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  • 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.

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  • Are there any libraries for parsing "number expressions" like 1,2-9,33- in Java

    - by mihi
    Hi, I don't think it is hard, just tedious to write: Some small free (as in beer) library where I can put in a String like 1,2-9,33- and it can tell me whether a given number matches that expression. Just like most programs have in their print range dialogs. Special functions for matching odd or even numbers only, or matching every number that is 2 mod 5 (or something like that) would be nice, but not needed. The only operation I have to perform on this list is whether the range contains a given (nonnegative) integer value; more operations like max/min value (if they exist) or an iterator would be nice, of course. What would be needed that it does not occupy lots of RAM if anyone enters 1-10000000 but the only number I will ever query is 12345 :-) (To implement it, I would parse a list into several (min/max/value/mod) pairs, like 1,10,0,1 for 1-10 or 11,33,1,2 for 1-33odd, or 12,62,2,10 for 12-62/10 (i. e. 12, 22, 32, ..., 62) and then check each number for all the intervals. Open intervals by using Integer.MaxValue etc. If there are no libs, any ideas to do it better/more efficient?)

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  • Context Free Language Question (Pumping Lemma)

    - by Maixy
    I know this isn't directly related to programming, but I was wondering if anyone know how to apply the pumping lemma to the following proof: Show that L={(a^n)(b^n)(c^m) : n!=m} is not a context free language I'm pretty confident with applying pumping lemmas, but this one is really irking me. What do you think?

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  • multi-shop orders table and sequential order numbers based on shop

    - by imanc
    Hey, I am looking at building a shop solution that needs to be scalable. Currently it retrieves 1-2000 orders on average per day across multiple country based shops (e.g. uk, us, de, dk, es etc.) but this order could be 10x this amount in two years. I am looking at either using separate country-shop databases to store the orders tables, or looking to combine all into one order table. If all orders exist in one table with a global ID (auto num) and country ID (e.g uk,de,dk etc.), each countries orders would also need to have sequential ordering. So in essence, we'd have to have a global ID and a country order ID, with the country order ID being sequential for countries only, e.g. global ID = 1000, country = UK, country order ID = 1000 global ID = 1001, country = DE, country order ID = 1000 global ID = 1002, country = DE, country order ID = 1001 global ID = 1003, country = DE, country order ID = 1002 global ID = 1004, country = UK, country order ID = 1001 THe global ID would be DB generated and not something I would need to worry about. But I am thinking that I'd have to do a query to get the current country order based ID+1 to find the next sequential number. Two things concern me about this: 1) query times when the table has potentially millions of rows of data and I'm doing a read before a write, 2) the potential for ID number clashes due to simultaneous writes/reads. With a MyISAM table the entire table could be locked whilst the last country order + 1 is retrieved, to prevent ID number clashes. I am wondering if anyone knows of a more elegant solution? Cheers, imanc

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  • Convert a post-order binary tree traversal index to an level-order (breadth-first) index

    - by strfry
    Assuming a complete binary tree, each node can be adressed with the position it appears in a given tree traversal algorithm. For example, the node indices of a simple complete tree with height 3 would look like this: breadth first (aka level-order): 0 / \ 1 2 / \ / \ 3 4 5 6 post-order dept first: 6 / \ 2 5 / \ / \ 0 1 3 4 The height of the tree and an index in the post-order traversal is given. How can i calculate the breadth first index from this information?

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  • Show a number with specified number of significant digits

    - by dreeves
    I use the following function to convert a number to a string for display purposes (don't use scientific notation, don't use a trailing dot, round as specified): (* Show Number. Convert to string w/ no trailing dot. Round to the nearest r. *) Unprotect[Round]; Round[x_,0] := x; Protect[Round]; shn[x_, r_:0] := StringReplace[ ToString@NumberForm[Round[N@x,r], ExponentFunction->(Null&)], re@"\\.$"->""] (Note that re is an alias for RegularExpression.) That's been serving me well for years. But sometimes I don't want to specify the number of digits to round to, rather I want to specify a number of significant figures. For example, 123.456 should display as 123.5 but 0.00123456 should display as 0.001235. To get really fancy, I might want to specify significant digits both before and after the decimal point. For example, I might want .789 to display as 0.8 but 789.0 to display as 789 rather than 800. Do you have a handy utility function for this sort of thing, or suggestions for generalizing my function above? Related: Suppressing a trailing "." in numerical output from Mathematica

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  • Biased Random Number Generator

    - by cmptrer
    I am looking for a random number generator that can be biased. For instance, say I want a random number between 1-5, with the probability being: 1: Comes up 20% of the time 2: Comes up 10% of the time 3: Comes up 40% of the time 4: Comes up 25% of the time 5: Comes up 5% of the time Is there anything in the standard library, or other libraries out there that would do this? Alternatively, is there an efficient way to do this myself?

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  • How would I create a random number?

    - by Elliot Bonneville
    How would I create a random number using C++? I've heard that one should use the time as a seed, but I'm not sure how to do that with the correct syntax. How would I do this? One more thing - how would I limit the random number to a particular range? I'm simulating a dice roll and getting numbers in the millions...

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  • Extract number from string in MSBuild

    - by Ole Lynge
    I would like to extract the number from a string in MSBuild. How can I do that using the built in tasks or the MSBuild.Community.Tasks? (RegexMatch might do, but how?) Example: I have the string agent0076 and I would like to get out the number, without the leading zeros: 76

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  • Generating exactly prime number with Java

    - by Viet
    Hi, I'm aware of the function BigInteger.probablePrime(int bitLength, Random rnd) that outputs probably prime number of any bit length. I want a REAL prime number in Java. Is there any FOSS library to do so with acceptable performance? Thanks in advance!

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  • Format a number as currency in a JTable?

    - by llm
    Given a JTable where one of the columns contains a number, how do I display this number as a currency? I.e. 5 should display as $5.00 etc. Can this be done directly on the JTable after it has been populated with data, or do I have to do this earlier? Thanks.

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  • Insert lecture number and page number of lecture in footline

    - by Liam
    I am dividing a semester's worth of lectures via the \lecture command. I'd like to have in the footline (among other things) the lecture number, date, and page number of the current lecture. I would also like to use the default style footline, with the black box on the left and the blue on the right. So I define a lecture with e.g. \lecture{January 28, 2010}{lecture01} with \title[Lecture \insertlecturenumber{}(\insertlecture)\quad{}Page \insertframenumber]{Course Title} in the preamble, I get an error; it will not accept \insertlecture there. If I remove \insertlecture, it does what I want, except that the page number is counted from the start of the semester, not the lecture. Is there any way to do this? Thank you. Liam

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  • Rounding a positive number to a power of another number

    - by Sagekilla
    I'm trying to round a number to the next smallest power of another number. The number I'm trying to round is always positive. I'm not particular on which direction it rounds, but I prefer downwards if possible. I would like to be able to round towards arbitrary bases, but the ones I'm most concerned with at the moment is base 2 and fractional powers of 2 like 2^(1/2), 2^(1/4), and so forth. Here's my current algorithm for base 2. The log2 I multiply by is actually the inverse of log2: double roundBaseTwo(double x) { return 1.0 / (1 << (int)((log(x) * log2)) } Any help would be appreciated!

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  • convert javascript number to css value -- maximum number of trailing decimals

    - by philipp
    I am about to have some fun with the css transform matrix and javascript. At the moment everything is cool, except when a number becomes something like 0.000034e3344 after the to string conversion. Than the transform does not work. So I know that there is the Number.toFixed() method which actually solves the problem, but i ask myself how many trailing decimals make sense. So what is the highest value i can pass to the toFixed() method to get the most precise results? EDIT::: the exact number output was: 9.685539407532573e-20

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  • C# Random Number Generator getting stuck in a cycle

    - by Jean Azzopardi
    Hi, I am using .NET to create an artificial life program and I am using C#'s pseudo random class defined in a Singleton. The idea is that if I use the same random number generator throughout the application, I could merely save the seed and then reload from the seed to recompute a certain interesting run. public sealed class RandomNumberGenerator : Random { private static readonly RandomNumberGenerator instance = new RandomNumberGenerator(); RandomNumberGenerator() { } public static RandomNumberGenerator Instance { get { return instance; } } } I also wanted a method that could give me two different random numbers. public static Tuple<int, int> TwoDifferentRandomNumbers(this Random rnd, int minValue, int maxValue) { if (minValue >= maxValue) throw new ArgumentOutOfRangeException("maxValue", "maxValue must be greater than minValue"); if (minValue + 1 == maxValue) return Tuple.Create<int, int>(minValue, maxValue); int rnd1 = rnd.Next(minValue, maxValue); int rnd2 = rnd.Next(minValue, maxValue); while (rnd1 == rnd2) { rnd2 = rnd.Next(minValue, maxValue); } return Tuple.Create<int, int>(rnd1, rnd2); } The problem is that sometimes rnd.Next(minValue,maxValuealways returns minValue. If I breakpoint at this point and try creating a double and setting it to rnd.NextDouble(), it returns 0.0. Anyone know why this is happening? I know that it is a pseudo random number generator, but frankly, I hadn't expected it to lock at 0. The random number generator is being accessed from multiple threads... could this be the source of the problem?

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  • Graph Theory: How to compute closeness centrality for each node in a set of data?

    - by Jordan
    I'd like to learn how to apply network theory to my own cache of relational data. I'm trying to build a demo of a new way of browsing a music library, using network theory, that I think would make for a very intuitive and useful way of finding the right song at any given time. I have all the data (artists as nodes, similarity from 0 to 1 between each artist and those it is related to) and I can already program, but I don't know how to actually calculate the centrality of a node from that. I've spent a while trying to email different professors at my school but no one seems to know where I can learn this. I hope someone's done something similar. Thanks in advance you guys! ~Jordan

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  • How can I make an even more random number in ActionScript 2.0

    - by Theo
    I write a piece of software that runs inside banner ads which generates millions of session IDs every day. For a long time I've known that the random number generator in Flash is't random enough to generate sufficiently unique IDs, so I've employed a number of tricks to get even more random numbers. However, in ActionScript 2.0 it's not easy, and I'm seeing more and more collisions, so I wonder if there is something I've overlooked. As far as I can tell the problem with Math.random() is that it's seeded by the system time, and when you have sufficient numbers of simultaneous attempts you're bound to see collisions. In ActionScript 3.0 I use the System.totalMemory, but there's no equivalent in ActionScript 2.0. AS3 also has Font.enumerateFonts, and a few other things that are different from system to system. On the server side I also add the IP address to the session ID, but even that isn't enough (for example, many large companies use a single proxy server and that means that thousands of people all have the same IP -- and since they tend to look at the same sites, with the same ads, roughly at the same time, there are many session ID collisions). What I need isn't something perfectly random, just something that is random enough to dilute the randomness I get from Math.random(). Think of it this way: there is a certain chance that two people will generate the same random number sequence using only Math.random(), but the chance of two people generating the same sequence and having, say, the exact same list of fonts is significantly lower. I cannot rely on having sufficient script access to use ExternalInterface to get hold of things like the user agent, or the URL of the page. I don't need suggestions of how to do it in AS3, or any other system, only AS2 -- using only what's available in the standard APIs. The best I've come up with so far is to use the list of microphones (Microphone.names), but I've also tried to make some fingerprinting using some of the properties in System.capabilities, I'm not sure how much randomness I can get out of that though so I'm not using that at the moment. I hope I've overlooked something.

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  • Algorithm to calculate the number of divisors of a given number

    - by sker
    What would be the most optimal algorithm (performance-wise) to calculate the number of divisors of a given number? It'll be great if you could provide pseudocode or a link to some example. EDIT: All the answers have been very helpful, thank you. I'm implementing the Sieve of Atkin and then I'm going to use something similar to what Jonathan Leffler indicated. The link posted by Justin Bozonier has further information on what I wanted.

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  • number several equations with only one number

    - by Tim
    Hi, How can I number several equations in a align environment using only one number? For example \begin{align} w^T x_i + b \geqslant 1-\xi_i \text{ if } y_i=1, \nonumber \\ w^T x_i + b \leqslant -1+\xi_i \text{ if } y_i=-1, \end{align} The numbering will appear next to the second equation. But it would be better if it appears between the lines of the two equations. In this case how to label this group of equations for later referring to? Thanks and regards!

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  • Warning: PDOStatement::execute(): SQLSTATE[HY093]: Invalid parameter number: number of bound variabl

    - by Thomas
    Hi, I'm working with PHP PDO and I have the following problem: Warning: PDOStatement::execute(): SQLSTATE[HY093]: Invalid parameter number: number of bound variables does not match number of tokens in /var/www/site/classes/enterprise.php on line 63 Here is my code: public function getCompaniesByCity(City $city, $options = null) { $database = Connection::getConnection(); if(empty($options)) { $statement = $database-prepare("SELECT * FROM empresas WHERE empresas.cidades_codigo = ?"); $statement-bindValue(1, $city-getId()); } else { $sql = "SELECT * FROM empresas INNER JOIN prods_empresas ON prods_empresas.empresas_codigo = empresas.codigo WHERE "; foreach($options as $option) { $sql .= 'prods_empresas.produtos_codigo = ? OR '; } $sql = substr($sql, 0, -4); $sql .= ' AND empresas.cidades_codigo = ?'; $statement = $database-prepare($sql); echo $sql; foreach($options as $i = $option) { $statement-bindValue($i + 1, $option-getId()); } $statement-bindValue(count($options), $city-getId()); } $statement-execute(); $objects = $statement-fetchAll(PDO::FETCH_OBJ); $companies = array(); if(!empty($objects)) { foreach($objects as $object) { $data = array( 'id' = $object-codigo, 'name' = $object-nome, 'link' = $object-link, 'email' = $object-email, 'details' = $object-detalhes, 'logo' = $object-logo ); $enterprise = new Enterprise($data); array_push($companies, $enterprise); } return $companies; } } Thank you very much!

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