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  • How to match words as if in a dictionary, based on len-1 or len+1? Python

    - by pearbear
    If I have a word 'raqd', how would I use python to have a spellcheck, so to speak, to find the word 'rad' as an option in 'spellcheck'? What I've been trying to do is this: def isbettermatch(keysplit, searchword): i = 0 trues = 0 falses = 0 lensearchwords = len(searchword) keysplits = copy.deepcopy(keysplit) searchwords = copy.deepcopy(searchword) #print keysplit, searchwords if len(keysplits) == len(searchwords)-1: i = 0 while i < len(keysplits): j = 0 while j < lensearchwords: if keysplits[i] == searchwords[j]: trues +=1 searchwords.pop(j) lensearchwords = len(searchwords) elif keysplits[i] != searchwords[j]: falses +=1 j +=1 i +=1 if trues >= len(searchwords)-1: #print "-------------------------------------------------------", keysplits return True keysplit is a list like ['s', 'p', 'o', 'i', 'l'] for example, and the searchword would be a list ['r', 'a', 'q', 'd']. If the function returns True, then it would print the keyword that matches. Ex. 'rad', for the searchword 'raqd'. I need to find all possible matches for the searchword with a single letter addition or deletion. so ex. 'raqd' would have an option to be 'rad', and 'poted' could be 'posted' or 'potted'. Above is what I have tried, but it is not working well at all. Help much appreciated!

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  • Python OOP - object has no attribute

    - by user1744269
    I am attempting to learn how to program. I really do want to learn how to program; I love the building and design aspect of it. However, in Java and Python, I have tried and failed with programs as they pertain to objects, classes, methods.. I am trying to develop some code for a program, but im stumped. I know this is a simple error. However I am lost! I am hoping someone can guide me to a working program, but also help me learn (criticism is not only expected, but APPRECIATED). class Converter: def cTOf(self, numFrom): numFrom = self.numFrom numTo = (self.numFrom * (9/5)) + 32 print (str(numTo) + ' degrees Farenheit') return numTo def fTOc(self, numFrom): numFrom = self.numFrom numTo = ((numFrom - 32) * (5/9)) return numTo convert = Converter() numFrom = (float(input('Enter a number to convert.. '))) unitFrom = input('What unit would you like to convert from.. ') unitTo = input('What unit would you like to convert to.. ') if unitFrom == ('celcius'): convert.cTOf(numFrom) print(numTo) input('Please hit enter..') if unitFrom == ('farenheit'): convert.fTOc(numFrom) print(numTo) input('Please hit enter..')

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  • Python: Trouble with YACC

    - by Rosarch
    I'm parsing sentences like: "CS 2310 or equivalent experience" The desired output: [[("CS", 2310)], ["equivalent experience"]] YACC tokenizer symbols: tokens = [ 'DEPT_CODE', 'COURSE_NUMBER', 'OR_CONJ', 'MISC_TEXT', ] t_DEPT_CODE = r'[A-Z]{2,}' t_COURSE_NUMBER = r'[0-9]{4}' t_OR_CONJ = r'or' t_ignore = ' \t' terms = {'DEPT_CODE': t_DEPT_CODE, 'COURSE_NUMBER': t_COURSE_NUMBER, 'OR_CONJ': t_OR_CONJ} for name, regex in terms.items(): terms[name] = "^%s$" % regex def t_MISC_TEXT(t): r'\S+' for name, regex in terms.items(): # print "trying to match %s with regex %s" % (t.value, regex) if re.match(regex, t.value): t.type = name return t return t (MISC_TEXT is meant to match anything not caught by the other terms.) Some relevant rules from the parser: precedence = ( ('left', 'MISC_TEXT'), ) def p_statement_course_data(p): 'statement : course_data' p[0] = p[1] def p_course_data(p): 'course_data : course' p[0] = p[1] def p_course(p): 'course : DEPT_CODE COURSE_NUMBER' p[0] = make_course(p[1], int(p[2])) def p_or_phrase(p): 'or_phrase : statement OR_CONJ statement' p[0] = [[p[1]], [p[3]]] def p_misc_text(p): '''text_aggregate : MISC_TEXT MISC_TEXT | MISC_TEXT text_aggregate | text_aggregate MISC_TEXT ''' p[0] = "%s %s" % (p[0], [1]) def p_text_aggregate_statement(p): 'statement : text_aggregate' p[0] = p[1] Unfortunately, this fails: # works as it should >>> token_list("CS 2110 or equivalent experience") [LexToken(DEPT_CODE,'CS',1,0), LexToken(COURSE_NUMBER,'2110',1,3), LexToken(OR_CONJ,'or',1,8), LexToken(MISC_TEXT,'equivalent',1,11), LexToken(MISC_TEXT,'experience',1,22)] # fails. bummer. >>> parser.parse("CS 2110 or equivalent experience") Syntax error in input: LexToken(MISC_TEXT,'equivalent',1,11) What am I doing wrong? I don't fully understand how to set precedence rules. Also, this is my error function: def p_error(p): print "Syntax error in input: %s" % p Is there a way to see which rule the parser was trying when it failed? Or some other way to make the parser print which rules its trying?

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  • How to limit a user to entering 10 keywords or less using PHP & MySQL?

    - by G4TV
    I'm trying to limit my users to entering at least 10 keywords and was wondering how would I be able to do this using PHP & MySQL with my current Keyword script? Here is the add keywords PHP MySQL code. if (isset($_POST['tag']) && trim($_POST['tag'])!=='') { $tags = explode(",", $_POST['tag']); for ($x = 0; $x < count($tags); $x++){ $mysqli = mysqli_connect("localhost", "root", "", "sitename"); $query1 = "INSERT INTO tags (tag) VALUES ('" . mysqli_real_escape_string($mysqli, strtolower(htmlentities(trim(strip_tags($tags[$x]))))) . "')"; if (!mysqli_query($mysqli, $query1)) { print mysqli_error($mysqli); return; } $mysqli = mysqli_connect("localhost", "root", "", "sitename"); $dbc = mysqli_query($mysqli,"SELECT id FROM tags WHERE tag='" . mysqli_real_escape_string($mysqli, strtolower(htmlentities(trim(strip_tags($tags[$x]))))) . "'"); if (!$dbc) { print mysqli_error($mysqli); } else { while($row = mysqli_fetch_array($dbc)){ $id = $row["id"]; } } $query2 = "INSERT INTO question_tags (tag_id, question_id, user_id, date_created) VALUES ('$id', '$question', '$user', NOW())"; if (!mysqli_query($mysqli, $query2)) { print mysqli_error($mysqli); return; } } }

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  • Dynamic programming Approach- Knapsack Puzzle

    - by idalsin
    I'm trying to solve the Knapsack problem with the dynamical programming(DP) approach, with Python 3.x. My TA pointed us towards this code for a head start. I've tried to implement it, as below: def take_input(infile): f_open = open(infile, 'r') lines = [] for line in f_open: lines.append(line.strip()) f_open.close() return lines def create_list(jewel_lines): #turns the jewels into a list of lists jewels_list = [] for x in jewel_lines: weight = x.split()[0] value = x.split()[1] jewels_list.append((int(value), int(weight))) jewels_list = sorted(jewels_list, key = lambda x : (-x[0], x[1])) return jewels_list def dynamic_grab(items, max_weight): table = [[0 for weight in range(max_weight+1)] for j in range(len(items)+1)] for j in range(1,len(items)+1): val= items[j-1][0] wt= items[j-1][1] for weight in range(1, max_weight+1): if wt > weight: table[j][weight] = table[j-1][weight] else: table[j][weight] = max(table[j-1][weight],table[j-1][weight-wt] + val) result = [] weight = max_weight for j in range(len(items),0,-1): was_added = table[j][weight] != table[j-1][weight] if was_added: val = items[j-1][0] wt = items[j-1][1] result.append(items[j-1]) weight -= wt return result def totalvalue(comb): #total of a combo of items totwt = totval = 0 for val, wt in comb: totwt += wt totval += val return (totval, -totwt) if totwt <= max_weight else (0,0) #required setup of variables infile = "JT_test1.txt" given_input = take_input(infile) max_weight = int(given_input[0]) given_input.pop(0) jewels_list = create_list(given_input) #test lines print(jewels_list) print(greedy_grab(jewels_list, max_weight)) bagged = dynamic_grab(jewels_list, max_weight) print(totalvalue(bagged)) The sample case is below. It is in the format line[0] = bag_max, line[1:] is in form(weight, value): 575 125 3000 50 100 500 6000 25 30 I'm confused as to the logic of this code in that it returns me a tuple and I'm not sure what the output tuple represents. I've been looking at this for a while and just don't understand what the code is pointing me at. Any help would be appreciated.

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  • Python2.7: How can I speed up this bit of code (loop/lists/tuple optimization)?

    - by user89
    I repeat the following idiom again and again. I read from a large file (sometimes, up to 1.2 million records!) and store the output into an SQLite databse. Putting stuff into the SQLite DB seems to be fairly fast. def readerFunction(recordSize, recordFormat, connection, outputDirectory, outputFile, numObjects): insertString = "insert into NODE_DISP_INFO(node, analysis, timeStep, H1_translation, H2_translation, V_translation, H1_rotation, H2_rotation, V_rotation) values (?, ?, ?, ?, ?, ?, ?, ?, ?)" analysisNumber = int(outputPath[-3:]) outputFileObject = open(os.path.join(outputDirectory, outputFile), "rb") outputFileObject, numberOfRecordsInFileObject = determineNumberOfRecordsInFileObjectGivenRecordSize(recordSize, outputFileObject) numberOfRecordsPerObject = (numberOfRecordsInFileObject//numberOfObjects) loop1StartTime = time.time() for i in range(numberOfRecordsPerObject ): processedRecords = [] loop2StartTime = time.time() for j in range(numberOfObjects): fout = outputFileObject .read(recordSize) processedRecords.append(tuple([j+1, analysisNumber, i] + [x for x in list(struct.unpack(recordFormat, fout))])) loop2EndTime = time.time() print "Time taken to finish loop2: {}".format(loop2EndTime-loop2StartTime) dbInsertStartTime = time.time() connection.executemany(insertString, processedRecords) dbInsertEndTime = time.time() loop1EndTime = time.time() print "Time taken to finish loop1: {}".format(loop1EndTime-loop1StartTime) outputFileObject.close() print "Finished reading output file for analysis {}...".format(analysisNumber) When I run the code, it seems that "loop 2" and "inserting into the database" is where most execution time is spent. Average "loop 2" time is 0.003s, but it is run up to 50,000 times, in some analyses. The time spent putting stuff into the database is about the same: 0.004s. Currently, I am inserting into the database every time after loop2 finishes so that I don't have to deal with running out RAM. What could I do to speed up "loop 2"?

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  • Shell halts while looping and 'transforming' values in dictionary (Python 2.7.5)

    - by Gus
    I'm building a program that will sum digits in a given list in a recursive way. Say, if the source list has 10 elements, the second list will have 9, the third 8 and so on until the last list that will have only one element. This is done by adding the first element to the second, then the second to the third and so on. I'm stuck without feedback from the shell. It halts without throwing any errors, then in a couple of seconds the fan is spinning like crazy. I've read quite a few posts here and changed my approach, but I'm not sure that what have so far can produce the results I'm looking for. Thanks in advance: #--------------------------------------------------- #functions #--------------------------------------------------- #sum up pairs in a list def reduce(inputList): i = 0 while (i < len(inputList)): #ref to current and next item j = i + 1 #don't go for the last item if j != len(inputList): #new number eq current + next number newNumber = inputList[i] + inputList[j] if newNumber >= 10: #reduce newNumber to single digit newNumber = sum(map(int, str(newNumber))) #collect into temp list outputList.append(newNumber) i = i + 1 return outputList; #--------------------------------------------------- #program starts here #--------------------------------------------------- outputList = [] sourceList = [7, 3, 1, 2, 1, 4, 6] counter = len(sourceList) dict = {} dict[0] = sourceList print '-------------' print 'Level 0:', dict[0] for i in range(counter): j = i + 1 if j != counter: baseList = dict.get(i) #check function to understand what it does newList = reduce(baseList) #new key and value from previous/transformed value dict[j] = newList print 'Level %d: %s' % (j, dict[j])

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  • comparision of strings

    - by EmiLazE
    i am writing a program, that simulates game mastermind. but i am struggling on how to compare guessed pattern to key pattern. the game conditions are a little bit changed: patterns consist of letters. if an element of guessed pattern is equal to element of key pattern, and also index is equal, then print b. if an element of guessed pattern is equal to element of key pattern, but index is not, then print w. if an element of guessed pattern is not equal to element of key pattern, print dot. in feedback about guessed pattern, 'b's come first, 'w's second, '.'s last. my problem is that i cannot think of a way totally satisfies the answer. for (i=0; i<patternlength; i++) { for (x=0; x<patternlength; x++) { if (guess[i]==key[x] && i==x) printf("b"); if (guess[i]==key[x] && i!=x) printf("w"); if (guess[i]!=key[x]) printf("."); } }

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  • Java: Incompatible Types

    - by user2922081
    import java.text.*; import java.util.*; public class Proj3 { public static void main(String[]args){ // DecimalFormat df = new DecimalFormat("#0.00”); Scanner s = new Scanner(System.in); int TotalHours = 0; int TotalGrade = 0; System.out.print("How many courses did you take? "); int Courses = Integer.parseInt(s.nextLine()); System.out.println(""); int CourseNumber = Courses - (Courses - 1); while (Courses > 0){ System.out.print("Course (" + CourseNumber +"): How many hours? "); int Hours = Integer.parseInt(s.nextLine()); TotalHours = TotalHours + Hours; System.out.print("Course (" + CourseNumber +"): Letter grade? "); char Grade = s.nextLine().charAt(0); if (Grade == 'A'){ TotalGrade = TotalGrade + (4 * Hours); } if (Grade == 'B'){ TotalGrade = TotalGrade + (3 * Hours); } if (Grade == 'C'){ TotalGrade = TotalGrade + (2 * Hours); } if (Grade == 'D'){ TotalGrade = TotalGrade + (1 * Hours); } Courses = Courses - 1; CourseNumber = CourseNumber + 1; } Double GPA = TotalGrade / TotalHours; System.out.println(df.format(GPA)); } } This is for an assignment and I don't know how to fix my problem. The Double GPA = TotalGrade / ToutalHours; line is coming up with the Incompatible Types error. Also I'm supposed to include the DecimalFormat df = new DecimalFormat("#0.00”);line at the beginning of the main but its not working. Anything is very helpful. Thanks

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  • Custom DataAnnotation attribute with datastore access in ASP.NET MVC 2

    - by mare
    I have my application designed with Repository pattern implemented and my code prepared for optional dependency injection in future, if we need to support another datastore. I want to create a custom validation attribute for my content objects. This attribute should perform some kind of datastore lookup. For instance, I need my content to have unique slugs. To check if a Slug already exist, I want to use custom DataAnnotation attribute in my Base content object (instead of manually checking if a slug exists each time in my controller's Insert actions). Attribute logic would do the validation. So far I have come up with this: public class UniqueSlugAttribute : ValidationAttribute { private readonly IContentRepository _repository; public UniqueSlugAttribute(ContentType contentType) { _repository = new XmlContentRepository(contentType); } public override bool IsValid(object value) { if (string.IsNullOrWhiteSpace(value.ToString())) { return false; } string slug = value.ToString(); if(_repository.IsUniqueSlug(slug)) return true; return false; } } part of my Base content class: ... [DataMember] public ContentType ContentType1 { get; set; } [DataMember] [Required(ErrorMessageResourceType = typeof (Localize), ErrorMessageResourceName = "Validation_SlugIsBlank")] [UniqueSlug(ContentType1)] public string Slug { get { return _slug; } set { if (!string.IsNullOrEmpty(value)) _slug = Utility.RemoveIllegalCharacters(value); } } ... There's an error in line [UniqueSlug(ContentType1)] saying: "An attribute argument must be a constant expression, typeof expression or array creation expression of an attribute parameter type." Let me explain that I need to provide the ContentType1 parameter to the Constructor of UniqueSlug class because I use it in my data provider. It is actually the same error that appears if you try do to this on the built-in Required attribute: [Required(ErrorMessageResourceType = typeof (Localize), ErrorMessageResourceName = Resources.Localize.SlugRequired] It does not allow us to set it to dynamic content. In the first case ContentType1 gets known at runtime, in the second case the Resources.Localize.SlugRequired also gets known at runtime (because the Culture settings are assigned at runtime). This is really annoying and makes so many things and implementation scenarios impossible. So, my first question is, how to get rid of this error? The second question I have, is whether you think that I should redesign my validation code in any way?

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  • JMeter to grab full querystring into a variable for future use

    - by jfbauer
    Someone provided me the regex to parse out a query string: (?<=\?)[^?]+$ I am trying to use that in JMeter with no luck (although I am successful in pulling out individual query string parameter values based on various example postings on the web). I created a regular expression extractor called "Grab QueryString". I selected the URL response field to check. For the reference name, I typed "myQueryString". For the regular expression, I entered your text. For template, I entered $1$ Match no = 1 Default Value = ERROR Unfortunately, "myQueryString" is getting populated with ERROR and not the URL query string as hoped when I try and use it as a parameter in a future GET. Thus, I see this in the "View Results Tree": https:/www.website.com/folder/page.aspx?ERROR Instead of: https:/www.website.com/folder/page.aspx?jfhjHSDjgdjhsjhsdhjSJHWed Did I do something wrong? Anyone have any suggestions?

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  • Linq filtering an IQueryable<T> (System.Data.Linq.DataQuery) object by a List<T> (System.Collection.

    - by Klaptrap
    My IQueryable line is: // find all timesheets for this period - from db so System.Data.Linq.DataQuery var timesheets = _timesheetRepository.FindByPeriod(dte1, dte2); My List line is: // get my team from AD - from active directory so System.Collection.Generic.List var adUsers = _adUserRepository.GetMyTeam(User.Identity.Name); I wish to only show timesheets for those users in the timesheet collection that are present in the user collection. If I use a standard c# expression such as: var teamsheets = from t in timesheets join user in adUsers on t.User1.username equals user.fullname select t; I get the error "An IQueryable that returns a self-referencing Constant expression is not supported" Any recommendations?

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  • What is a proper way to pass a parameter to Set-Alias in powershell?

    - by Nick Gorbikoff
    Hello. A little background: I use PowerShell on windows xp at work and I set a bunch of useful shortcuts in Microsoft.PowerShell_profile.ps1 in My Documents, trying to emulate Mac environment inspired by Ryan Bates's shortcuts I have things like: Set-Alias rsc Rails-Console function Rails-Console {Invoke-Expression "ruby script/console"} Which works just fine when in command prompt I say: rsc #it calls the proper command However this doesn't work properly Set-Alias rsg Rails-Generate function Rails-Generate {Invoke-Expression "ruby script/generate"} So when I do : rsg model User which is supposed to call ruby script/generate model User all it calls is ruby script/generate #Dumping my params So how would I properly modify my functions to take params I send to functions? Thank you!!

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  • not able to do max width

    - by Pradyut Bhattacharya
    Hi I have a page which has a content like this... <div id="content"> testingtestingtestingtestingtestingtestingtestingtestingtesting testingtestingtestingtestingtestingtestingtestingtesting testingtestingtestingtestingtesting </div> How do i apply a max-width on it . I m using this code in the css #content { max-width:50px; /* for standards-compliant browsers */ /*width:expression(document.body.clientwidth > 650? "650px": "auto" );*/ /* max-width expression for IE only */ } but i m not getting the results in firefox... http://pradyut.dyndns.org/WebApplicationSecurity/width.jsp Are there any JavaScript solutions? Any help thanks Pradyut

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  • Haskell Convert Byte String To UTC Time

    - by Steve
    I have been trying to make a function in Haskell to take a ByteString which is a datetime and convert it to UTC time taking into account the time zone from the original encoding. I am very new to Haskell so I may be making a really basic mistake. convertStringToUtc s = do estTimeZone <- hoursToTimeZone -5 time <- read $ B.unpack(s) localTimeToUTC estTimeZone time The error I get is: Couldn't match expected type `Int -> b' against inferred type `UTCTime' In the expression: localTimeToUTC estTimeZone time In the expression: do { estTimeZone <- hoursToTimeZone - 5; time <- read $ B.unpack (s); localTimeToUTC estTimeZone time }

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  • Ambiguous call between methods ASP.NET MVC

    - by GuiPereira
    I'm pretty new in ASP.NET MVC (about 3 months) and i've the followin issue: I have a Entity Class called 'Usuario' in a ClassLibrary referenced as 'Core' and, when i create a strongly-typed view and add a html.textboxfor< like: <%= Html.TextBoxFor(u => u.Login) %> it raises the following error: Error 3 The call is ambiguous between the following methods or properties: 'Microsoft.Web.Mvc.ExpressionInputExtensions.TextBoxFor<Core.Usuario,string>(System.Web.Mvc .HtmlHelper<Core.Usuario>, System.Linq.Expressions.Expression<System.Func<Core.Usuario,string>>)' and 'System.Web.Mvc.Html.InputExtensions.TextBoxFor<Core.Usuario,string>(System.Web.Mvc.HtmlHel per<Core.Usuario>, System.Linq.Expressions.Expression<System.Func<Core.Usuario,string>>)' d:\Documents\Visual Studio 2008\Projects\GuiPereiraMVC2\GuiPereiraMVC2\Views\Gestao\Index.aspx 20 25 GuiPereiraMVC2 anyone knows why?

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  • Checking attribute exists in JSP

    - by Javi
    Hello, I have some classes which extends a superclass, and in the JSP I want to show some attributes of these classes. I only want to make one JSP, but I don't know in advance if the object has an attribute or not. So I need a JSTL expression or a tag which checks that the object I pass has this attribute (similar to in operator in javascript, but in the server). <c:if test="${an expression which checks if myAttribute exists in myObject}"> <!-- Display this only when myObject has the atttribute "myAttribute" --> <!-- Now I can access safely to "myAttribute" --> ${myObject.myAttribute} </C:if> How can I get this? Thanks.

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  • how to group by over anonymous type with vb.net linq to object

    - by smoothdeveloper
    I'm trying to write a linq to object query in vb.net, here is the c# version of what I'm trying to achieve (I'm running this in linqpad): void Main() { var items = GetArray( new {a="a",b="a",c=1} , new {a="a",b="a",c=2} , new {a="a",b="b",c=1} ); ( from i in items group i by new {i.a, i.b} into g let p = new{ k = g, v = g.Sum((i)=>i.c)} where p.v > 1 select p ).Dump(); } // because vb.net doesn't support anonymous type array initializer, it will ease the translation T[] GetArray<T>(params T[] values){ return values; } I'm having hard time with either the group by syntax which is not the same (vb require 'identifier = expression' at some places, as well as with the summing functor with 'expression required' ) Thanks so much for your help!

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  • Powershell: align right for a column value from Select-Object in Format-Table format

    - by David.Chu.ca
    I have the following array value $outData with several columns. I am not sure how I align some columns right? $outData | Select-Object ` Name ` @{Name="Freespace(byte)"; Expression={"{0:N0}" -f $_.FreeSpace}}, ' .... # other colums ` | Format-Table -AutoSize It works fine. However, when I tried to use align for the freespace column to right: @{Name="Freespace(byte)"; Expression={"{0:N0}" -f $_.FreeSpace}; align="right"}, ' I got error message "Specified method is not supported". Not sure if there is any way to align the value to right?

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  • Regular expressions in URL Rewrite Module for IIS7

    - by TN
    I have following rewrite rule to append .aspx extension if url has no extension. <rule name="SimpleRewrite" stopProcessing="true"> <match url="^(.*(?&lt;=/)([^/.]*))$" /> <action type="Rewrite" url="{R:1}.aspx" /> </rule> However the rule is not working: Error HTTP 500.52 - URL Rewrite Module Error. The expression "^(.*(?<=/)([^/.]*))$" has an invalid syntax. However, this regular expression works in .NET. What regular expressions are supported by IIS Url Rewrite Module? How to make positive lookbehind assertion?

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  • What is a Perl regex for finding the first non-consecutively-repeating character in a string.

    - by DVK
    Your task, should you choose to accept it, is to write a Perl regular expression that for a given string, will return the first occurence of a character that is not consecutively duplicated. In other words, both preceded AND succeeded by characters different from itself (or start/end of string respectively). Example: IN: aabbcdecc OUT: c Please note that "not consecutively duplicated" does not mean "anywhere in the string". NOTE: it must be a pure regex expression. E.g. the solution that obviously comes to mind (clone the string, delete all the duplicates, and print the first remaining character) does not count, although it solves the problem. The question is inspired by my somewhat off-topic answer to this: http://stackoverflow.com/questions/2548606/perl-function-to-find-first-non-repeating-character-in-a-string

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  • Haskell: how to get through 'no instance for' ?

    - by artemave
    I am learning Haskell. I am on the 8th chapter of this book. The main thing I've learned so far is that Haskell is very unfriendly to me and it bites my ass where possible. Moreover... Heck! Enough mourning, to business. Here is the code: module GlobRegex ( globToRegex, matchesGlob ) where import Text.Regex.Posix import Text.Regex.Posix.String import Text.Regex.Base.RegexLike data CaseOpt = Case | NoCase deriving (Eq) matchesGlob :: String -> String -> CaseOpt -> Bool matchesGlob name pat caseopt = match regex name where regex = case caseopt of NoCase -> makeRegexOpts (defaultCompOpt + compIgnoreCase) defaultExecOpt (globToRegex pat) Case -> makeRegex (globToRegex pat) globToRegex :: String -> String ... And here is how it fails to compile: Prelude Text.Regex.Posix Text.Regex.Base.RegexLike> :load globtoregex\GlobRegex. hs [1 of 1] Compiling GlobRegex ( globtoregex\GlobRegex.hs, interpreted ) globtoregex\GlobRegex.hs:14:31: No instance for (RegexLike regex [Char]) arising from a use of `match' at globtoregex\GlobRegex.hs:14:31-46 Possible fix: add an instance declaration for (RegexLike regex [Char]) In the expression: match regex name In the definition of `matchesGlob': matchesGlob name pat caseopt = match regex name where regex = case caseopt of { NoCase -> makeRegexOpts (defaultCompOpt + compIgnoreCase) defaultExecOpt (globToRegex pat) Case -> makeRegex (globToRegex pat) } globtoregex\GlobRegex.hs:17:23: No instance for (RegexMaker regex CompOption execOpt String) arising from a use of `makeRegex' at globtoregex\GlobRegex.hs:17:23-49 Possible fix: add an instance declaration for (RegexMaker regex CompOption execOpt String) In the expression: makeRegex (globToRegex pat) In a case alternative: Case -> makeRegex (globToRegex pat) In the expression: case caseopt of { NoCase -> makeRegexOpts (defaultCompOpt + compIgnoreCase) defaultExecOpt (globToRegex p at) Case -> makeRegex (globToRegex pat) } Failed, modules loaded: none. To my best understanding, Text.Regex.Posix.String provides instances for RegexLike Regex String and RegexMaker Regex CompOption ExecOption String, so it should work. On the other hand, I can see that regex in the error message is type variable, not a concrete type, so, perhaps not... Anyway, this is where I am stuck. May be there is a common pattern for resolving no instance for type of problems? Or, in Haskell terms, instance of SmartGuess typeclass for no instance for?

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  • RIA Services Repository Save does not work!?

    - by Savvas Sopiadis
    Hello everybody! Doing my first SL4 MVVM RIA based application and i ran into the following situation: updating a record (EF4,NO-POCOS!!) in the SL-client seems to take place, but values in the dbms are unchanged. Debugging with Fiddler the message on save is (amongst others): EntityActions.nil? b9http://schemas.microsoft.com/2003/10/Serialization/Arrays^HasMemberChanges?^Id?^ Operation?Update I assume that this says only: hey! the dbms should do an update on this record, AND nothing more! Is that right?! I 'm using a generic repository like this: public class Repository<T> : IRepository<T> where T : class { IObjectSet<T> _objectSet; IObjectContext _objectContext; public Repository(IObjectContext objectContext) { this._objectContext = objectContext; _objectSet = objectContext.CreateObjectSet<T>(); } public IQueryable<T> AsQueryable() { return _objectSet; } public IEnumerable<T> GetAll() { return _objectSet.ToList(); } public IEnumerable<T> Find(Expression<Func<T, bool>> where) { return _objectSet.Where(where); } public T Single(Expression<Func<T, bool>> where) { return _objectSet.Single(where); } public T First(Expression<Func<T, bool>> where) { return _objectSet.First(where); } public void Delete(T entity) { _objectSet.DeleteObject(entity); } public void Add(T entity) { _objectSet.AddObject(entity); } public void Attach(T entity) { _objectSet.Attach(entity); } public void Save() { _objectContext.SaveChanges(); } } The DomainService Update Method is the following: [Update] public void UpdateCulture(Culture currentCulture) { if (currentCulture.EntityState == System.Data.EntityState.Detached) { this.cultureRepository.Attach(currentCulture); } this.cultureRepository.Save(); } I know that the currentCulture-Entity is detached. What confuses me (amongst other things) is this: is the _objectContext still alive? (which means it "will be"??? aware of the changes made to record, so simply calling Attach() and then Save() should be enough!?!?) What am i missing? Development Environment: VS2010RC - Entity Framework 4 (no POCOs) Thanks in advance

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