Search Results

Search found 3409 results on 137 pages for 'distributed computing'.

Page 21/137 | < Previous Page | 17 18 19 20 21 22 23 24 25 26 27 28  | Next Page >

  • Hosting and scaling of a facebook application on cloud?

    - by DhruvPathak
    We would be building a facebook application in django(Python), but still not sure of where to host it economically,and with a good provision to scale in case the app gets viral. Some details about the app: i) Would be HTML based like a website,using django as a framework. ii) 100K is the number of expected pageviews in a day,if the app is viral. iii) The users will not generate any media content,only some database data will be generated by them. It would be great if someone with more experience can guide on following points: A) Hosting on google app engine or Amazon EC2 or some other cloud like RackSpace : Preferable points found in AppEngine were ease of deployment,cost effectiveness and easy scaling. For EC2: Full hold of the virtual machine,Amazon NoSQL and RDMBS database services in case we decide to use them. B) Does backend technology affect monthly cost ? eg. would CPU and memory usage difference of Django over , for example , PHP framework like CodeIgnitor really make remarkable difference in running costs. ( Here is the article that triggered this thought process : http://journal.dedasys.com/2010/01/12/rough-estimates-of-the-dollar-cost-of-scaling-web-platforms-part-i#comments) C) Does something like Heroku , which provides additional services over Amazon EC2, prove to be better than raw cloud management ? It is not that we are trying for premature scaling, we just want to have a good start so that we are ready to handle unpredicted growth and scale.

    Read the article

  • Any frameworks or library allow me to run large amount of concurrent jobs schedully?

    - by Yoga
    Are there any high level programming frameworks that allow me to run large amount of concurrent jobs schedully? e.g. I have 100K of urls need to check their uptime every 5 minutes Definitely I can write a program to handle this, but then I need to handle concurrency, queuing, error handling, system throttling, job distribution etc. Will there be a framework that I only focus on a particular job (i.e. the ping task) and the system will take care of the scaling and error handling for me? I am open to any language.

    Read the article

  • Hosting and scaling a Facebook application in the cloud? [migrated]

    - by DhruvPathak
    We would be building a Facebook application in Django (Python), but still not sure of where to host it economically, and with a good provision to scale in case the app gets viral. Some details about the app: Would be HTML based like a website,using django as a framework. 100K is the number of expected pageviews in a day, if the app is viral. The users will not generate any media content, only some database data will be generated by them. It would be great if someone with more experience can guide on following points: A) Hosting on Google app engine or Amazon EC2 or some other cloud like RackSpace : Preferable points found in AppEngine were ease of deployment, cost effectiveness and easy scaling. For EC2: Full hold of the virtual machine,Amazon NoSQL and RDMBS database services in case we decide to use them. B) Does backend technology affect monthly cost? eg. would CPU and memory usage difference of Django over , for example , PHP framework like CodeIgnitor really make remarkable difference in running costs. (Here is the article that triggered this thought process : http://journal.dedasys.com/2010/01/12/rough-estimates-of-the-dollar-cost-of-scaling-web-platforms-part-i#comments) C) Does something like Heroku , which provides additional services over Amazon EC2, prove to be better than raw cloud management? It is not that we are trying for premature scaling, we just want to have a good start so that we are ready to handle unpredicted growth and scale.

    Read the article

  • Combine auto-syncing cloud and VCS

    - by ComFreek
    This question brought me to another question: is there any VCS/tool for a VCS which automatically backups your source code between the last checkout and current changes? I had the problem of loosing uncommited source code changes just one week ago. I did not want to commit yet because the changes were incomplete. But then, an error when moving the data to an USB stick caused the data loss. That's the opposite what a cloud service (like Google Drive, SkyDrive, DropBox, ...) does: it tracks each change you made! Have you lost your data? That's no problem because you have the latest version online. So what would a combined solution look like? It would offer full functionality of a VCS including auto-syncing of any intermediate changes between two commits/checkouts to a temporary online location.

    Read the article

  • Efficient algorithm for Virtual Machine(VM) Consolidation in Cloud

    - by devansh dalal
    PROBLEM: We have N physical machines(PMs) each with ram Ri, cpu Ci and a set of currently scheduled VMs each with ram requirement ri and ci respectively Moving(Migrating) any VM from one PM to other has a cost associated which depends on its ram ri. A PM with no VMs is shut down to save power. Our target is to minimize the weighted sum of (N,migration cost) by migrating some VMs i.e. minimize the number of working PMs as well as not to degrade the service level due to excessive migrations. My Approach: Brute Force approach is choosing the minimum loaded PM and try to fit its VMs to other PMs by First Fit Decreasing algorithm or we can select the victim PMs and target PMs based on their loading level and shut down victims if possible by moving their VMs to targets. I tried this Greedy approach on the Data of Baadal(IIT-D cloud) but It isn't giving promising results. I have also tried to study the Ant colony optimization for dynamic VM consolidating but was unable to understand very much. I used the links. http://dumas.ccsd.cnrs.fr/docs/00/72/52/15/PDF/Esnault.pdf http://hal.archives-ouvertes.fr/docs/00/72/38/56/PDF/RR-8032.pdf Would anyone please clarify the solution or suggest any new approach/resources for better performance. I am basically searching for the algorithms not the physical optimizations and I also know that many commercial organizations have provided these solution but I just wanted to know more the underlying algorithms. Thanks in advance.

    Read the article

  • Do you I think I should integrate something like AWS or other cloud service from the initial phases of my project?

    - by Kareem Ergawy
    Do you I think I should integrate something like AWS or other cloud service from the initial phases of my project or I should be working on the front and back end components regularly and integrate AWS later? I am starting to work on a mobile service. From day one, I wish to make sure that my service will be scalable and able to handle large loads of requests. This is my first time in architecting a large scale system from the beginning so I can't decide what is best.

    Read the article

  • Storing Projects on Google Drive (Cloud)

    - by JamesKraw
    I've started using Google Drive for my cloud needs and backing up pretty much everything. I've got the app installed so it auto-sync's all my content in most things. My question is this, I am currently coding for iOS (although this applies to any coding project) and am split on storing my project files on Google Drive while using sync. My theory is that if I did use it, I'd never have to worry about system crashes or lost code before backups, but if I do use it it will be sync'ing a-lot and I thought there might be problems with it detecting changes and trying to sync for example half way through compiling. Bandwidth isn't an issue as I have fast connection and unlimited monthly allowance. Has anyone ever used this, or similar cloud-based sync'ing (dropbox etc) for this and knows whether it works or not or whether there are any potential problems etc.

    Read the article

  • Running Hadoop example in psuedo-distributed mode on vm

    - by manas
    I have set-up Hadoop on a OpenSuse 11.2 VM using Virtualbox.I have made the prerequisite configs. I ran this example in the Standalone mode successfully. But in psuedo-distributed mode I get the following error: $./bin/hadoop fs -put conf input 10/04/13 15:56:25 INFO hdfs.DFSClient: Exception in createBlockOutputStream java.net.SocketException: Protocol not available 10/04/13 15:56:25 INFO hdfs.DFSClient: Abandoning block blk_-8490915989783733314_1003 10/04/13 15:56:31 INFO hdfs.DFSClient: Exception in createBlockOutputStream java.net.SocketException: Protocol not available 10/04/13 15:56:31 INFO hdfs.DFSClient: Abandoning block blk_-1740343312313498323_1003 10/04/13 15:56:37 INFO hdfs.DFSClient: Exception in createBlockOutputStream java.net.SocketException: Protocol not available 10/04/13 15:56:37 INFO hdfs.DFSClient: Abandoning block blk_-3566235190507929459_1003 10/04/13 15:56:43 INFO hdfs.DFSClient: Exception in createBlockOutputStream java.net.SocketException: Protocol not available 10/04/13 15:56:43 INFO hdfs.DFSClient: Abandoning block blk_-1746222418910980888_1003 10/04/13 15:56:49 WARN hdfs.DFSClient: DataStreamer Exception: java.io.IOException: Unable to create new block. at org.apache.hadoop.hdfs.DFSClient$DFSOutputStream.nextBlockOutputStream(DFSClient.java:2845) at org.apache.hadoop.hdfs.DFSClient$DFSOutputStream.access$2000(DFSClient.java:2102) at org.apache.hadoop.hdfs.DFSClient$DFSOutputStream$DataStreamer.run(DFSClient.java:2288) 10/04/13 15:56:49 WARN hdfs.DFSClient: Error Recovery for block blk_-1746222418910980888_1003 bad datanode[0] nodes == null 10/04/13 15:56:49 WARN hdfs.DFSClient: Could not get block locations. Source file "/user/max/input/core-site.xml" - Aborting... put: Protocol not available 10/04/13 15:56:49 ERROR hdfs.DFSClient: Exception closing file /user/max/input/core-site.xml : java.net.SocketException: Protocol not available java.net.SocketException: Protocol not available at sun.nio.ch.Net.getIntOption0(Native Method) at sun.nio.ch.Net.getIntOption(Net.java:178) at sun.nio.ch.SocketChannelImpl$1.getInt(SocketChannelImpl.java:419) at sun.nio.ch.SocketOptsImpl.getInt(SocketOptsImpl.java:60) at sun.nio.ch.SocketOptsImpl.sendBufferSize(SocketOptsImpl.java:156) at sun.nio.ch.SocketOptsImpl$IP$TCP.sendBufferSize(SocketOptsImpl.java:286) at sun.nio.ch.OptionAdaptor.getSendBufferSize(OptionAdaptor.java:129) at sun.nio.ch.SocketAdaptor.getSendBufferSize(SocketAdaptor.java:328) at org.apache.hadoop.hdfs.DFSClient$DFSOutputStream.createBlockOutputStream(DFSClient.java:2873) at org.apache.hadoop.hdfs.DFSClient$DFSOutputStream.nextBlockOutputStream(DFSClient.java:2826) at org.apache.hadoop.hdfs.DFSClient$DFSOutputStream.access$2000(DFSClient.java:2102) at org.apache.hadoop.hdfs.DFSClient$DFSOutputStream$DataStreamer.run(DFSClient.java:2288) Any leads will be highly appreciated.

    Read the article

  • Computing complex math equations in python

    - by dassouki
    Are there any libraries or techniques that simplify computing equations ? Take the following two examples: F = B * { [ a * b * sumOf (A / B ''' for all i ''' ) ] / [ sumOf(c * d * j) ] } where: F = cost from i to j B, a, b, c, d, j are all vectors in the format [ [zone_i, zone_j, cost_of_i_to_j], [..]] This should produce a vector F [ [1,2, F_1_2], ..., [i,j, F_i_j] ] T_ij = [ P_i * A_i * F_i_j] / [ SumOf [ Aj * F_i_j ] // j = 1 to j = n ] where: n is the number of zones T = vector [ [1, 2, A_1_2, P_1_2], ..., [i, j, A_i_j, P_i_j] ] F = vector [1, 2, F_1_2], ..., [i, j, F_i_j] so P_i would be the sum of all P_i_j for all j and Aj would be sum of all P_j for all i I'm not sure what I'm looking for, but perhaps a parser for these equations or methods to deal with multiple multiplications and products between vectors? To calculate some of the factors, for example A_j, this is what i use from collections import defaultdict A_j_dict = defaultdict(float) for A_item in TG: A_j_dict[A_item[1]] += A_item[3] Although this works fine, I really feel that it is a brute force / hacking method and unmaintainable in the case we want to add more variables or parameters. Are there any math equation parsers you'd recommend? Side Note: These equations are used to model travel. Currently I use excel to solve a lot of these equations; and I find that process to be daunting. I'd rather move to python where it pulls the data directly from our database (postgres) and outputs the results into the database. All that is figured out. I'm just struggling with evaluating the equations themselves. Thanks :)

    Read the article

  • Generating lognormally distributed random number from mean, coeff of variation

    - by Richie Cotton
    Most functions for generating lognormally distributed random numbers take the mean and standard deviation of the associated normal distribution as parameters. My problem is that I only know the mean and the coefficient of variation of the lognormal distribution. It is reasonably straight forward to derive the parameters I need for the standard functions from what I have: If mu and sigma are the mean and standard deviation of the associated normal distribution, we know that coeffOfVar^2 = variance / mean^2 = (exp(sigma^2) - 1) * exp(2*mu + sigma^2) / exp(mu + sigma^2/2)^2 = exp(sigma^2) - 1 We can rearrange this to sigma = sqrt(log(coeffOfVar^2 + 1)) We also know that mean = exp(mu + sigma^2/2) This rearranges to mu = log(mean) - sigma^2/2 Here's my R implementation rlnorm0 <- function(mean, coeffOfVar, n = 1e6) { sigma <- sqrt(log(coeffOfVar^2 + 1)) mu <- log(mean) - sigma^2 / 2 rlnorm(n, mu, sigma) } It works okay for small coefficients of variation r1 <- rlnorm0(2, 0.5) mean(r1) # 2.000095 sd(r1) / mean(r1) # 0.4998437 But not for larger values r2 <- rlnorm0(2, 50) mean(r2) # 2.048509 sd(r2) / mean(r2) # 68.55871 To check that it wasn't an R-specific issue, I reimplemented it in MATLAB. (Uses stats toolbox.) function y = lognrnd0(mean, coeffOfVar, sizeOut) if nargin < 3 || isempty(sizeOut) sizeOut = [1e6 1]; end sigma = sqrt(log(coeffOfVar.^2 + 1)); mu = log(mean) - sigma.^2 ./ 2; y = lognrnd(mu, sigma, sizeOut); end r1 = lognrnd0(2, 0.5); mean(r1) % 2.0013 std(r1) ./ mean(r1) % 0.5008 r2 = lognrnd0(2, 50); mean(r2) % 1.9611 std(r2) ./ mean(r2) % 22.61 Same problem. The question is, why is this happening? Is it just that the standard deviation is not robust when the variation is that wide? Or have a screwed up somewhere?

    Read the article

  • Apache's AuthDigestDomain and Rails Distributed Asset Hosts

    - by Jared
    I've got a server I'm in the process of setting up and I'm running into an Apache configuration problem that I can not get around. I've got Apache 2.2 and Passenger serving a Rails app with distributed asset hosting. This is the feature of Rails that lets you serve your static assets from assets0.example.com, assets1, assets2, and so on. The site needs to be passworded until launch. I've set up HTTP authentication on the site using Apache's mod_auth_digest. In my configuration I'm attempting to use the AuthDigestDomain directive to allow access to each of the asset URLs. The problem is, it doesn't seem to be working. I get the initial prompt for the password when I load the page, but then the first time it loads an asset from one of the asset URLs, I get prompted a 2nd, 3rd, or 4th time. In some browsers, I get prompted for every single resource on the page. I'm hoping that this is only a problem of how I'm specifying my directives and not a limitation of authorization in Apache itself. See the edited auth section below: <Location /> AuthType Digest AuthName "Restricted Site" AuthUserFile /etc/httpd/passwd/passwords AuthGroupFile /dev/null AuthDigestDomain / http://assets0.example.com/ http://assets1.example.com/ http://assets2.example.com/ http://assets3.example.com/ require valid-user order deny,allow allow from all </Location>

    Read the article

  • Building a new cluster for mathematical calculations (Win/Lin)

    - by Muhammad Farhan
    I would like to build a new cluster to perform heavy mathematical calculations in Matlab and Abaqus. One of my friend told me that distributed computing is way faster than parallel computing, which is very true after reading a bit on the internet. However, I have never clustered before. Current workstation I own: Dell Precision T5400 2 x Intel Xeon 2.5 GHz 16 GB RAM (2GB x 8) 1 x Western Digital 1TB HDD 7200 rpm 1 x nVidia Quadro FX4600 768MB GPU 1 x 870W PSU OS: Windows 7 Ultimate 64-bit 2nd WS: I can buy another WS similar configuration to the one I own I am not bothered about OS, I am willing to cluster with either Windows or Linux. However, my software are compatible with windows 64-bit only. Please help me setup a cluster. Thank you.

    Read the article

  • Is there any way to distribute x264 encoding jobs across multiple computers (to increase the encodin

    - by Breakthrough
    Does anyone know of a current, active solution to encoding x264 videos across many computers (via the network) to increase encoding FPS? I heard in the past of the project x264farm; unfortunately, it is not actively developed anymore, and isn't compatible with newer x264 builds. I'm looking for a current solution, which is compatible with newer builds of x264. Just to note this, I'm a Windows user, so I'm only looking for Windows solutions (or at the very least, Linux). I've also seen the ELDER distributed encoder, but the quality varies depending on the settings you use - I'd prefer a solution similar to x264farm as noted above (the documentation outlines the encoding process), but one that is compatible with new(er) x264 builds, and is preferably actively developed. Final Edit: Unfortunately, the bounty for this question has expired, and I haven't found a decent solution for this. So if at any time someone finds a new, distributed encoding solution for x264 (or any h.264 coded, for that matter) - please answer this question! I'd love to discover an ideal method to make this work!

    Read the article

  • NTRU Pseudo-code for computing Polynomial Inverses

    - by Neville
    Hello all. I was wondering if anyone could tell me how to implement line 45 of the following pseudo-code. Require: the polynomial to invert a(x), N, and q. 1: k = 0 2: b = 1 3: c = 0 4: f = a 5: g = 0 {Steps 5-7 set g(x) = x^N - 1.} 6: g[0] = -1 7: g[N] = 1 8: loop 9: while f[0] = 0 do 10: for i = 1 to N do 11: f[i - 1] = f[i] {f(x) = f(x)/x} 12: c[N + 1 - i] = c[N - i] {c(x) = c(x) * x} 13: end for 14: f[N] = 0 15: c[0] = 0 16: k = k + 1 17: end while 18: if deg(f) = 0 then 19: goto Step 32 20: end if 21: if deg(f) < deg(g) then 22: temp = f {Exchange f and g} 23: f = g 24: g = temp 25: temp = b {Exchange b and c} 26: b = c 27: c = temp 28: end if 29: f = f XOR g 30: b = b XOR c 31: end loop 32: j = 0 33: k = k mod N 34: for i = N - 1 downto 0 do 35: j = i - k 36: if j < 0 then 37: j = j + N 38: end if 39: Fq[j] = b[i] 40: end for 41: v = 2 42: while v < q do 43: v = v * 2 44: StarMultiply(a; Fq; temp;N; v) 45: temp = 2 - temp mod v 46: StarMultiply(Fq; temp; Fq;N; v) 47: end while 48: for i = N - 1 downto 0 do 49: if Fq[i] < 0 then 50: Fq[i] = Fq[i] + q 51: end if 52: end for 53: {Inverse Poly Fq returns the inverse polynomial, Fq, through the argument list.} The function StarMultiply returns a polynomial (array) stored in the variable temp. Basically temp is a polynomial (I'm representing it as an array) and v is an integer (say 4 or 8), so what exactly does temp = 2-temp mod v equate to in normal language? How should i implement that line in my code. Can someone give me an example. The above algorithm is for computing Inverse polynomials for NTRUEncrypt key generation. The pseudo-code can be found on page 28 of this document. Thanks in advance.

    Read the article

  • SAP se lance dans le Cloud Computing et présente la première application de sa nouvelle gamme « On-Demand »

    SAP se lance dans le Cloud Computing Et présente la première application de sa nouvelle génération d'applications « On-Demand » Cette année, la participation de SAP au très prestigieux salon CeBIT s'articule autour de la promotion de la nouvelle génération de ses solutions « On-Demand », alliant la puissance du Cloud Computing à la flexibilité du paiement à l'utilisation en mode SaaS. Pour répondre aux attentes des entreprises qui cherchent aujourd'hui à optimiser leurs processus business et les adapter à leurs métiers sans réinvestir dans leurs systèmes d'informations, SAP introduit une nouvelle gamme de solutions On-Demand, intégrée à la suite logicielle SAP Business Suite.

    Read the article

  • Ouverture de la rubrique Cloud Computing, pour trouver les ressources nécessaires à la compréhension et à l'utilisation du "Cloud"

    Bonjour à tous, La rubrique Cloud Computing vient de voir le jour à l'adresse http://cloud-computing.developpez.com. Cette rubrique contiendra des news et toutes les ressources nécessaires à la compréhension, à l'utilisation et au développement pour et avec le "Cloud". Si vous avez des idées de tutoriels, d'articles, de sources ou encore de Q/R pour de prochaines FAQ, n'hésitez pas à nous en faire part. Très cordialement, Gordon...

    Read the article

  • Ouverture de la rubrique Cloud Computing, pour trouver les ressources nécessaires à la compréhension et à l'utilisation du "Cloud"

    Bonjour à tous, La rubrique Cloud Computing vient de voir le jour à l'adresse http://cloud-computing.developpez.com. Cette rubrique contiendra des news et toutes les ressources nécessaires à la compréhension, à l'utilisation et au développement pour et avec le "Cloud" (de Windows Azure aux Google Apps en passant par Salesforce et les serveurs HPC). Si vous avez des idées de tutoriels, d'articles, de sources ou encore de Q/R pour de prochaines FAQ, n'hésitez pas à nous en faire part. Très cordialement, Gordon...

    Read the article

  • Running Awk command on a cluster

    - by alex
    How do you execute a Unix shell command (awk script, a pipe etc) on a cluster in parallel (step 1) and collect the results back to a central node (step 2) Hadoop seems to be a huge overkill with its 600k LOC and its performance is terrible (takes minutes just to initialize the job) i don't need shared memory, or - something like MPI/openMP as i dont need to synchronize or share anything, don't need a distributed VM or anything as complex Google's SawZall seems to work only with Google proprietary MapReduce API some distributed shell packages i found failed to compile, but there must be a simple way to run a data-centric batch job on a cluster, something as close as possible to native OS, may be using unix RPC calls i liked rsync simplicity but it seem to update remote notes sequentially, and you cant use it for executing scripts as afar as i know switching to Plan 9 or some other network oriented OS looks like another overkill i'm looking for a simple, distributed way to run awk scripts or similar - as close as possible to data with a minimal initialization overhead, in a nothing-shared, nothing-synchronized fashion Thanks Alex

    Read the article

  • What are the memory-management capabilities of MySQL + JDBC (in light of autonomic computing)?

    - by Adel
    I'm interested in implementing some kind of autonomic-computing functionality using MySQL. By autonomic-computing I mean roughly some failsafe abilities, whereby the application appears to be at least slightly "intelligent" For reference, the main parts of autonomic computing we'd like are the "self-configuring" and "self-healing" features (the other two - "self-optimizing" and "self-protecting", are too abstract/futuristic for us, at this time). Sofor example, if we have a sample Java application that utilizes a MySQL database, we might want to automatically restart the MySQL database if we take up too much memory. Or maybe we want to have the ability to dynamiccally adjust the database memory as needed. So for example, when we start the application the database begins with a 56 Megabyte buffer; but then as we insert so many rows we want to have it automatically jump up to 512 MB, then to 1024, until a max of 4096 MB. Does all of the above suggest that MySQL is too "weak" for the task? Do you suggest using Oracle database? My professor believes that by using Java we can basically make up for any memory-management deficiencies that MySQL has in relation to Oracle DB. I'm new to MySQL , but have experience with Oracle. If all of the above sounds wishy-washy, it is because I'm still fleshing it out. thanks

    Read the article

  • Computing MD5SUM of large files in C#

    - by spkhaira
    I am using following code to compute MD5SUM of a file - byte[] b = System.IO.File.ReadAllBytes(file); string sum = BitConverter.ToString(new MD5CryptoServiceProvider().ComputeHash(b)); This works fine normally, but if I encounter a large file (~1GB) - e.g. an iso image or a DVD VOB file - I get an Out of Memory exception. Though, I am able to compute the MD5SUM in cygwin for the same file in about 10secs. Please suggest how can I get this to work for big files in my program. Thanks

    Read the article

  • computing "node closure" of graph with removal

    - by Fakrudeen
    Given a directed graph, the goal is to combine the node with the nodes it is pointing to and come up with minimum number of these [lets give the name] super nodes. The catch is once you combine the nodes you can't use those nodes again. [first node as well as all the combined nodes - that is all the members of one super node] The greedy approach would be to pick the node with maximum out degree and combine that node with nodes it is pointing to and remove all of them. Do this every time with the nodes which are not removed yet from graph. The greedy is O(V), but this won't necessarily output minimum number super nodes. So what is the best algorithm to do this?

    Read the article

  • Computing orientation of a square and displaying an object with the same orientation

    - by Robin
    Hi, I wrote an application which detects a square within an image. To give you a good understanding of how such an image containing such a square, in this case a marker, could look like: What I get, after the detection, are the coordinates of the four corners of my marker. Now I don't know how to display an object on my marker. The object should have the same rotation/angle/direction as the marker. Are there any papers on how to achieve that, any algorithms that I can use that proofed to be pretty solid/working? It doesn't need to be a working solution, it could be a simple description on how to achieve that or something similar. If you point me at a library or something, it should work under linux, windows is not needed but would be great in case I need to port the application at some point. I already looked at the ARToolkit but they you camera parameter files and more complex matrices while I only got the four corner points and a single image instead of a whole video / camera stream.

    Read the article

  • computing z-scores for 2D matrices in scipy/numpy in Python

    - by user248237
    How can I compute the z-score for matrices in Python? Suppose I have the array: a = array([[ 1, 2, 3], [ 30, 35, 36], [2000, 6000, 8000]]) and I want to compute the z-score for each row. The solution I came up with is: array([zs(item) for item in a]) where zs is in scipy.stats.stats. Is there a better built-in vectorized way to do this? Also, is it always good to z-score numbers before using hierarchical clustering with euclidean or seuclidean distance? Can anyone discuss the relative advantages/disadvantages? thanks.

    Read the article

  • Computing unique index for every poker starting hand

    - by Aly
    As there are 52 cards in a deck we know there are 52 choose 2 = 1326 distinct matchups, however in preflop poker this can be bucketed into 169 different hands such as AK offsuit and AK suited as whether it is A hearts K hearts or A spade K spades it makes no difference preflop. My question is, is there a nice mathematical property in which I can uniquely index each of these 169 hands (from 0 to 168 preferably). I am trying to create a look up table as a double[][] = new double [169][169] but have no way of changing a hand representation such as AKs (an Ace and a King of the same suit) to a unique index in this array.

    Read the article

< Previous Page | 17 18 19 20 21 22 23 24 25 26 27 28  | Next Page >