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• Specify fields in a recursive find with cakephp

  - by Razor Storm

  Suppose I have a table Recipe that hasmany ingredients. I do a recursive find to grab recipes with their associated ingredients: $this->Recipe->find('all', array('fields' => array('id','title','description'))); Here I can use the 'fields' attribute to specify that I only want it to return id, title, and description. However, despite this, cakephp still returns ALL columns from the ingredients table. How do I tell cakephp that I only want ingredient table's id and name fields? btw ingredient model is "Ingredient" and the table is ingredients, and the aggregation table is recipes_ingredients.

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• C: Recursive function for inverting an int

  - by Jorge

  I had this problem on an exam yesterday. I couldn't resolve it so you can imagine the result... Make a recursive function: int invertint( int num) that will receive an integer and return it but inverted, example: 321 would return as 123 I wrote this: int invertint( int num ) { int rest = num % 10; int div = num / 10; if( div == 0 ) { return( rest ); } return( rest * 10 + invert( div ) ) } Worked for 2 digits numbers but not for 3 digits or more. Since 321 would return 1 * 10 + 23 in the last stage. Thanks a lot! PS: Is there a way to understand these kind of recursion problems in a faster manner or it's up to imagination of one self?

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• Segmentation fault C++ in recursive function

  - by user69514

  Why do I get a segmentation fault in my recursive function. It happens every time i call it when a value greater than 4 as a parameter #include <iostream> #include <limits> using namespace std; int printSeries(int n){ if(n==1){ return 1; } else if( n==2){ return 2; } else if( n==3){ return 3; } else if( n==4){ return printSeries(1) + printSeries(2) + printSeries(3); } else{ return printSeries(n-3) + printSeries((n-2) + printSeries(n-1)); } } int main(){ //double infinity = numeric_limits<double>::max(); for(int i=1; i<=10; i++){ cout << printSeries(i) << endl; } return 0; }

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• Write a recursive function in C that converts a number into a string

  - by user3501779

  I'm studying software engineering, and came across this exercise: it asks to write a recursive function in C language that receives a positive integer and an empty string, and "translates" the number into a string. Meaning that after calling the function, the string we sent would contain the number but as a string of its digits. I wrote this function, but when I tried printing the string, it did print the number I sent, but in reverse. This is the function: void strnum(int n, char *str) { if(n) { strnum(n/10, str+1); *str = n%10 + '0'; } } For example, I sent the number 123 on function call, and the output was 321 instead of 123. I also tried exchanging the two lines within the if statement, and it still does the same. I can't figure out what I did wrong. Can someone help please? NOTE: Use of while and for loop statements is not allowed for the exercise.

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• Recursive solution to finding patterns

  - by user2997162

  I was solving a problem on recursion which is to count the total number of consecutive 8's in a number. For example: input: 8801 output: 2 input: 801 output: 0 input: 888 output: 3 input: 88088018 output:4 I am unable to figure out the logic of passing the information to the next recursive call about whether the previous digit was an 8. I do not want the code but I need help with the logic. For an iterative solution, I could have used a flag variable, but in recursion how do I do the work which flag variable does in an iterative solution. Also, it is not a part of any assignment. This just came to my mind because I am trying to practice coding using recursion.

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• wget: Turn Off Forced .html Retreival

  - by Mike B

  When performing a recursive download, I specify a pattern via the -R parameter for wget to reject, but if this file is a HTML file, wget downloads the file regardless of whether or not it matches the pattern. e.g. wget -r -R "*dynamicfile*" example.com still retrieves files such as example.com/dynamicfile1.html Is there a way to prevent this?

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• Ignore .svn when doing `diff -r`

  - by Sridhar Ratnakumar

  diff has an option --recursive (-r) to do a comparison between two directories (the files inside them). Is there a way to make diff ignore certain sub-directories (eg: .svn)? $ diff -r src1/ src2/

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• Trying to exclude certain extensions doing a recursive copy (MSBuild)

  - by Kragen

  I'm trying to use MSBuild to read in a list of files from a text file, and then perform a recursive copy, copying the contents of those directories files to some staging area, while excluding certain extensions (e.g. .tmp files) I've managed to do most of the above quite easily using CreateItem and the MSBuild copy task, whatever I do the CreateItem task just ignores my Exclude parameter: <PropertyGroup> <RootFolder>c:\temp</RootFolder> <ExcludeFilter>*.tmp</ExcludeFilter> <StagingDirectory>staging</StagingDirectory> </PropertyGroup> <ItemGroup> <InputFile Include="MyFile.txt" /> </ItemGroup> <Target Name="Build"> <ReadLinesFromFile File="@(InputFile)"> <Output ItemName="AllFolders" TaskParameter="Lines" /> </ReadLinesFromFile> <CreateItem Include="$(RootFolder)\%(AllFolders.RelativeDir)**" Exclude="$(ExcludeFilter)"> <Output ItemName="AllFiles" TaskParameter="Include" /> </CreateItem> <Copy SourceFiles="@(AllFiles)" DestinationFolder="$(StagingDirectory)\%(RecursiveDir)" Example contents of 'MyFile.txt': somedirectory\ someotherdirectory\ (I.e. the paths are relative to $(RootFolder) - mention this because I read somewhere that it might be relevant) I've tried loads of different combinations of Exclude filters, but I never seem to be able to get it to correctly exclude my .tmp files - is there any way of doing this with MSBuild without resorting to xcopy?

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• Build System with Recursive Dependency Aggregation

  - by radman

  Hi, I recently began setting up my own library and projects using a cross platform build system (generates make files, visual studio solutions/projects etc on demand) and I have run into a problem that has likely been solved already. The issue that I have run into is this: When an application has a dependency that also has dependencies then the application being linked must link the dependency and also all of its sub-dependencies. This proceeds in a recursive fashion e.g. (For arguments sake lets assume that we are dealing exclusively with static libraries.) TopLevelApp.exe dependency_A dependency_A-1 dependency_A-2 dependency_B dependency_B-1 dependency_B-2 So in this example TopLevelApp will need to link dependency_A, dependency_A-1, dependency_A-2 etc and the same for B. I think the responsibility of remembering all of these manually in the target application is pretty sub optimal. There is also the issue of ensuring the same version of the dependency is used across all targets (assuming that some targets depend on the same things, e.g. boost). Now linking all of the libraries is required and there is no way of getting around it. What I am looking for is a build system that manages this for you. So all you have to do is specify that you depend on something and the appropriate dependencies of that library will be pulled in automatically. The build system I have been looking at is premake premake4 which doesn't handle this (as far as I can determine). Does anyone know of a build system that does handle this? and if there isn't then why not?

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• Java: dangerous self-returning-recursive function by IOException?

  - by HH

  I had very errorsome Exception handling with if-clauses. An exception occurs if not found path. An exception returns the function again. The function is recursive. Safe? $ javac SubDirs.java $ java SubDirs Give me an path. . HELLO com TOASHEOU google common annotations base collect internal Give me an path. IT WON'T FIND ME, SO IT RETURNS ITSELF due to Exception caught Give me an path. $ cat SubDirs.java import java.io.*; import java.util.*; public class SubDirs { private List<File> getSubdirs(File file) throws IOException { List<File> subdirs = Arrays.asList(file.listFiles(new FileFilter() { public boolean accept(File f) { return f.isDirectory(); } })); subdirs = new ArrayList<File>(subdirs); List<File> deepSubdirs = new ArrayList<File>(); for(File subdir : subdirs) { deepSubdirs.addAll(getSubdirs(subdir)); } subdirs.addAll(deepSubdirs); return subdirs; } public static void search() { try{ BufferedReader in = new BufferedReader(new InputStreamReader(System.in)); String s; System.out.println("Give me an path."); while ((s = in.readLine()) != null && s.length() != 0){ SubDirs dirs = new SubDirs(); List<File> subDirs = dirs.getSubdirs(new File(s)); for ( File f : subDirs ) { System.out.println(f.getName()); } System.out.println("Give me an path."); } }catch(Exception e){ // Simple but is it safe? search(); } } public static void main(String[] args) throws IOException { search(); } }

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• Recursive Perl detail need help

  - by Catarrunas

  Hi everybody, i think this is a simple problem, but i'm stuck with it for some time now! I need a fresh pair of eyes on this. The thing is i have this code in perl: #!c:/Perl/bin/perl use CGI qw/param/; use URI::Escape; print "Content-type: text/html\n\n"; my $directory = param ('directory'); $directory = uri_unescape ($directory); my @contents; readDir($directory); foreach (@contents) { print "$_\n"; } #------------------------------------------------------------------------ sub readDir(){ my $dir = shift; opendir(DIR, $dir) or die $!; while (my $file = readdir(DIR)) { next if ($file =~ m/^\./); if(-d $dir.$file) { #print $dir.$file. " ----- DIR\n"; readDir($dir.$file); } push @contents, ($dir . $file); } closedir(DIR); } I've tried to make it recursive. I need to have all the files of all of the directories and subdirectories, with the full path, so that i can open the files in the future. But my output only returns the files in the current directory and the files in the first directory that it finds. If i have 3 folders inside the directory it only shows the first one. Ex. of cmd call: "perl readDir.pl directory=C:/PerlTest/" Thanks

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• Grails - Recursive computing call "StackOverflowError" and don't update on show

  - by Kedare

  Hello, I have a little problem, I have made a Category domain on Grails, but I want to "cache" the string representation on the database by generating it when the representation field is empty or NULL (to avoid recursive queries at each toString), here is the code : package devkedare class Category { String title; String description; String representation; Date dateCreated; Date lastUpdate; Category parent; static constraints = { title(blank:false, nullable:false, size:2..100); description(blank:true, nullable:false); dateCreated(nullable:true); lastUpdate(nullable:true); autoTimestamp: true; } static hasMany = [childs:Category] @Override String toString() { if((!this.representation) || (this.representation == "")) { this.computeRepresentation(true) } return this.representation; } String computeRepresentation(boolean updateChilds) { if(updateChilds) { for(child in this.childs) { child.representation = child.computeRepresentation(true); } } if(this.parent) { this.representation = "${this.parent.computeRepresentation(false)}/${this.title}"; } else { this.representation = this.title } return this.representation; } void beforeUpdate() { this.computeRepresentation(true); } } There is 2 problems : It don't update the representation when the representation if NULL or empty and toString id called, it only update it on save, how to fix that ? On some category, updating it throw a StackOverflowError, here is an example of my actual category table as CSV : Uploaded the csv file here, pasting csv looks buggy: http://kedare.free.fr/Dist/01.csv Updating the representation works everywhere except on "IT" that throw a StackOverlowError (this is the only category that has many childs). Any idea of how can I fix those 2 problems ? Thank you !

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• Need some help to determine the amount of recursive calls in PHP

  - by Ben Fransen

  Hi all, I've got a, I think fairly easy question, but this is bugging me for a while now. So I figured, maybe I can get some help here. Since recursive functions are always a bit tricky, and sometimes a bit unclear to me, I keep struggling to create a nice working solution to get my menudata. In one of my classes I have this function, which gives me all menu-items recursivly. The thing I want is to determine at which recursionlevel a certain object was retrieved so I can create a nicely looking HTML output with indents for the levels of nesting. public function GetObjectList($parentID = 0, $objectlist = null) { if(is_null($objectlist)) { $objectlist = new ObjectList("Model_Navigation"); } $query = MySQL::Query("SELECT * FROM `Navigation` WHERE `WebsiteID` = ".SITE_ID. " AND `LanguageID` = ".LANG_ID." AND `ParentID` = ".$parentID); while($result = MySQL::FetchAssoc($query)) { $object = new Model_Navigation(); $object->ID = $result["ID"]; $object->WebsiteID = $result["WebsiteID"]; $object->LanguageID = $result["LanguageID"]; $object->ParentID = $result["ParentID"]; $object->Name = $result["Name"]; $object->Page = Model_Page::GetObjectByID($result["PageID"]); $object->ExternalURL = $result["ExternalURL"]; $object->Index = $result["Index"]; $object->Level = [here lies my problem]; $objectlist->Add($object); self::GetObjectList($object->ID, $objectlist); } return $objectlist; } Hope to hear from you! Greetings from Holland, Ben Fransen

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• WPF - DataTemplate to show only one hierarchical level in recursive data

  - by Paull

  Hi all, I am using a tree to display my data: persons grouped by their teams. In my model a team can contain another team, so the recursion. I want do display details about the selected node of the tree using a contentpresenter. If the selection is a person, everything is fine: I can show the person name or datails without problem using a simple datatemplate. If the selection is a team I would like to display the team name followed by a list of member names. If one of these members is another team I would like to display just the team name, without recursion... My code here is wrong because it displays data in a recursive way, what is the right way of doing it? Thanks in advance for any help! best regards, Paolo <ContentPresenter Content="{Binding Path=SelectedItem, ElementName=PeopleTree}" > <ContentPresenter.Resources> <DataTemplate DataType="{x:Type my:PersonViewModel}"> <TextBlock Text="{Binding PersonName}"/> </DataTemplate> <DataTemplate DataType="{x:Type my:TeamViewModel}"> <StackPanel> <TextBlock Text="{Binding TeamName}" /> <ListBox ItemsSource="{Binding Members}" /> </StackPanel> </DataTemplate> </ContentPresenter.Resources> </ContentPresenter>

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• Recursive list of lists in XSL

  - by Paul Tomblin

  I have a recursive nodes that I'm trying to set up for jquery-checktree. The nodes look like foo/bar/ID /NAME /CHECKED bar/ID /NAME /CHECKED /bar/ID /NAME /bar/ID /NAME /bar/ID /NAME /CHECKED /bar/ID /NAME /CHECKED Where any bar may or may not have one or more bar nodes below it, but any bar will have ID and NAME and might have a CHECKED. and I want to turn that into <ul> <li><input type="checkbox" name="..." value="..." checked="checked"></input> <label for="...">...</label> <ul> <li><input type="checkbox" name="..." value="..." checked="checked"></input> <label for="...">...</label> </li> </ul> <li>....</li> </ul> I can get the first level by doing: <ul class="tree"> <xsl:for-each select="/foo/bar/"> <li><input type="checkbox" name="{ID}" value="{ID}"> <xsl:if test="CHECKED = 'Y'"><xsl:attribute name="checked">checked</xsl:attribute></xsl:if> </input><label for="{ID}"><xsl:value-of select="NAME"/></label> </li> </xsl:for-each> </ul> But I don't know how to recurse down to the embedded "bar" within the "bar", down to however many levels there might be.

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• How can I order by the result of a recursive SQL query

  - by Tony

  I have the following method I need to ORDER BY: def has_attachments? attachments.size > 0 || (!parent.nil? && parent.has_attachments?) end I have gotten this far: ORDER BY CASE WHEN attachments.size > 0 THEN 1 ELSE (CASE WHEN parent_id IS NULL THEN 0 ELSE (CASE message.parent ...what goes here ) END END END I may be looking at this wrong because I don't have experience with recursive SQL. Essentially I want to ORDER by whether a message or any of its parents has attachments. If it's attachment size is 0, I can stop and return a 1. If the message has an attachment size of 0, I now check to see if it has a parent. If it has no parent then there is no attachment, however if it does have a parent then I essentially have to do the same query case logic for the parent. UPDATE The table looks like this +---------------------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +---------------------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | message_type_id | int(11) | NO | MUL | | | | message_priority_id | int(11) | NO | MUL | | | | message_status_id | int(11) | NO | MUL | | | | message_subject_id | int(11) | NO | MUL | | | | from_user_id | int(11) | YES | MUL | NULL | | | parent_id | int(11) | YES | MUL | NULL | | | expires_at | datetime | YES | MUL | NULL | | | subject_other | varchar(255) | YES | | NULL | | | body | text | YES | | NULL | | | created_at | datetime | NO | MUL | | | | updated_at | datetime | NO | | | | | lock_version | int(11) | NO | | 0 | | +---------------------+--------------+------+-----+---------+----------------+ Where the parent_id refers to the parent message, if it exists. Thanks!

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• What would be different in Java if Enum declaration didn't have the recursive part

  - by atamur

  Please see http://stackoverflow.com/questions/211143/java-enum-definition and http://stackoverflow.com/questions/3061759/why-in-java-enum-is-declared-as-enume-extends-enume for general discussion. Here I would like to learn what exactly would be broken (not typesafe anymore, or requiring additional casts etc) if Enum class was defined as public class Enum<E extends Enum> I'm using this code for testing my ideas: interface MyComparable<T> { int myCompare(T o); } class MyEnum<E extends MyEnum> implements MyComparable<E> { public int myCompare(E o) { return -1; } } class FirstEnum extends MyEnum<FirstEnum> {} class SecondEnum extends MyEnum<SecondEnum> {} With it I wasn't able to find any benefits in this exact case. PS. the fact that I'm not allowed to do class ThirdEnum extends MyEnum<SecondEnum> {} when MyEnum is defined with recursion is a) not relevant, because with real enums you are not allowed to do that just because you can't extend enum yourself b) not true - pls try it in a compiler and see that it in fact is able to compile w/o any errors PPS. I'm more and more inclined to believe that the correct answer here would be "nothing would change if you remove the recursive part" - but I just can't believe that.

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• Stop an executing recursive javascript function

  - by DA

  Using jQuery, I've build an image/slide rotator. The basic setup is (in pseudocode): function setupUpSlide(SlideToStartWith){ var thisSlide = SlideToStartWith; ...set things up... fadeInSlide(thisSlide) } function fadeInSlide(thisSlide){ ...fade in this slide... fadeOutSlide(thisSlide) } function fadeOutSlide(thisSlide){ ...fade out this slide... setupUpSlide(nextSlide) } I call the first function and pass in a particular slide index, and then it does its thing calling chain of functions which then, in turn, calls the first function again passing in the next index. This then repeats infinitely (resetting the index when it gets to the last item). This works just fine. What I want to do now is allow someone to over-ride the slide show by being able to click on a particular slide number. Therefore, if slide #8 is showing and I click #3, I want the recursion to stop and then call the initial function passing in slide #3, which then, in turn, will start the process again. But I'm not sure how to go about that. How does one properly 'break' a recursive script. Should I create some sort of global 'watch' variable that if at any time is 'true' will return: false and allow the new function to execute?

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• Recursive QuickSort suffering a StackOverflowException -- Need fresh eyes

  - by jon

  I am working on a Recursive QuickSort method implementation in a GenericList Class. I will have a second method that accepts a compareDelegate to compare different types, but for development purposes I'm sorting a GenericList<int I am recieving stackoverflow areas in different places depending on the list size. I've been staring at and tracing through this code for hours and probably just need a fresh pair of (more experienced)eyes. Definitely wanting to learn why it is broken, not just how to fix it. public void QuickSort() { int i, j, lowPos, highPos, pivot; GenericList<T> leftList = new GenericList<T>(); GenericList<T> rightList = new GenericList<T>(); GenericList<T> tempList = new GenericList<T>(); lowPos = 1; highPos = this.Count; if (lowPos < highPos) { pivot = (lowPos + highPos) / 2; for (i = 1; i <= highPos; i++) { if (this[i].CompareTo(this[pivot]) <= 0) leftList.Add(this[i]); else rightList.Add(this[i]); } leftList.QuickSort(); rightList.QuickSort(); for(i=1;i<=leftList.Count;i++) tempList.Add(leftList[i]); for(i=1;i<=rightList.Count;i++) tempList.Add(rightList[i]); this.items = tempList.items; this.count = tempList.count; } }

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• Program to find the result of primitive recursive functions

  - by alphomega

  I'm writing a program to solve the result of primitive recursive functions: 1 --Basic functions------------------------------ 2 3 --Zero function 4 z :: Int -> Int 5 z = \_ -> 0 6 7 --Successor function 8 s :: Int -> Int 9 s = \x -> (x + 1) 10 11 --Identity/Projection function generator 12 idnm :: Int -> Int -> ([Int] -> Int) 13 idnm n m = \(x:xs) -> ((x:xs) !! (m-1)) 14 15 --Constructors-------------------------------- 16 17 --Composition constructor 18 cn :: ([Int] -> Int) -> [([Int] -> Int)] -> ([Int] -> Int) 19 cn f [] = \(x:xs) -> f 20 cn f (g:gs) = \(x:xs) -> (cn (f (g (x:xs))) gs) these functions and constructors are defined here: http://en.wikipedia.org/wiki/Primitive_recursive_function The issue is with my attempt to create the compositon constructor, cn. When it gets to the base case, f is no longer a partial application, but a result of the function. Yet the function expects a function as the first argument. How can I deal with this problem? Thanks.

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• Recursive code Sorting in VB

  - by Peter

  Ages old question: You have 2 hypothetical eggs, and a 100 story building to drop them from. The goal is to have the least number of guaranteed drops that will ensure you can find what floor the eggs break from the fall. You can only break 2 eggs. Using a 14 drop minimum method, I need help writing code that will allow me to calculate the following: Start with first drop attempt on 14th floor. If egg breaks then drop floors 1-13 to find the floor that causes break. ElseIf egg does not break then move up 13 floors to floor number 27 and drop again. If egg breaks then drop floors 15-26 starting on 15 working up to find the floor egg breaks on. ElseIf egg does not break then move up 12 floors to floor number 39 and drop again. etc. etc. The way this increases is as follows 14+13+12+11+10+9+8+7+6+5+4+3+2+1 So always adding to the previous value, by one less. I have never written a sorting algorithm before, and was curious how I might go about setting this up in a much more efficient way than a mile long of if then statements. My original idea was to store values for the floors in an array, and pull from that, using the index to move up or down and subtract or add to the variables. The most elegant solution would be a recursive function that handled this for any selected floor, 1-100, and ran the math, with an output that shows how many drops were needed in order to find that floor. Maximum is always 14, but some can be done in less.

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• PHP Recursive Function

  - by Tempname

  In my database I have a hierarchical flat table that returns data ordered by ParentID, ObjectID asc I am having a bit of an issue getting this recursive function to work properly. I get the first ParentChildChild but after that I get nothing else. Any help with this is greatly appreciated. Here is my testing code: $objectArr = array(); $objectData = DAOFactory::getTemplateObjectsDAO()->queryByTemplateID(1); for($i = 0; $i < count($objectData); $i++) { if(empty($objectData[$i]->parentID)) { echo $objectData[$i]->objectID; $objectArr[$i] = $objectData[$i]; $objectArr[$i]->children = array(); $objectArr[$i]->children = getChildren($objectData[$i]->objectID, $objectData); } } function getChildren($objectID, $data) { $childArr = array(); foreach($data as $object) { if($object->parentID == $objectID) { $childArr = $object; $childArr->children = array(); $childArr->children = getChildren($object->objectID, $data); } } return $childArr; } new dBug($objectData); This is the output that I am getting: Fullsize Link

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• How do I write recursive anonymous functions?

  - by James T Kirk

  In my continued effort to learn scala, I'm working through 'Scala by example' by Odersky and on the chapter on first class functions, the section on anonymous function avoids a situation of recursive anonymous function. I have a solution that seems to work. I'm curious if there is a better answer out there. From the pdf: Code to showcase higher order functions def sum(f: Int => Int, a: Int, b: Int): Int = if (a > b) 0 else f(a) + sum(f, a + 1, b) def id(x: Int): Int = x def square(x: Int): Int = x * x def powerOfTwo(x: Int): Int = if (x == 0) 1 else 2 * powerOfTwo(x-1) def sumInts(a: Int, b: Int): Int = sum(id, a, b) def sumSquares(a: Int, b: Int): Int = sum(square, a, b) def sumPowersOfTwo(a: Int, b: Int): Int = sum(powerOfTwo, a, b) scala> sumPowersOfTwo(2,3) res0: Int = 12 from the pdf: Code to showcase anonymous functions def sum(f: Int => Int, a: Int, b: Int): Int = if (a > b) 0 else f(a) + sum(f, a + 1, b) def sumInts(a: Int, b: Int): Int = sum((x: Int) => x, a, b) def sumSquares(a: Int, b: Int): Int = sum((x: Int) => x * x, a, b) // no sumPowersOfTwo My code: def sumPowersOfTwo(a: Int, b: Int): Int = sum((x: Int) => { def f(y:Int):Int = if (y==0) 1 else 2 * f(y-1); f(x) }, a, b) scala> sumPowersOfTwo(2,3) res0: Int = 12

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• How to detect the root recursive call?

  - by ahmadabdolkader

  Say we're writing a simple recursive function fib(n) that calculates the nth Fibonacci number. Now, we want the function to print that nth number. As the same function is being called repeatedly, there has to be a condition that allows only the root call to print. The question is: how to write this condition without passing any additional arguments, or using global/static variables. So, we're dealing with something like this: int fib(int n) { if(n <= 0) return 0; int fn = 1; if(n > 2) fn = fib(n-2) + fib(n-1); if(???) cout << fn << endl; return fn; } int main() { fib(5); return 0; } I thought that the root call differs from all children by returning to a different caller, namely the main method in this example. I wanted to know whether it is possible to use this property to write the condition and how. Update: please note that this is a contrived example that only serves to present the idea. This should be clear from the tags. I'm not looking for standard solutions. Thanks.

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• python recursive iteration exceeding limit for tree implementation

  - by user3698027

  I'm implementing a tree dynamically in python. I have defined a class like this... class nodeobject(): def __init__(self,presentnode=None,parent=None): self.currentNode = presentnode self.parentNode = parent self.childs = [] I have a function which gets possible childs for every node from a pool def findchildren(node, childs): # No need to write the whole function on how it gets childs Now I have a recursive function that starts with the head node (no parent) and moves down the chain recursively for every node (base case being the last node having no children) def tree(dad,children): for child in children: childobject = nodeobject(child,dad) dad.childs.append(childobject) newchilds = findchildren(child, children) if len(newchilds) == 0: lastchild = nodeobject(newchilds,childobject) childobject.childs.append(lastchild) loopchild = copy.deepcopy(lastchild) while loopchild.parentNode != None: print "last child" else: tree(childobject,newchilds) The tree formation works for certain number of inputs only. Once the pool gets bigger, it results into "MAXIMUM RECURSION DEPTH EXCEEDED" I have tried setting the recursion limit with set.recursionlimit() and it doesn't work. THe program crashes. I want to implement a stack for recursion, can someone please help, I have gone no where even after trying for a long time ?? Also, is there any other way to fix this other than stack ?

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