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  • How can I access the group of a linq group-by query from a nested repeater control?

    - by Duke
    I'm using a linq group by query (with two grouping parameters) and would like to use the resulting data in a nested repeater. var dateGroups = from row in data.AsEnumerable() group row by new { StartDate = row["StartDate"], EndDate = row["EndDate"] }; "data" is a DataTable from an SqlDataAdapter-filled DataSet. "dateGroups" is used in the parent repeater, and I can access the group keys using Eval("key.StartDate") and Eval("key.EndDate"). Since dateGroups actually contains all the data rows grouped neatly by Start/End date, I'd like to access those rows to display the data in a child repeater. To what would I set the child repeater's DataSource? I have tried every expression in markup I could think of; I think the problem is that I'm trying to access an anonymous member (and I don't know how.) In case it doesn't turn out to be obvious, what would be the expression to access the elements in each iteration of the child repeater? Is there an expression that would let me set the DataSource in the markup, or will it have to be in the codebehind on some event in the parent repeater?

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  • Java how can I add an accented "e" to a string?

    - by behrk2
    Hello, With the help of tucuxi from the existing post Java remove HTML from String without regular expressions I have built a method that will parse out any basic HTML tags from a string. Sometimes, however, the original string contains html hexadecimal characters like é (which is an accented e). I have started to add functionality which will translate these escaped characters into real characters. You're probably asking: Why not use regular expressions? Or a third party library? Unfortunately I cannot, as I am developing on a BlackBerry platform which does not support regular expressions and I have never been able to successfully add a third party library to my project. So, I have gotten to the point where any é is replaced with "e". My question now is, how do I add an actual 'accented e' to a string? Here is my code: public static String removeHTML(String synopsis) { char[] cs = synopsis.toCharArray(); String sb = new String(); boolean tag = false; for (int i = 0; i < cs.length; i++) { switch (cs[i]) { case '<': if (!tag) { tag = true; break; } case '>': if (tag) { tag = false; break; } case '&': char[] copyTo = new char[7]; System.arraycopy(cs, i, copyTo, 0, 7); String result = new String(copyTo); if (result.equals("&#x00E9")) { sb += "e"; } i += 7; break; default: if (!tag) sb += cs[i]; } } return sb.toString(); } Thanks!

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  • Good grammar for date data type for recursive descent parser LL(1)

    - by Totophil
    I'm building a custom expression parser and evaluator for production enviroment to provide a limited DSL to the users. The parser itself as the DSL, need to be simple. The parser is going to be built in an exotic language that doesn't support dynamic expression parsing nor has any parser generator tools available. My decision is to go for recursive descent approach with LL(1) grammar, so that even programmers with no previous experience in evaluating expression could quickly learn how the code works. It has to handle mixed expressions made up of several data types: decimals, percentages, strings and dates. And dates in the format of dd/mm/yyyy are easy to confuse with a string of devision ops. Is where a good solution to this problem? My own solution that is aimed at keeping the parser simple involves prefixing dates with a special symbol, let's say apostrophe: <date> ::= <apostr><digit><digit>/<digit><digit>/<digit><digit><digit><digit> <apostr> ::= ' <digit> ::= '0'..'9'

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  • Why does division yield a vastly different result than multiplication by a fraction in floating points.

    - by Avram
    I understand why floating point numbers can't be compared, and know about the mantissa and exponent binary representation, but I'm no expert and today I came across something I don't get: Namely lets say you have something like: float denominator, numerator, resultone, resulttwo; resultone = numerator / denominator; float buff = 1 / denominator; resulttwo = numerator * buff; To my knowledge different flops can yield different results and this is not unusual. But in some edge cases these two results seem to be vastly different. To be more specific in my GLSL code calculating the Beckmann facet slope distribution for the Cook-Torrance lighitng model: float a = 1 / (facetSlopeRMS * facetSlopeRMS * pow(clampedCosHalfNormal, 4)); float b = clampedCosHalfNormal * clampedCosHalfNormal - 1.0; float c = facetSlopeRMS * facetSlopeRMS * clampedCosHalfNormal * clampedCosHalfNormal; facetSlopeDistribution = a * exp(b/c); yields very very different results to float a = (facetSlopeRMS * facetSlopeRMS * pow(clampedCosHalfNormal, 4)); facetDlopeDistribution = exp(b/c) / a; Why does it? The second form of the expression is problematic. If I say try to add the second form of the expression to a color I get blacks, even though the expression should always evaluate to a positive number. Am I getting an infinity? A NaN? if so why?

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  • C# Regex - Replace multiple characters at once without overwriting?

    - by Everaldo Aguiar
    Hello guys, I'm implementing a c# program that should automatize a Mono-alphabetic substitution cipher. The functionality i'm working on at the moment is the simplest one: The user will provide a plain text and a cipher alphabet, for example: Plain text(input): THIS IS A TEST Cipher alphabet: A - Y, H - Z, I - K, S - L, E - J, T - Q Cipher Text(output): QZKL KL QJLQ I thought of using regular expressions since I've been programming in perl for a while, but I'm encountering some problems on c#. First I would like to know if someone would have a suggestion for a regular expression that would replace all occurrence of each letter by its corresponding cipher letter (provided by user) at once and without overwriting anything. Example: In this case, user provides plaintext "TEST", and on his cipher alphabet, he wishes to have all his T's replaced with E's, E's replaced with Y and S replaced with J. My first thought was to substitute each occurrence of a letter with an individual character and then replace that character by the cipherletter corresponding to the plaintext letter provided. Using the same example word "TEST", the steps taken by the program to provide an answer would be: 1 - replace T's with (lets say) @ 2 - replace E's with # 3 - replace S's with & 4 - Replace @ with E, # with Y, & with j 5 - Output = EYJE This solution doesn't seem to work for large texts. I would like to know if anyone can think of a single regular expression that would allow me to replace each letter in a given text by its corresponding letter in a 26-letter cipher alphabet without the need of splitting the task in an intermediate step as I mentioned. If it helps visualize the process, this is a print screen of my GUI for the program: http://img43.imageshack.us/img43/2118/11618743.jpg

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  • Programming R/Sweave for proper \Sexpr output

    - by deoksu
    Hi I'm having a bit of a problem programming R for Sweave, and the #rstats twitter group often points here, so I thought I'd put this question to the SO crowd. I'm an analyst- not a programmer- so go easy on me my first post. Here's the problem: I am drafting a survey report in Sweave with R and would like to report the marginal returns in line using \Sexpr{}. For example, rather than saying: Only 14% of respondents said 'X'. I want to write the report like this: Only \Sexpr{p.mean(variable)}$\%$ of respondents said 'X'. The problem is that Sweave() converts the results of the expression in \Sexpr{} to a character string, which means that the output from expression in R and the output that appears in my document are different. For example, above I use the function 'p.mean': p.mean<- function (x) {options(digits=1) mmm<-weighted.mean(x, weight=weight, na.rm=T) print(100*mmm) } In R, the output looks like this: p.mean(variable) >14 but when I use \Sexpr{p.mean(variable)}, I get an unrounded character string (in this case: 13.5857142857143) in my document. I have tried to limit the output of my function to 'digits=1' in the global environment, in the function itself, and and in various commands. It only seems to contain what R prints, not the character transformation that is the result of the expression and which eventually prints in the LaTeX file. as.character(p.mean(variable)) >[1] 14 >[1] "13.5857142857143" Does anyone know what I can do to limit the digits printed in the LaTeX file, either by reprogramming the R function or with a setting in Sweave or \Sexpr{}? I'd greatly appreciate any help you can give. Thanks, David

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  • Regex For Finding Ctypes with Int32

    - by Stefan H
    (Hey all, I am looking for a little regex help... I am trying to find all CType(expression,Int32) s and replace them with CInt(expression) This, however, is proving quite difficult, considering there could be a nested Ctype(expression, Int32) within the regex match. Does anyone have any ideas for how to best go about doing this? Here is what I have now: Dim str As String = "CType((original.Width * CType((targetSize / CType(original.Height, Single)), Single)), Int32)" Dim exp As New Regex("CType\((.+), Int32\)") str = exp.Replace(str, "CInt($1)") But this will match the entire string and replace it. I was thinking of doing a recursive function to find the outer most match, and then work inwards, but that still presents a problem with things like CType(replaceChars(I), Int32)), Chr(CType(replacementChars(I), Int32) Any tips would be appreciated. Input returnString.Replace(Chr(CType(replaceChars(I), Int32)), Chr(CType(replacementChars(I), Int32))) Output: returnString.Replace(Chr(CInt(replaceChars(I))),Chr(CInt(replacementChars(I)))) Edit: Been working on it a little more and have a recursive function that I'm still working out the kinks in. Recursion + regex. it kinda hurts. Private Function FindReplaceCInts(ByVal strAs As String) As String System.Console.WriteLine(String.Format("Testing : {0}", strAs)) Dim exp As New Regex("CType\((.+), Int32\)") If exp.Match(strAs).Success Then For Each match As Match In exp.Matches(strAs) If exp.Match(match.Value.Substring(2)).Success Then Dim replaceT As String = match.Value.Substring(2) Dim Witht As String = FindReplaceCInts(match.Value.Substring(2)) System.Console.WriteLine(strAs.IndexOf(replaceT)) strAs.Replace(replaceT, Witht) End If Next strAs = exp.Replace(strAs, "CInt($1)") End If Return strAs End Function Cheers,

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  • R + Bioconductor : combining probesets in an ExpressionSet

    - by Mike Dewar
    Hi, First off, this may be the wrong Forum for this question, as it's pretty darn R+Bioconductor specific. Here's what I have: library('GEOquery') GDS = getGEO('GDS785') cd4T = GDS2eSet(GDS) cd4T <- cd4T[!fData(cd4T)$symbol == "",] Now cd4T is an ExpressionSet object which wraps a big matrix with 19794 rows (probesets) and 15 columns (samples). The final line gets rid of all probesets that do not have corresponding gene symbols. Now the trouble is that most genes in this set are assigned to more than one probeset. You can see this by doing gene_symbols = factor(fData(cd4T)$Gene.symbol) length(gene_symbols)-length(levels(gene_symbols)) [1] 6897 So only 6897 of my 19794 probesets have unique probeset - gene mappings. I'd like to somehow combine the expression levels of each probeset associated with each gene. I don't care much about the actual probe id for each probe. I'd like very much to end up with an ExpressionSet containing the merged information as all of my downstream analysis is designed to work with this class. I think I can write some code that will do this by hand, and make a new expression set from scratch. However, I'm assuming this can't be a new problem and that code exists to do it, using a statistically sound method to combine the gene expression levels. I'm guessing there's a proper name for this also but my googles aren't showing up much of use. Can anyone help?

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  • Powershell Regex help in extracting text between strings

    - by vivekeviv
    i Have an arguments like the one below which i pass to powershell script -arg1 -abc -def -arg2 -ghi -jkl -arg3 -123 -234 Now i need to extract three strings without any whitespace string 1: "-abc -def" string 2: "-ghi -jkl" string 3: "-123 -234" i figured this expression could do it. But this doesnt seem to work. $args -match '-arg1(?'arg1'.*?) -arg3(?'arg3'.*?) -arg3(?'arg3'.*)'. THis should return $matches['arg1'] etc. So whats wrong in above expression. Why do i get an error as shown below runScript.ps1 -arg1 -abc -def -arg2 -ghi -jkl -arg3 -123 -234 Unexpected token 'arg1'.?) -arg2 (?'arg2'.?) -arg3 (?'arg3'.)'' in expression or statement. At G:\powershell\tools\powershell\runTest.ps1:1 char:71 + $args -match '-arg1 (?'arg1'.?) -arg2 (?'arg2'.?) -arg3 (?'arg3'.)' <<<< + CategoryInfo : ParserError: (arg1'.?) -arg2...g3 (?'arg3'.)':String) [], ParseException + FullyQualifiedErrorId : UnexpectedToken and also the second question is how do i make arg1 or arg2 or arg3 optional? The argument to script can be -arg2 -def -ghi. I'll take some default values for arg(1|2|3) that is not mentioned. Thanks

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  • Flex special characters not embedding

    - by Hanpan
    Hi, I am using the following code to embed Arial into my application: [Embed(source='../assets/fonts/Arial.ttf',fontFamily='CustomFont',fontWeight='regular', unicodeRange='U+0020-U+0040,U+0041-U+005A,U+005B-U+0060,U+0061-U+007A,U+007B-U+007E,U+0080-U+00FF,U+0100-U+017F,U+0400-U+04FF,U+0370-U+03FF,U+1E00-U+1EFF,U+2022,U+2219,U+20AC-U+21AC', mimeType='application/x-font-truetype' )] public static var MY_FONT:Class; [Embed(source='../assets/fonts/Arial Bold.ttf',fontFamily='CustomFont',fontWeight='bold', unicodeRange='U+0020-U+0040,U+0041-U+005A,U+005B-U+0060,U+0061-U+007A,U+007B-U+007E,U+0080-U+00FF,U+0100-U+017F,U+0400-U+04FF,U+0370-U+03FF,U+1E00-U+1EFF,U+2022,U+2219,U+20AC-U+21AC', mimeType='application/x-font-truetype' )] public static var MY_FONT_BOLD:Class; [Embed(source='../assets/fonts/Arial Italic.ttf',fontFamily='CustomFont',fontWeight='regular',fontStyle="italic", unicodeRange='U+0020-U+0040,U+0041-U+005A,U+005B-U+0060,U+0061-U+007A,U+007B-U+007E,U+0080-U+00FF,U+0100-U+017F,U+0400-U+04FF,U+0370-U+03FF,U+1E00-U+1EFF,U+2022,U+2219,U+20AC-U+21AC', mimeType='application/x-font-truetype' )] public static var MY_FONT_ITALIC:Class; [Embed(source='../assets/fonts/Arial Bold Italic.ttf',fontFamily='CustomFont',fontWeight='bold',fontStyle="italic", unicodeRange='U+0020-U+0040,U+0041-U+005A,U+005B-U+0060,U+0061-U+007A,U+007B-U+007E,U+0080-U+00FF,U+0100-U+017F,U+0400-U+04FF,U+0370-U+03FF,U+1E00-U+1EFF,U+2022,U+2219,U+20AC-U+21AC', mimeType='application/x-font-truetype' )] public static var MY_FONT_ITALIC_BOLD:Class; [Embed(source='../assets/fonts/Arial Unicode.ttf',fontFamily='CustomFont',fontWeight='regular', unicodeRange='U+0020-U+0040,U+0041-U+005A,U+005B-U+0060,U+0061-U+007A,U+007B-U+007E,U+0080-U+00FF,U+0100-U+017F,U+0400-U+04FF,U+0370-U+03FF,U+1E00-U+1EFF,U+2022,U+2219,U+20AC-U+21AC', mimeType='application/x-font-truetype' )] public static var MY_FONT_UNICODE:Class; It's working fine for foreign characters, but no special characters (copyright, trademark, euro sign etc) are working. Can anyone help? I've checked my unicode ranges, they should work fine!

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  • compareTo and nested Enums

    - by echox
    Hi, in "A Programmers Guide to Java SCJP Certification" I found an example which I can't follow. This the given enum: enum Scale3 { GOOD(Grade.C), BETTER(Grade.B), BEST(Grade.A); enum Grade {A, B, C} private Grade grade; Scale3(Grade grade) { this.grade = grade; } public Grade getGrade() { return grade; } } This is the given expression: Scale3.GOOD.getGrade().compareTo(Scale3.Grade.A) > 0; I don't understand why this expression will be true? The return value will be 2. compareTo() will return a value 0 if the given object is "less" than the object. Scale3.Grade.A is the "biggest" element of Grades, its ordinal number is 0. Scale3.GOOD is the "biggest" element of Scale3, its ordinal number is also 0. The constructor of Scale3 is called with Scale3.Grade.C, which ordinal number is 2. So the given expression is equal to the following code: Scale3.Grade.C.compareTo(Scale3.Grade.A) > 0; A is "bigger" than C, so shouldn't be the result < 0?

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  • RegularExpression-esque search matching Objects in List

    - by Pindatjuh
    I'm currently working on an implementation of the following idea, and I was wondering if there is any literature on this subject. Working with Java, but the principle applies on any language with a decent type-system, I like to implement: matching Objects from a List using a RegularExpression-esque search: So let's say I have a List containing List<Object> x = new ArrayList<Object>(); x.add(new Object()); x.add("Hello World"); x.add("Second String"); x.add(5); // Integer (auto-boxing) x.add(6); // Integer Then I create a "Regular Expression" (not working with a stream of characters, but working with a stream of Objects), and instead of character-classes, I use type-system properties: [String][Integer] And this would match one sublist: {Match["Second String", 5]}. The expression: [String:length()<15] Will match two sublist (each of length 1) containing a String which instance is passing the expression instance.length() < 5: {Match["Hello World"],Match["Second String"]}. [Object][Object] Matches any pair in the List: {Match[Object,"Hello World"],Match["Second String", 5]}, in a streamed manner (no overlapping matches). Ofcourse, my implementation will have grouping, lookahead/lookbehinds and is hierarchical (i.e. matching n elements from Lists in Lists), etc. The above merely illustrates the concept. Is there a name for this principle, and is there literature available on it?

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  • latin1/unicode conversion problem with ajax request and special characters

    - by mfn
    Server is PHP5 and HTML charset is latin1 (iso-8859-1). With regular form POST requests, there's no problem with "special" characters like the em dash (–) for example. Although I don't know for sure, it works. Probably because there exists a representable character for the browser at char code 150 (which is what I see in PHP on the server for a literal em dash with ord). Now our application also provides some kind of preview mechanism via ajax: the text is sent to the server and a complete HTML for a preview is sent back. However, the ordinary char code 150 em dash character when sent via ajax (tested with GET and POST) mutates into something more: %E2%80%93. I see this already in the apache log. According to various sources I found, e.g. http://www.tachyonsoft.com/uc0020.htm , this is the UTF8 byte representation of em dash and my current knowledge is that JavaScript handles everything in Unicode. However within my app, I need everything in latin1. Simply said: just like a regular POST request would have given me that em dash as char code 150, I would need that for the translated UTF8 representation too. That's were I'm failing, because with PHP on the server when I try to decode it with either utf8_decode(...) or iconv('UTF-8', 'iso-8859-1', ...) but in both cases I get a regular ? representing this character (and iconv also throws me a notice: Detected an illegal character in input string ). My goal is to find an automated solution, but maybe I'm trying to be überclever in this case? I've found other people simply doing manual replacing with a predefined input/output set; but that would always give me the feeling I could loose characters. The observant reader will note that I'm behind on understanding the full impact/complexity with things about Unicode and conversion of chars and I definitely prefer to understand the thing as a whole then a simply manual mapping. thanks

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  • Recognizing terminals in a CFG production previously not defined as tokens.

    - by kmels
    I'm making a generator of LL(1) parsers, my input is a CoCo/R language specification. I've already got a Scanner generator for that input. Suppose I've got the following specification: COMPILER 1. CHARACTERS digit="0123456789". TOKENS number = digit{digit}. decnumber = digit{digit}"."digit{digit}. PRODUCTIONS Expression = Term{"+"Term|"-"Term}. Term = Factor{"*"Factor|"/"Factor}. Factor = ["-"](Number|"("Expression")"). Number = (number|decnumber). END 1. So, if the parser generated by this grammar receives a word "1+1", it'd be accepted i.e. a parse tree would be found. My question is, the character "+" was never defined in a token, but it appears in the non-terminal "Expression". How should my generated Scanner recognize it? It would not recognize it as a token. Is this a valid input then? Should I add this terminal in TOKENS and then consider an error routine for a Scanner for it to skip it? How does usual language specifications handle this?

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  • (x86) Assembler Optimization

    - by Pindatjuh
    I'm building a compiler/assembler/linker in Java for the x86-32 (IA32) processor targeting Windows. High-level concepts of a "language" (in essential a Java API for creating executables) are translated into opcodes, which then are wrapped and outputted to a file. The translation process has several phases, one is the translation between languages: the highest-level code is translated into the medium-level code which is then translated into the lowest-level code (probably more than 3 levels). My problem is the following; if I have higher-level code (X and Y) translated to lower-level code (x, y, U and V), then an example of such a translation is, in pseudo-code: x + U(f) // generated by X + V(f) + y // generated by Y (An easy example) where V is the opposite of U (compare with a stack push as U and a pop as V). This needs to be 'optimized' into: x + y (essentially removing the "useless" code) My idea was to use regular expressions. For the above case, it'll be a regular expression looking like this: x:(U(x)+V(x)):null, meaning for all x find U(x) followed by V(x) and replace by null. Imagine more complex regular expressions, for more complex optimizations. This should work on all levels. What do you suggest? What would be a good approach to optimize in these situations?

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  • Suggestions for a Cron like scheduler in Python?

    - by jamesh
    I'm looking for a library in Python which will provide at and cron like functionality. I'd quite like have a pure Python solution, rather than relying on tools installed on the box; this way I run on machines with no cron. For those unfamiliar with cron: you can schedule tasks based upon an expression like: 0 2 * * 7 /usr/bin/run-backup # run the backups at 0200 on Every Sunday 0 9-17/2 * * 1-5 /usr/bin/purge-temps # run the purge temps command, every 2 hours between 9am and 5pm on Mondays to Fridays. The cron time expression syntax is less important, but I would like to have something with this sort of flexibility. If there isn't something that does this for me out-the-box, any suggestions for the building blocks to make something like this would be gratefully received. Edit I'm not interested in launching processes, just "jobs" also written in Python - python functions. By necessity I think this would be a different thread, but not in a different process. To this end, I'm looking for the expressivity of the cron time expression, but in Python. Cron has been around for years, but I'm trying to be as portable as possible. I cannot rely on its presence.

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  • [grails] setting cookies when render type is "contentType: text/json"

    - by Robin Jamieson
    Is it possible to set cookies on response when the return render type is set as json? I can set cookies on the response object when returning with a standard render type and later on, I'm able to get it back on the subsequent request. However, if I were to set the cookies while rendering the return values as json, I can't seem to get back the cookie on the next request object. What's happening here? These two actions work as expected with 'basicForm' performing a regular form post to the action, 'withRegularSubmit', when the user clicks submit. // first action set the cookie and second action yields the originally set cookie def regularAction = { // using cookie plugin response.setCookie("username-regular", "regularCookieUser123",604800); return render(view: "basicForm"); } // called by form post def withRegularSubmit = { def myCookie = request.getCookie("username-regular"); // returns the value 'regularCookieUser123' return render(view: "resultView"); } When I switch to setting the cookie just before returning from the response with json, I don't get the cookie back with the post. The request starts by getting an html document that contains a form and when doc load event is fired, the following request is invoked via javascript with jQuery like this: var someUrl = "http://localhost/jsonAction"; $.get(someUrl, function(jsonData) { // do some work with javascript} The controller work: // this action is called initially and returns an html doc with a form. def loadJsonForm = { return render(view: "jsonForm"); } // called via javascript when the document load event is fired def jsonAction = { response.setCookie("username-json", "jsonCookieUser456",604800); // using cookie plugin return render(contentType:'text/json') { 'pair'('myKey': "someValue") }; } // called by form post def withJsonSubmit = { def myCookie = request.getCookie("username-json"); // got null value, expecting: jsonCookieUser456 return render(view: "resultView"); } The data is returned to the server as a result of the user pressing the 'submit' button and not through a script. Prior to the submit of both 'withRegularSubmit' and 'withJsonSubmit', I see the cookies stored in the browser (Firefox) so I know they reached the client.

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  • questions on nfa and dfa..

    - by Loop
    Hi Guys... Hope you help me with this one.... I have a main question which is ''how to judge whether a regular expression will be accepted by NFA and/or DFA? For eg. My question says that which of the regular expressions are equivalent? explain... 1.(a+b)*b(a+b)*b(a+b)* 2.a*ba*ba* 3.a*ba*b(a+b)* do we have to draw the NFA and DFA and then find through minimisation algorithm? if we do then how do we come to know that which regular expression is accepted by NFA/DFA so that we can begin with the answer? its so confusing.... Second is a very similar one, the question asks me to show that the language (a^nb^n|n1} is not accepted by DFA...grrrrr...how do i know this? (BTW this is a set of all strings of where a number of a's is followed by the same number of b's).... I hope I explained clearly well....

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  • I need to speed up a function. Should I use cython, ctypes, or something else?

    - by Peter Stewart
    I'm having a lot of fun learning Python by writing a genetic programming type of application. I've had some great advice from Torsten Marek, Paul Hankin and Alex Martelli on this site. The program has 4 main functions: generate (randomly) an expression tree. evaluate the fitness of the tree crossbreed mutate As all of generate, crossbreed and mutate call 'evaluate the fitness'. it is the busiest function and is the primary bottleneck speedwise. As is the nature of genetic algorithms, it has to search an immense solution space so the faster the better. I want to speed up each of these functions. I'll start with the fitness evaluator. My question is what is the best way to do this. I've been looking into cython, ctypes and 'linking and embedding'. They are all new to me and quite beyond me at the moment but I look forward to learning one and eventually all of them. The 'fitness function' needs to compare the value of the expression tree to the value of the target expression. So it will consist of a postfix evaluator which will read the tree in a postfix order. I have all the code in python. I need advice on which I should learn and use now: cython, ctypes or linking and embedding. Thank you.

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  • .NET Regex - Replace multiple characters at once without overwriting?

    - by Everaldo Aguiar
    I'm implementing a c# program that should automatize a Mono-alphabetic substitution cipher. The functionality i'm working on at the moment is the simplest one: The user will provide a plain text and a cipher alphabet, for example: Plain text(input): THIS IS A TEST Cipher alphabet: A - Y, H - Z, I - K, S - L, E - J, T - Q Cipher Text(output): QZKL KL QJLQ I thought of using regular expressions since I've been programming in perl for a while, but I'm encountering some problems on c#. First I would like to know if someone would have a suggestion for a regular expression that would replace all occurrence of each letter by its corresponding cipher letter (provided by user) at once and without overwriting anything. Example: In this case, user provides plaintext "TEST", and on his cipher alphabet, he wishes to have all his T's replaced with E's, E's replaced with Y and S replaced with J. My first thought was to substitute each occurrence of a letter with an individual character and then replace that character by the cipherletter corresponding to the plaintext letter provided. Using the same example word "TEST", the steps taken by the program to provide an answer would be: 1 - replace T's with (lets say) @ 2 - replace E's with # 3 - replace S's with & 4 - Replace @ with E, # with Y, & with j 5 - Output = EYJE This solution doesn't seem to work for large texts. I would like to know if anyone can think of a single regular expression that would allow me to replace each letter in a given text by its corresponding letter in a 26-letter cipher alphabet without the need of splitting the task in an intermediate step as I mentioned. If it helps visualize the process, this is a print screen of my GUI for the program:

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  • EF Many-to-many dbset.Include in DAL on GenericRepository

    - by Bryant
    I can't get the QueryObjectGraph to add INCLUDE child tables if my life depended on it...what am I missing? Stuck for third day on something that should be simple :-/ DAL: public abstract class RepositoryBase<T> where T : class { private MyLPL2Context dataContext; private readonly IDbSet<T> dbset; protected RepositoryBase(IDatabaseFactory databaseFactory) { DatabaseFactory = databaseFactory; dbset = DataContext.Set<T>(); DataContext.Configuration.LazyLoadingEnabled = true; } protected IDatabaseFactory DatabaseFactory { get; private set; } protected MyLPL2Context DataContext { get { return dataContext ?? (dataContext = DatabaseFactory.Get()); } } public IQueryable<T> QueryObjectGraph(Expression<Func<T, bool>> filter, params string[] children) { foreach (var child in children) { dbset.Include(child); } return dbset.Where(filter); } ... DAL repositories public interface IBreed_TranslatedSqlRepository : ISqlRepository<Breed_Translated> { } public class Breed_TranslatedSqlRepository : RepositoryBase<Breed_Translated>, IBreed_TranslatedSqlRepository { public Breed_TranslatedSqlRepository(IDatabaseFactory databaseFactory) : base(databaseFactory) {} } BLL Repo: public IQueryable<Breed_Translated> QueryObjectGraph(Expression<Func<Breed_Translated, bool>> filter, params string[] children) { return _r.QueryObjectGraph(filter, children); } Controller: var breeds1 = _breedTranslatedRepository .QueryObjectGraph(b => b.Culture == culture, new string[] { "AnimalType_Breed" }) .ToList(); I can't get to Breed.AnimalType_Breed.AnimalTypeId ..I can drill as far as Breed.AnimalType_Breed then the intelisense expects an expression? Cues if any, DB Tables: bold is many-to-many Breed, Breed_Translated, AnimalType_Breed, AnimalType, ...

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  • c# syntax and Linq, IQueryable

    - by hdiver
    Hello. This is a question about the SYNTAX of c# and NOT about how we call/use IQueryable Can someone please explain to me: We have this declaration (System.Linq): public static double Average<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, int>> selector) and to call the Average double average = fruits.AsQueryable().Average(s => s.Length); I understand how to call the Average and all the similar static method of IQueryable but I don’t understand the syntax of the declaration. public static double Average<TSource>(this IQueryable<TSource> source, Expression<Func<TSource, int>> selector) What does the <TSource> mean in Average<TSource>( and also the this IQueryable<TSource> source. since only one parameter passes when we call it and the actual lamda expression (s => s.Length); Thanks in advance.

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  • Does "epsilon" really guarantees anything in floating-point computations?!

    - by Michal Czardybon
    To make the problem short let's say I want to compute expression: a / (b - c) on float's. To make sure the result is meaningful, I can check if 'b' and 'c' are inequal: float eps = std::numeric_limits<float>::epsilon(); if ((b - c) > EPS || (c - b) > EPS) { return a / (b - c); } but my tests show it is not enough to guarantee either meaningful results nor not failing to provide a result if it is possible. Case 1: a = 1.0f; b = 0.00000003f; c = 0.00000002f; Result: The if condition is NOT met, but the expression would produce a correct result 100000008 (as for the floats' precision). Case 2: a = 1e33f; b = 0.000003; c = 0.000002; Result: The if condition is met, but the expression produces not a meaningful result +1.#INF00. I found it much more reliable to check the result, not the arguments: const float INF = numeric_limits<float>::infinity(); float x = a / (b - c); if (-INF < x && x < INF) { return x; } But what for is the epsilon then and why is everyone saying epsilon is good to use?

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  • Compiling a Windows C++ program in g++

    - by Phenom
    I'm trying to compile a Windows C++ program in g++. This is what I get. /usr/include/c++/4.4/backward/backward_warning.h:28:2: warning: #warning This file includes at least one deprecated or antiquated header which may be removed without further notice at a future date. Please use a non-deprecated interface with equivalent functionality instead. For a listing of replacement headers and interfaces, consult the file backward_warning.h. To disable this warning use -Wno-deprecated. btree.cpp:1204: error: ‘_TCHAR’ has not been declared btree.cpp: In function ‘int _tmain(int, int**)’: btree.cpp:1218: error: ‘__int64’ was not declared in this scope btree.cpp:1218: error: expected ‘;’ before ‘frequency’ btree.cpp:1220: error: ‘LARGE_INTEGER’ was not declared in this scope btree.cpp:1220: error: expected primary-expression before ‘)’ token btree.cpp:1220: error: ‘frequency’ was not declared in this scope btree.cpp:1220: error: ‘QueryPerformanceFrequency’ was not declared in this scope btree.cpp:1262: error: expected primary-expression before ‘)’ token btree.cpp:1262: error: ‘start’ was not declared in this scope btree.cpp:1262: error: ‘QueryPerformanceCounter’ was not declared in this scope btree.cpp:1264: error: name lookup of ‘i’ changed for ISO ‘for’ scoping btree.cpp:1264: note: (if you use ‘-fpermissive’ G++ will accept your code) btree.cpp:1304: error: expected primary-expression before ‘)’ token btree.cpp:1304: error: ‘end’ was not declared in this scope btree.cpp:1306: error: ‘total’ was not declared in this scope btree.cpp:1316: error: ‘getchar’ was not declared in this scope The first thing I noticed is that there are these variable types called _TCHAR, _int64, and LARGE_INTEGER, which is probably a Windows thing. What can these be changed to so that they will work in g++? Also, if there's anything else in here that you know can be converted to g++, that would be helpful. I got the code from here: http://touc.org/btree.html

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  • Can we have a component-scoped bean in a JSF2 composite component?

    - by Pradyumna
    Hi, I was wondering how I could create "component-scoped" beans, or so-to-say, "local variables inside a composite component" that are private to the instance of the composite component, and live as long as that instance lives. Below are more details, explained with an example: Suppose there is a "calculator" component - something that allows users to type in a mathematical expression, and evaluates its value. Optionally, it also plots the associated function. I can make a composite component that has: a text box for accepting the math expression two buttons called "Evaluate", and "Plot" another nested component that plots the function It is evidently a self-contained piece of function; so that somebody who wants to use it may just say <math:expressionEvaluator /> But obviously, the implementation would need a java object - something that evaluates the expression, something that computes the plot points, etc. - and I imagine it can be a bean - scoped just for this instance of this component, not a view-scoped or request-scoped bean that is shared across all instances of the component. How do I create such a bean? Is that even possible with composite components?

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