log line 3684 2009-09-21 17:54:40 GET /ping.aspx - 80 404 0 0 3733 122 0 2009-09-21 17:55:11 GET /ping.aspx - 80 404 0 0 3733 122 0 2009-09-21 17:55:42 GET /ping.aspx - 80 404 0 0 3733 122 0 2009-09-21 17:56:13 GET /ping.aspx - 80 404 0 0 3733 122 0 2009-09-21 17:56:45 GET /ping.aspx - 80 404 0 0 3733 122 0 #Software: Microsoft Internet Information Services 6.0 #Version: 1.0 #Date: 2009-09-21 18:04:37 #Fields: date time cs-method cs-uri-stem cs-uri-query s-port sc-status sc-substatus sc-win32-status sc-bytes cs-bytes time-taken 2009-09-22 01:04:06 GET /ping.aspx - 80 404 0 0 3733 122 3078 2009-09-22 01:04:06 GET /ping.aspx - 80 404 0 0 3733 122 109 2009-09-22 01:04:06 GET /ping.aspx - 80 200 0 0 278 122 3828 2009-09-22 01:04:06 GET /ping.aspx - 80 200 0 0 278 122 0 2009-09-22 01:04:06 GET /ping.aspx - 80 200 0 0 278 122 0 ... continues until line 5449 2009-09-22 01:04:06 GET /ping.aspx - 80 200 0 0 277 122 0 <eof> ex090922.log #Software: Microsoft Internet Information Services 6.0 #Version: 1.0 #Date: 2009-09-22 00:00:16 #Fields: date time cs-method cs-uri-stem cs-uri-query s-port sc-status sc-substatus sc-win32-status sc-bytes cs-bytes time-taken 2009-09-22 01:04:06 GET /ping.aspx - 80 200 0 0 277 122 0 2009-09-22 01:04:06 GET /ping.aspx - 80 200 0 0 277 122 0 ... continues until line 367 2009-09-22 01:04:06 GET /ping.aspx - 80 200 0 0 277 122 0 2009-09-22 01:04:30 GET /ping.aspx - 80 200 0 0 277 122 0 ... back to normal behavior Note the seemingly correct date/time written to the #header of the new log file. Also note that /ping.aspx returned 404 then switched to 200 just as the problem started. I rename the "I'm alive page" so the load balancer stops sending requests to the server while I'm working on it. What you see here is me renaming it back so the load balancer will use the server. So, this problem definitely coincides with me re-enabling the server. Any ideas?

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  • Is there a way to route all traffic from Android through a proxy/tunnel to my Tomato router?

    - by endolith
    I'd like to be able to connect my Android phone to public Wi-Fi points with unencrypted connections, but People can see what I'm doing by intercepting my radio transmissions People who own the access point can see what I'm doing. There are tools like WeFi and probably others to automatically connect to access points, but I don't trust random APs. I'd like all my traffic to go through an encrypted tunnel to my home router, and from there out to the Internet. I've done such tunnels from other computers with SSH/SOCKS and PPTP before. Is there any way to do this with Android? I've asked the same question on Force Close, so I'll change this question to be about both sides of the tunnel. More specifically: My phone now has CyanogenMod 4.2.3 My router currently has Tomato Version 1.25 I'm willing to change the router firmware, but I was having issues with DD-WRT disconnecting, which is why I'm using Tomato. Some possible solutions: SSH with dynamic SOCKS proxy: Android supposedly supports this through ConnectBot, but I don't know how to get it to route all traffic. Tomato supports this natively. I've been using this with MyEntunnel for my web browsing at work. Requires setting up each app to go through the proxy, though. PPTP: Android supports this natively. Tomato does not support this, unless you get the jyavenard mod and compile it? I previously used PPTP for web browsing at work and in China because it's native in Windows and DD-WRT. After a while I started having problems with it, then I started having problems with DD-WRT, so I switched to the SSH tunnel instead. Also it supposedly has security flaws, but I don't understand how big of a problem it is. IPSec L2TP: Android (phone) and Windows (work/China) both support this natively I don't know of a router that does. I could run it on my computer using openswan, but then there are two points of failure. OpenVPN: CyanogenMod apparently includes this, and now has an entry to create a new OpenVPN in the normal VPN interface, but I have no idea how to configure it. TunnelDroid apparently handles some of this. Future versions will have native support in the VPN settings? Tomato does not support this, but there are mods that do? I don't know how to configure this, either. TomatoVPN roadkill mod SgtPepperKSU mod Thor mod I could also run a VPN server on my desktop, I guess, though that's less reliable and presumably slower than running it in the router itself. I could change the router firmware, but I'm wary of more fundamental things breaking. Tomato has been problem-free for the regular stuff. Related: Anyone set up a SSH tunnel to their (rooted) G1 for browsing?

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  • Tomcat - Spring Framework - MySQL, Load balancing design

    - by Mat Banik
    Lets say I have Spring Framework App that is running on Tomcat and uses MySQL database: What would be the best solution in this instance that would allow for sociability (price/performance/integration time)? More precisely: What would be on the Web Load balancer box, and who should be the tomcat web server clustered? What would be on the Database Load balancer box and how should be the database servers clustered? And if at all possible specific technical integration links would be of great help.

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  • HAProxy redirect HTTPS to HTTP

    - by tarnfeld
    I'm using HAProxy as a load balancer and i'd like to redirect any traffic that comes in on 443 (HTTPS) to 80 (HTTP). My site doesn't support HTTPS at all and i'd rather just redirect users than cause any SSL warnings in browsers. All I can find is using the redirect location <to> syntax, but as far as I can tell that requires me to hard code the hostname. The load balancer receives connections for various hostnames so would like to keep it relative.

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  • HTTPS request to a specific load-balanced virtual host (using Shibboleth for SSO)?

    - by Gary S. Weaver
    In one environment, we have three servers load balanced that have a single Tomcat instance on each, fronted by two different Apache virtual hosts. Each of those two virtual hosts (served by all three servers) has its own different load balancer. Internally, the first host (we'll call it barfoo) is served by port 443 (HTTPS) with its cert and the second host (we'll call it foobar) is served by port 1443 (HTTPS). When you hit foobar, it goes to the load balancer which is using IP affinity for that host, so you can easily test login/HTTPS on one of the servers serving foobar, but not the others (because you keep getting that server for the lifetime of the LB session, iirc). In addition, each of the servers are using Shibboleth v2 for authN/SSO, using mod_shib (iirc). So, a normal request to foobar hits the LB, is directed to the 3rd server (and will do that from then on for as long as the LB session lasts), then Apache, then to the Shibboleth SP which looks at the request, makes you login via negotiation with the Shibboleth IdP, then you hit Apache again which in turn hits Tomcat, renders, and returns the response. (I'm leaving out some steps there.) We'd like to hit one of the individual servers (foobar-03.acme.org which we'll say has IP 1.2.3.4) via HTTPS (skipping the load balancer), so we at first try putting this in /etc/hosts: 1.2.3.4 foobar.acme.org But since foobar.acme.org is a secondary virtual host running on 1443, it attempts to get barfoo.acme.org rather than foobar.acme.org at port 1443 and see that the cert for barfoo.acme.org is invalid for this case since it doesn't match the request's host, foobar.acme.org. I thought an ssh tunnel might be easy enough, so I tried: ssh -L 7777:foobar-03.acme.org:1443 [email protected] I tried just hitting https://localhost:7777/webappname in a browser, but when the Shibboleth login is over, it again tries to redirect to barfoo.acme.org, which is the default host for 443, and we get into an infinite redirect loop. I then tried setting up an SSH tunnel with privileged port 443 locally going to 443 of foobar-03.acme.org as the hostname for that virtual host: sudo ssh -L 443:foobar-03.acme.org:1443 [email protected] I also edited /etc/hosts to add: 127.0.0.1 foobar.acme.org This finally worked and I was able to get the browser to hit the individual HTTPS host at https://foobar.acme.org/webappname, bypassing the load balancer. This was a bit of a pain and wouldn't work for everyone, due to the requirement to use the local 443 port and ssh to the server. Is there an easier way to browse to and log into an individual host in this case?

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  • PHP 5.2 to 5.3 not upgrading, no errors

    - by Webnet
    I'm following this guide: http://atik97.wordpress.com/2010/06/12/how-to-upgrade-to-php-5-3-in-ubuntu-9-10/ I've done all the steps, but it's still showing php 5.2.6 - any ideas? I have also tried -cgi instead of -cli, neither have any effect. update I've tried rebooting the server to see if that would have any effect and unfortunately it didn't update Output of dpkg -l *php*: Desired=Unknown/Install/Remove/Purge/Hold | Status=Not/Inst/Cfg-files/Unpacked/Failed-cfg/Half-inst/trig-aWait/Trig-pend |/ Err?=(none)/Hold/Reinst-required/X=both-problems (Status,Err: uppercase=bad) ||/ Name Version Description +++-=============================================-=============================================-========================================================================================================== un libapache2-mod-php4 <none> (no description available) ii libapache2-mod-php5 5.2.6.dfsg.1-3ubuntu4.6 server-side, HTML-embedded scripting language (Apache 2 module) un libapache2-mod-php5filter <none> (no description available) ii php-pear 5.2.6.dfsg.1-3ubuntu4.6 PEAR - PHP Extension and Application Repository un php4-cli <none> (no description available) un php4-dev <none> (no description available) un php4-mysql <none> (no description available) un php4-pear <none> (no description available) ii php5 5.2.6.dfsg.1-3ubuntu4.6 server-side, HTML-embedded scripting language (metapackage) ii php5-cgi 5.2.6.dfsg.1-3ubuntu4.6 server-side, HTML-embedded scripting language (CGI binary) ii php5-cli 5.2.6.dfsg.1-3ubuntu4.6 command-line interpreter for the php5 scripting language ii php5-common 5.2.6.dfsg.1-3ubuntu4.6 Common files for packages built from the php5 source ii php5-curl 5.2.6.dfsg.1-3ubuntu4.6 CURL module for php5 un php5-dev <none> (no description available) ii php5-gd 5.2.6.dfsg.1-3ubuntu4.6 GD module for php5 ii php5-imap 5.2.6-0ubuntu5.1 IMAP module for php5 un php5-json <none> (no description available) ii php5-mcrypt 5.2.6-0ubuntu2 MCrypt module for php5 ii php5-mysql 5.2.6.dfsg.1-3ubuntu4.6 MySQL module for php5 un php5-mysqli <none> (no description available) ii php5-xsl 5.2.6.dfsg.1-3ubuntu4.6 XSL module for php5 un phpapi-20060613+lfs <none> (no description available) ii phpmyadmin 4:3.1.2-1ubuntu0.2 MySQL web administration tool update The following commands and their outputs: grep php53 /etc/apt/sources.list deb http://php53.dotdeb.org stable all deb-src http://php53.dotdeb.org stable all apt-cache search -f "libapache2-mod-php5" http://pastebin.com/XNXdsXYC update I've updated the question with more details on installed packages.

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  • IIS6 Log time recording problems

    - by Hafthor
    On three separate occasions on two separate servers at nearly the same times, 6.9 hours seemingly went by without any data being written to the IIS logs, but, on closer inspection, it appears that it was all recorded all at once. Here's the facts as I know them: Windows Server 2003 R2 w/ IIS6 Logging using GMT, server local time GMT-7. Application was still operating and I have SQL data to prove that Time gaps appear in log file, not across two # headers appear at gap Load balancer pings every 30 seconds No caching Here's info on a particular case: an entry appears for 2009-09-21 18:09:27 then #headers the next entry is for 2009-09-22 01:21:54, and so are the next 1600 entries in this log file and 370 in the next log file. about half of the ~2000 entries on 2009-09-22 01:21:54 are load balancer pings (est. at 2/min for 6.9hrs = 828 pings) then entries are recorded as normal. I believe that these events may coincide with me deploying an ASP.NET application update into those machines. Here's some relevant content from the logs in question: ex090921.log line 3684 2009-09-21 17:54:40 GET /ping.aspx - 80 404 0 0 3733 122 0 2009-09-21 17:55:11 GET /ping.aspx - 80 404 0 0 3733 122 0 2009-09-21 17:55:42 GET /ping.aspx - 80 404 0 0 3733 122 0 2009-09-21 17:56:13 GET /ping.aspx - 80 404 0 0 3733 122 0 2009-09-21 17:56:45 GET /ping.aspx - 80 404 0 0 3733 122 0 #Software: Microsoft Internet Information Services 6.0 #Version: 1.0 #Date: 2009-09-21 18:04:37 #Fields: date time cs-method cs-uri-stem cs-uri-query s-port sc-status sc-substatus sc-win32-status sc-bytes cs-bytes time-taken 2009-09-22 01:04:06 GET /ping.aspx - 80 404 0 0 3733 122 3078 2009-09-22 01:04:06 GET /ping.aspx - 80 404 0 0 3733 122 109 2009-09-22 01:04:06 GET /ping.aspx - 80 200 0 0 278 122 3828 2009-09-22 01:04:06 GET /ping.aspx - 80 200 0 0 278 122 0 2009-09-22 01:04:06 GET /ping.aspx - 80 200 0 0 278 122 0 ... continues until line 5449 2009-09-22 01:04:06 GET /ping.aspx - 80 200 0 0 277 122 0 <eof> ex090922.log #Software: Microsoft Internet Information Services 6.0 #Version: 1.0 #Date: 2009-09-22 00:00:16 #Fields: date time cs-method cs-uri-stem cs-uri-query s-port sc-status sc-substatus sc-win32-status sc-bytes cs-bytes time-taken 2009-09-22 01:04:06 GET /ping.aspx - 80 200 0 0 277 122 0 2009-09-22 01:04:06 GET /ping.aspx - 80 200 0 0 277 122 0 ... continues until line 367 2009-09-22 01:04:06 GET /ping.aspx - 80 200 0 0 277 122 0 2009-09-22 01:04:30 GET /ping.aspx - 80 200 0 0 277 122 0 ... back to normal behavior Note the seemingly correct date/time written to the #header of the new log file. Also note that /ping.aspx returned 404 then switched to 200 just as the problem started. I rename the "I'm alive page" so the load balancer stops sending requests to the server while I'm working on it. What you see here is me renaming it back so the load balancer will use the server. So, this problem definitely coincides with me re-enabling the server. Any ideas?

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  • Apache mod_proxy dynamic filter

    - by jrhicks
    How can I configure Apache to ProxyBlock content based on something dynamic such as time-of-day or max-use. Basicly I'm curious about the scriptability of Apache. My web-stumbling leads me to believe I can combine mod-proxy and mod-perl in interesting ways to do dynamic filtering. But I'm pretty lost. What are some general instructions, tutorials, books, technologies to begin scripting Apache (or any suitable proxy).

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  • Help! cant login to my forum after .htaccess changes

    - by MrRioku
    I'm running a phpbb forum and I installed an SEO friendly URL Mod. After I installed it I wasn't able to login as the admin nor any other users... Well I've been messing around with this problem for a bit and I did find out that it was the .htaccess file that was causing me not to be able to login. I found out if I comment the canonical part out in the .htaccess file, my website allows me to login and see the working mod just fine but I get "http://phone7forum.com/" instead of what I want which is "http://www.phone7forum.com/ : enter code here # HERE IS A GOOD PLACE TO FORCE CANONICAL DOMAIN # RewriteCond %{HTTP_HOST} !^www\.phone7forum\.com$ [NC] # RewriteRule ^(.*)$ http://www.phone7forum.com/$1 [QSA,L,R=301] enter code here I definitely want the "http://www." since its the best method and holds the best weight.. But when I un-comment it, it will not allow me to login as the admin nor any user... Is there anything I can do to fix this matter??? I'd like to add, before I found this website I installed the Mod "Canonical URL" found here: http://www.phpbb.com/customise/db/mod/canonical_url/ Possibly this might be part of my issue? Maybe I should go undo everything that Mod told me to do and then try un-commenting the canonical section in the .htaccess file? Here is my complete .htaccess file as of now that produces the "http://phone7forum.com/" and allows me to login: [code] # Lines That should already be in your .htacess <Files "config.php"> Order Allow,Deny Deny from All </Files> <Files "common.php"> Order Allow,Deny Deny from All </Files> # You may need to un-comment the following lines # Options +FollowSymlinks # To make sure that rewritten dir or file (/|.html) will not load dir.php in case it exist # Options -MultiViews # REMEBER YOU ONLY NEED TO STARD MOD REWRITE ONCE RewriteEngine On # Uncomment the statement below if you want to make use of # HTTP authentication and it does not already work. # This could be required if you are for example using PHP via Apache CGI. # RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization},L] # REWRITE BASE RewriteBase / # HERE IS A GOOD PLACE TO FORCE CANONICAL DOMAIN # RewriteCond %{HTTP_HOST} !^www\.phone7forum\.com$ [NC] # RewriteRule ^(.*)$ http://www.phone7forum.com/$1 [QSA,L,R=301] # DO NOT GO FURTHER IF THE REQUESTED FILE / DIR DOES EXISTS RewriteCond %{REQUEST_FILENAME} -f RewriteCond %{REQUEST_FILENAME} -d RewriteRule . - [L] ##################################################### # PHPBB SEO REWRITE RULES ALL MODES ##################################################### # AUTHOR : dcz www.phpbb-seo.com # STARTED : 01/2006 ################################# # FORUMS PAGES ############### # FORUM INDEX REWRITERULE WOULD STAND HERE IF USED. "forum" REQUIRES TO BE SET AS FORUM INDEX # RewriteRule ^forum\.html$ index.php [QSA,L,NC] # FORUM ALL MODES RewriteRule ^(forum|[a-z0-9_-]*-f)([0-9]+)/?(page([0-9]+)\.html)?$ viewforum.php?f=$2&start=$4 [QSA,L,NC] # TOPIC WITH VIRTUAL FOLDER ALL MODES RewriteRule ^(forum|[a-z0-9_-]*-f)([0-9]+)/(topic|[a-z0-9_-]*-t)([0-9]+)(-([0-9]+))?\.html$ viewtopic.php?f=$2&t=$4&start=$6 [QSA,L,NC] # TOPIC WITHOUT FORUM ID & DELIM ALL MODES RewriteRule ^([a-z0-9_-]*)/?(topic|[a-z0-9_-]*-t)([0-9]+)(-([0-9]+))?\.html$ viewtopic.php?forum_uri=$1&t=$3&start=$5 [QSA,L,NC] # PHPBB FILES ALL MODES RewriteRule ^resources/[a-z0-9_-]+/(thumb/)?([0-9]+)$ download/file.php?id=$2&t=$1 [QSA,L,NC] # PROFILES ALL MODES WITH ID RewriteRule ^(member|[a-z0-9_-]*-u)([0-9]+)\.html$ memberlist.php?mode=viewprofile&u=$2 [QSA,L,NC] # USER MESSAGES ALL MODES WITH ID RewriteRule ^(member|[a-z0-9_-]*-u)([0-9]+)-(topics|posts)(-([0-9]+))?\.html$ search.php?author_id=$2&sr=$3&start=$5 [QSA,L,NC] # GROUPS ALL MODES RewriteRule ^(group|[a-z0-9_-]*-g)([0-9]+)(-([0-9]+))?\.html$ memberlist.php?mode=group&g=$2&start=$4 [QSA,L,NC] # POST RewriteRule ^post([0-9]+)\.html$ viewtopic.php?p=$1 [QSA,L,NC] # ACTIVE TOPICS RewriteRule ^active-topics(-([0-9]+))?\.html$ search.php?search_id=active_topics&start=$2&sr=topics [QSA,L,NC] # UNANSWERED TOPICS RewriteRule ^unanswered(-([0-9]+))?\.html$ search.php?search_id=unanswered&start=$2&sr=topics [QSA,L,NC] # NEW POSTS RewriteRule ^newposts(-([0-9]+))?\.html$ search.php?search_id=newposts&start=$2&sr=topics [QSA,L,NC] # UNREAD POSTS RewriteRule ^unreadposts(-([0-9]+))?\.html$ search.php?search_id=unreadposts&start=$2 [QSA,L,NC] # THE TEAM RewriteRule ^the-team\.html$ memberlist.php?mode=leaders [QSA,L,NC] # HERE IS A GOOD PLACE TO ADD OTHER PHPBB RELATED REWRITERULES # FORUM WITHOUT ID & DELIM ALL MODES # THESE THREE LINES MUST BE LOCATED AT THE END OF YOUR HTACCESS TO WORK PROPERLY RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteRule ^([a-z0-9_-]+)/?(page([0-9]+)\.html)?$ viewforum.php?forum_uri=$1&start=$3 [QSA,L,NC] # FIX RELATIVE PATHS : FILES RewriteRule ^.+/(style\.php|ucp\.php|mcp\.php|faq\.php|download/file.php)$ $1 [QSA,L,NC,R=301] # FIX RELATIVE PATHS : IMAGES RewriteRule ^.+/(styles/.*|images/.*)/$ $1 [QSA,L,NC,R=301] # END PHPBB PAGES ##################################################### [/code] Does anyone have any clues as to what I need to do? Any help will be greatly appreciated! Thanks, Justin

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  • Most optimized way to calculate modulus in C

    - by hasanatkazmi
    I have minimize cost of calculating modulus in C. say I have a number x and n is the number which will divide x when n == 65536 (which happens to be 2^16): mod = x % n (11 assembly instructions as produced by GCC) or mod = x & 0xffff which is equal to mod = x & 65535 (4 assembly instructions) so, GCC doesn't optimize it to this extent. In my case n is not x^(int) but is largest prime less than 2^16 which is 65521 as I showed for n == 2^16, bit-wise operations can optimize the computation. What bit-wise operations can I preform when n == 65521 to calculate modulus.

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  • Concatenation with Zero is not occurring properly in code?

    - by Vineet
    I was trying to reverse a number in PL/SQL. It's working fine, but when my number contains any 0, the output is unexpected. For example: 1234 output 4321 1000 output 1 1203 ouput 3021 10001 output 1 DECLARE r number(9); num number(9):=&p_num; BEGIN WHILE num>=1 LOOP IF mod(num,10)=0 THEN -- extracting last digit of a number . r:=r||0; --if end digit is 0 then concat r with 0 ELSE r:=r||mod(num,10);--if mod is not 0 then it would be last digit. END IF; num:=trunc(num/10);--Removing last digit from number END LOOP; dbms_output.put_line(r); END;

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  • Concatenation with Zero is not occuring properly in code?

    - by Vineet
    I was trying to reverse a number in pl/sql ,its working fine but when my number contain any 0,output come unexpected .for eg 1234 output 4321 1000 output 1 1203 ouput 3021 10001 output 1 DECLARE r number(9); num number(9):=&p_num; BEGIN WHILE num>=1 LOOP IF mod(num,10)=0 THEN -- extracting last digit of a number . r:=r||0; --if end digit is 0 then concat r with 0 ELSE r:=r||mod(num,10);--if mod is not 0 then it would be last digit. END IF; num:=trunc(num/10);--Removing last digit from number END LOOP; dbms_output.put_line(r); END;

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  • Help using Horner's rule and Hash Functions in JAVA?

    - by Matt
    I am trying to use Horner's rule to convert words to integers. I understand how it works and how if the word is long, it may cause an overflow. My ultimate goal is to use the converted integer in a hash function h(x)=x mod tableSize. My book suggests, because of the overflow, you could "apply the mod operator after computing each parenthesized expression in Horner's rule." I don't exactly understand what they mean by this. Say the expression looks like this: ((14*32+15)*32+20)*32+5 Do I take the mod tableSize after each parenthesized expression and add them together? What would it look like with this hash function and this example of Horner's rule?

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  • data in mysql show after barcode split and matches character

    - by klox
    i need some code for the next step..this my first step: <script> $("#mod").change(function() { var barcode; barCode=$("#mod").val(); var data=barCode.split(" "); $("#mod").val(data[0]); $("#seri").val(data[1]); var str=data[0]; var matches=str.matches(/EE|[EJU]).*(D)/i); }); </script> after matches..i want the result can connect to data base then show data from table inside <div id="value">...how to do that?

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  • Rendering a variable with erb.

    - by TZer0
    I've got the following problem: I have rhtml (html minced together with ruby inside <% % and <%= % tags) stored in a database which I want to render. The information is acquired through a query. I need to be able to evaluate the information I get from the database as though as it was normal content inside the .erb-file. What I currently have: <% @mymods.each do |mod| %> <%= render_text(mod["html"])%> <% end %> Where mod["html"] is the variable containing the rhtml-code and @mymods an array of objects from the query. I have currently no idea what function I should use (render_text does, of course, not work). Help is greatly appreciated. /TZer0

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  • [Django] Change state of obiects

    - by gameboy
    hi I have following problem. I have model: class Towar(models.Model): nrSeryjny=models.CharField(max_length=100) opis=models.CharField(max_length=255) naStanie=models.NullBooleanField(null=True) def __unicode__(self): return "%s" % self.opis def lowerName(self): return self.__class__.__name__.lower() def checkState(self): return self.naStanie def changeState(self,state): self.naStanie=state class Meta: ordering=['nrSeryjny'] app_label = 'baza' permissions=(("view_towar","mozna miec podglad dla towar"),) and model : class Wypozyczenie(models.Model): dataPobrania=models.DateField() pracownik=models.ForeignKey(User,null=True) kontrahent=models.ForeignKey(Kontrahenci,null=True) towar=models.ForeignKey(Towar,null=True) objects=WypozyczenieManager() default_objects=models.Manager() ZwrotyObjects=WypozyczenieZwrotyManager() def lowerName(self): return self.__class__.__name__.lower() def __unicode__(self): if self.towar == None: return "Dla:%s -- Kto:%s -- Kiedy:%s -- Co:%s" % (self.kontrahent,self.pracownik,self.dataPobrania,"Brak") else: return "Dla:%s -- Kto:%s -- Kiedy:%s -- Co:%s" % (self.kontrahent,self.pracownik,self.dataPobrania,self.towar) class Meta: ordering=['dataPobrania'] app_label = 'baza' permissions=(("view_wypozyczenie","mozna miec podglad dla wypozyczenie"),) and view to adding models: def modelAdd(request,model,modelForm): mod=model() if request.user.has_perm('baza.add_%s' % mod.lowerName()): if request.method=='POST': form=modelForm(request.POST) if form.is_valid(): form.save() return HttpResponseRedirect('/'+ mod.lowerName() + '/') else: form=modelForm() v=RequestContext(request,{'form':form}) return render_to_response('add_form.html',v) and i whant do that, when i add Wypozyczenie and save it then the Towar that is stored by Wypozyczenie change his na stanie from True to False Greets

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