Search Results

Search found 765 results on 31 pages for 'discriminated union'.

Page 26/31 | < Previous Page | 22 23 24 25 26 27 28 29 30 31  | Next Page >

  • errors when using c++ bison ---- in the file position.hh

    - by Eric
    firstly I'm not good at English so forgive me. I compile my program with the bison generated files in visual studio and get these errors: ...\position.hh(83): error C2589: '(' : illegal token on right side of '::' ...\position.hh(83): error C2059: syntax error : '::' ...\position.hh(83): error C2589: '(' : illegal token on right side of '::' ...\position.hh(83): error C2059: syntax error : '::' and the corresponding code is: inline void columns (int count = 1) { column = std::max (1u, column + count); } I think the problem is with std::max. If I change std::max to equivalent code then there is problem anymore, but is there a better solution instead of changing the generated code? here is the *.yy file I wrote. // // bison.yy // %skeleton "lalr1.cc" %require "2.4.2" %defines %define parser_class_name "cmd_parser" %locations %debug %error-verbose %code requires { class ParserDriver; } %parse-param { ParserDriver& driver } %lex-param { ParserDriver& driver } %union { struct ast *a; double d; struct symbol *s; struct symlist *sl; int fn; } %code { #include "helper_func.h" #include "ParserDriver.h" std::string error_msg = ""; } %token <d> NUMBER %token <s> NAME %token <fn> FUNC %token EOL %token IF THEN ELSE WHILE DO LET %token SYM_TABLE_OVERFLOW %token UNKNOWN_CHARACTER %nonassoc <fn> CMP %right '=' %left '+' '-' %left '*' '/' %nonassoc '|' UMINUS %type <a> exp stmt list explist %type <sl> symlist %{ extern int yylex(yy::cmd_parser::semantic_type *yylval, yy::cmd_parser::location_type* yylloc); %} %start calclist %% ... grammar rules ...

    Read the article

  • Got a table of people, who I want to link to each other, many-to-many, with the links being bidirect

    - by dflock
    Imagine you live in very simplified example land - and imagine that you've got a table of people in your MySQL database: create table person ( person_id int, name text ) select * from person; +-------------------------------+ | person_id | name | +-------------------------------+ | 1 | Alice | | 2 | Bob | | 3 | Carol | +-------------------------------+ and these people need to collaborate/work together, so you've got a link table which links one person record to another: create table person__person ( person__person_id int, person_id int, other_person_id int ) This setup means that links between people are uni-directional - i.e. Alice can link to Bob, without Bob linking to Alice and, even worse, Alice can link to Bob and Bob can link to Alice at the same time, in two separate link records. As these links represent working relationships, in the real world they're all two-way mutual relationships. The following are all possible in this setup: select * from person__person; +---------------------+-----------+--------------------+ | person__person_id | person_id | other_person_id | +---------------------+-----------+--------------------+ | 1 | 1 | 2 | | 2 | 2 | 1 | | 3 | 2 | 2 | | 4 | 3 | 1 | +---------------------+-----------+--------------------+ For example, with person__person_id = 4 above, when you view Carol's (person_id = 3) profile, you should see a relationship with Alice (person_id = 1) and when you view Alice's profile, you should see a relationship with Carol, even though the link goes the other way. I realize that I can do union and distinct queries and whatnot to present the relationships as mutual in the UI, but is there a better way? I've got a feeling that there is a better way, one where this issue would neatly melt away by setting up the database properly, but I can't see it. Anyone got a better idea?

    Read the article

  • When *not* to use prepared statements?

    - by Ben Blank
    I'm re-engineering a PHP-driven web site which uses a minimal database. The original version used "pseudo-prepared-statements" (PHP functions which did quoting and parameter replacement) to prevent injection attacks and to separate database logic from page logic. It seemed natural to replace these ad-hoc functions with an object which uses PDO and real prepared statements, but after doing my reading on them, I'm not so sure. PDO still seems like a great idea, but one of the primary selling points of prepared statements is being able to reuse them… which I never will. Here's my setup: The statements are all trivially simple. Most are in the form SELECT foo,bar FROM baz WHERE quux = ? ORDER BY bar LIMIT 1. The most complex statement in the lot is simply three such selects joined together with UNION ALLs. Each page hit executes at most one statement and executes it only once. I'm in a hosted environment and therefore leery of slamming their servers by doing any "stress tests" personally. Given that using prepared statements will, at minimum, double the number of database round-trips I'm making, am I better off avoiding them? Can I use PDO::MYSQL_ATTR_DIRECT_QUERY to avoid the overhead of multiple database trips while retaining the benefit of parametrization and injection defense? Or do the binary calls used by the prepared statement API perform well enough compared to executing non-prepared queries that I shouldn't worry about it? EDIT: Thanks for all the good advice, folks. This is one where I wish I could mark more than one answer as "accepted" — lots of different perspectives. Ultimately, though, I have to give rick his due… without his answer I would have blissfully gone off and done the completely Wrong Thing even after following everyone's advice. :-) Emulated prepared statements it is!

    Read the article

  • ISP Config 3 - squirrel login error & how to add an smtp server for sending mails

    - by A Prasetyo
    Hi, Case #1: I have ISPConfig3 running, sending email through telnet server.mydomain.com 25 are possible. Receiving email also possible. BUT!! problem occurs when I try to login to squirrel... I've been awaken for 2 days now and still couldn't figured out why logging in into squirrel always having an error: ERROR: Connection dropped by IMAP server. here is the /var/log/mail.log: Jun 3 00:23:27 server-01 imapd: Connection, ip=[::ffff:127.0.0.1] Jun 3 00:23:27 server-01 imapd: chdir /var/vmail/mydomain.com/info: Permission denied Jun 3 00:23:27 server-01 imapd: [email protected]: Permission denied I did chmod 777 & still doesn't work, only another message appeared Jun 3 00:24:28 server-01 imapd: Connection, ip=[::ffff:127.0.0.1] Jun 3 00:24:28 server-01 imapd: [email protected]: Account's mailbox directory is not owned by the correct uid or gid Try to do telnet to IMAP port telnet mydomain.com 143 Trying 63.105.102.48... Connected to mydomain.com. Escape character is '^]'. OK [CAPABILITY IMAP4rev1 UIDPLUS CHILDREN NAMESPACE THREAD=ORDEREDSUBJECT THREAD=REFERENCES SORT QUOTA IDLE ACL ACL2=UNION STARTTLS] Courier-IMAP ready. Copyright 1998-2008 Double Precision, Inc. See COPYING for distribution information. login [email protected] mypassword login NO Error in IMAP command received by server. and give no result... -_- I checked mysql.sock, I checked username and password in mysql db, everything is correct.. anyone can help? PLEASE?! Case #2: Does anyone know how to set or to view SMTP settings in ISPConfig 3? thank you..

    Read the article

  • SQL Joins Excluding Data

    - by Andrew
    Say I have three tables: Fruit (Table 1) ------ Apple Orange Pear Banana Produce Store A (Table 2 - 2 columns: Fruit for sale => Price) ------------------------- Apple => 1.00 Orange => 1.50 Pear => 2.00 Produce Store B (Table 3 - 2 columns: Fruit for sale => Price) ------------------------ Apple => 1.10 Pear => 2.50 Banana => 1.00 If I would like to write a query with Column 1: the set of fruit offered at Produce Store A UNION Produce Store B, Column 2: Price of the fruit at Produce Store A (or null if that fruit is not offered), Column 3: Price of the fruit at Produce Store B (or null if that fruit is not offered), how would I go about joining the tables? I am facing a similar problem (with more complex tables), and no matter what I try, if the "fruit" is not at "produce store a" but is at "produce store b", it is excluded (since I am joining produce store a first). I have even written a subquery to generate a full list of fruits, then left join Produce Store A, but it is still eliminating the fruits not offered at A. Any Ideas?

    Read the article

  • How to combine a Distance and Keyword SQL query?

    - by Jason
    Hi Folks, I have a tables in my database called "points" and "category". A user will input info into both a location input and a keyword input text box. Then I want to find points in my table where the keyword matches either the "title" field in the points table, or the "category" but are within a certain distance from the user's location. I want to order the results by distance. Here are the 2 queries which btoh work independently: $mysql = "SELECT *, ( 3959 * acos( cos( radians('$search_lat') ) * cos( radians( lat ) ) * cos( radians( longi ) - radians('$search_lng') ) + sin( radians('$search_lat') ) * sin( radians( lat ) ) ) ) AS distance FROM points HAVING distance < '$radius'"; $mysql2 = "SELECT * FROM `points` LEFT JOIN category USING ( category_id ) WHERE (point_title LIKE '%$esc_catsearch%' OR category.title LIKE '%$esc_catsearch%')"; Here is what I tried: $sql_search = sprintf("SELECT *,point_id FROM points WHERE point_title LIKE '%%%s%%' UNION SELECT *, ( 3959 * acos( cos( radians('%s') ) * cos( radians( lat ) ) * cos( radians( longi ) - radians('%s') ) + sin( radians('%s') ) * sin( radians( lat ) ) ) ) AS distance FROM points HAVING distance < '%s' ORDER BY distance LIMIT %d , %d", $esc_catsearch, mysql_real_escape_string($search_lat), mysql_real_escape_string($search_lng), mysql_real_escape_string($search_lat), mysql_real_escape_string($radius), $offset, $rowsPerPage); But it tells me there is no know column "distance". If I remove the "Order By" phrase then it works but I'm still not sure this is giving me the results I want. I also tried the query the other way around with the distance search first but that seems to ignore my keyword. Any thoughts would be much appreciated!

    Read the article

  • how can I speed up insertion of many rows to a table via ADO.NET?

    - by jcollum
    I have a table that has 5 columns: AcctId (int), Address1 (varchar), Address2 (varchar), Person1 (varchar), Person2 (varchar) . I'm generating random data to insert into this table via a C# console application. I've tried doing this random data insert via SQL-Server and decided it was not a good solution -- SQL is not good at random on an each-row basis. Generating the random data -- 975k rows of it -- takes a minimal amount of time. It's in a List of custom objects. I need to take this random data and update many rows in the database with the new random data. I tried updating the rows one at a time, very slow because of the repeated searching of the List object in code. So I think the best approach is to put all the randomized data into a table in the database, then update all the other tables that use this data. I.e. UPDATE t SET t.Address1=d.Address1 FROM Table1 t INNER JOIN RandomizedData d ON d.AcctId = t.Acct_ID. The database is very un-normalized so this Acct data is sprinkled all over the place. I've got no control of the normalization. So, having decided to insert all of the randomized data into a single table, I set out to create insert scripts: USE TheDatabase Insert tmp_RandomizedData SELECT 1,'4392 EIGHTH AVE','','JENNIFER CARTER','BARBARA CARTER' UNION ALL SELECT 2,'2168 MAIN ST','HNGR F','DANIEL HERNANDEZ','SUSAN MARTIN' // etc another 98 times... // FYI, this is not real data! I'm building this INSERT script in batches of 100. It's taking on average 175 ms to run each insert. Does this seem like a long time? It's going to take about 35 mins to run the whole insert. The table doesn't have a primary key or any indexes. I was planning on adding those after all the data in inserted (thinking that that would be faster). Is there a better way to do this?

    Read the article

  • Bi-directional view model syncing with "live" collections and properties (MVVM)

    - by Schneider
    I am getting my knickers in a twist recently about View Models (VM). Just like this guy I have come to the conclusion that the collections I need to expose on my VM typically contain a different type to the collections exposed on my business objects. Hence there must be a bi-directional mapping or transformation between these two types. (Just to complicate things, on my project this data is "Live" such that as soon as you change a property it gets transmitted to other computers) I can just about cope with that concept, using a framework like Truss, although I suspect there will be a nasty surprise somewhere within. Not only must objects be transformed but a synchronization between these two collections is required. (Just to complicate things I can think of cases where the VM collection might be a subset or union of business object collections, not simply a 1:1 synchronization). I can see how to do a one-way "live" sync, using a replicating ObservableCollection or something like CLINQ. The problem then becomes: What is the best way to create/delete items? Bi-directinal sync does not seem to be on the cards - I have found no such examples, and the only class that supports anything remotely like that is the ListCollectionView. Would bi-directional sync even be a sensible way to add back into the business object collection? All the samples I have seen never seem to tackle anything this "complex". So my question is: How do you solve this? Is there some technique to update the model collections from the VM? What is the best general approach to this?

    Read the article

  • sql exception arithmetic overflow?

    - by MyHeadHurts
    In my program the user imports a date and it works whenever the year is in 2011 but if i try a date in 2010 i get this error which is weird [ SqlException (0x80131904): Arithmetic overflow error converting int to data type numeric.] System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection) +1950890 System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) +4846875 System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj) +194 System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj) +2392 System.Data.SqlClient.SqlDataReader.HasMoreRows() +157 System.Data.SqlClient.SqlDataReader.ReadInternal(Boolean setTimeout) +197 System.Data.SqlClient.SqlDataReader.Read() +9 System.Data.Common.DataAdapter.FillLoadDataRow(SchemaMapping mapping) +78 System.Data.Common.DataAdapter.FillFromReader(DataSet dataset, DataTable datatable, String srcTable, DataReaderContainer dataReader, Int32 startRecord, Int32 maxRecords, DataColumn parentChapterColumn, Object parentChapterValue) +164 System.Data.Common.DataAdapter.Fill(DataTable[] dataTables, IDataReader dataReader, Int32 startRecord, Int32 maxRecords) +282 System.Data.Common.LoadAdapter.FillFromReader(DataTable[] dataTables, IDataReader dataReader, Int32 startRecord, Int32 maxRecords) +19 System.Data.DataTable.Load(IDataReader reader, LoadOption loadOption, FillErrorEventHandler errorHandler) +222 System.Data.DataTable.Load(IDataReader reader) +14 ( @YearToGet int, @current datetime, @y int, @search datetime ) AS SET @YearToGet = 2006; WITH Years AS ( SELECT DATEPART(year, GETDATE()) [Year] UNION ALL SELECT [Year]-1 FROM Years WHERE [Year]>@YearToGet ), q_00 as ( select DIVISION , DYYYY , sum(PARTY) as asofPAX , sum(InsAmount) as asofSales from dbo.B101BookingsDetails INNER JOIN Years ON B101BookingsDetails.DYYYY = Years.Year where Booked <= CONVERT(int, DateAdd(year, (Years.Year - @y), @search)) and DYYYY = Years.Year group by DIVISION, DYYYY, years.year having DYYYY = years.year ), q_01 as ( select DIVISION , DYYYY , sum(PARTY) as YEPAX , sum(InsAmount) as YESales from dbo.B101BookingsDetails INNER JOIN Years ON B101BookingsDetails.DYYYY = Years.Year group by DIVISION, DYYYY , years.year having DYYYY = years.year ), q_02 as ( select DIVISION , DYYYY , sum(PARTY) as CurrentPAX , sum(InsAmount) as CurrentSales from dbo.B101BookingsDetails INNER JOIN Years ON B101BookingsDetails.DYYYY = Years.Year where Booked <= CONVERT(int,@current) and DYYYY = (year( getdate() )) group by DIVISION, DYYYY ) select a.DIVISION , a.DYYYY , asofPAX , asofSales , YEPAX , YESales , CurrentPAX , CurrentSales ,asofsales/ ISNULL(NULLIF(yesales,0),1) as percentsales, CAST((asofpax) AS DECIMAL(5,1))/yepax as percentpax from q_00 as a join q_01 as b on (b.DIVISION = a.DIVISION and b.DYYYY = a.DYYYY) join q_02 as c on (b.DIVISION = c.DIVISION) JOIN Years as d on (b.dyyyy = d.year) where A.DYYYY <> (year( getdate() )) order by a.DIVISION, a.DYYYY ;

    Read the article

  • Excel and SQL, order by help

    - by perlnoob
    Im stuck in Excel 2007, running a query, it worked until I wanted to add a 2nd row containing "field 2". Select "Site Updates"."Posted By", "Site Uploaded"."Site Upload Date" From site_info.dbo."Site Updates" Where ("Site Updates"."Posted By") AND "Site Uploaded"."Site Upload Date">={ts '2010-05-01 00:00:00'}), ("Site Location"='Chicago') Union all Select "Site Updates"."Posted By", "Site Uploaded"."Site Upload Date" From site_info.dbo."Site Updates" Where ("Site Updates"."Posted By") AND "Site Uploaded"."Site Upload Date">={ts '2010-05-01 00:00:00'}), ("Site Location"='Denver') Order By "Site Location" ASC; Basically I want 2 different cells for the locations, example name - Chicago - denver user1 - 100 - 20 user2 - 34 - 1002 Right now for some odd reason, its combining it like: name - chicago user1 - 120 user2 - 1036 Please note updating to 2010 beta is not a viable option for me at this point. Any and all input that will help me is greatly apprecaited. I have read over http://www.techonthenet.com/sql/order_by.php however its not gotten me very far in this question. If you have another SQL resource you recomend for people trying to get their feet wet, I'd greatly apprecaite it. If it helps all the info is on the same table.

    Read the article

  • Possible to rank partial matches in Postgres full text search?

    - by Joe
    I'm trying to calculate a ts_rank for a full-text match where some of the terms in the query may not be in the ts_vector against which it is being matched. I would like the rank to be higher in a match where more words match. Seems pretty simple? Because not all of the terms have to match, I have to | the operands, to give a query such as to_tsquery('one|two|three') (if it was &, all would have to match). The problem is, the rank value seems to be the same no matter how many words match. In other words, it's maxing rather than multiplying the clauses. select ts_rank('one two three'::tsvector, to_tsquery('one')); gives 0.0607927. select ts_rank('one two three'::tsvector, to_tsquery('one|two|three|four')); gives the expected lower value of 0.0455945 because 'four' is not the vector. But select ts_rank('one two three'::tsvector, to_tsquery('one|two')); gives 0.0607927 and likewise select ts_rank('one two three'::tsvector, to_tsquery('one|two|three')); gives 0.0607927 I would like the result of ts_rank to be higher if more terms match. Possible? To counter one possible response: I cannot calculate all possible subsequences of the search query as intersections and then union them all in a query because I am going to be working with large queries. I'm sure there are plenty of arguments against this anyway! Edit: I'm aware of ts_rank_cd but it does not solve the above problem.

    Read the article

  • libpcap read packet size

    - by spicyramen
    I started to write an application which will read RTP/H.264 video packets from an existing .pcap file, I need to read the packet size. I tried to use packet-len or header-len, but it never displays the right number of bytes for packets (I'm using wireshark to verify packet size - under Length column). How to do it? This is part of my code: while (packet = pcap_next(handle,&header)) { u_char *pkt_ptr = (u_char *)packet; struct ip *ip_hdr = (struct ip *)pkt_ptr; //point to an IP header structure struct pcap_pkthdr *pkt_hdr =(struct pcap_pkthdr *)packet; unsigned int packet_length = pkt_hdr->len; unsigned int ip_length = ntohs(ip_hdr->ip_len); printf("Packet # %i IP Header length: %d bytes, Packet length: %d bytes\n",pkt_counter,ip_length,packet_length); Packet # 0 IP Header length: 180 bytes, Packet length: 104857664 bytes Packet # 1 IP Header length: 52 bytes, Packet length: 104857600 bytes Packet # 2 IP Header length: 100 bytes, Packet length: 104857600 bytes Packet # 3 IP Header length: 100 bytes, Packet length: 104857664 bytes Packet # 4 IP Header length: 52 bytes, Packet length: 104857600 bytes Packet # 5 IP Header length: 100 bytes, Packet length: 104857600 bytes Another option I tried is to use: pkt_ptr- I get: read_pcapfile.c:67:43: error: request for member ‘len’ in something not a structure or union

    Read the article

  • Would this method work to scale out SQL queries?

    - by David
    I have a database containing a single huge table. At the moment a query can take anything from 10 to 20 minutes and I need that to go down to 10 seconds. I have spent months trying different products like GridSQL. GridSQL works fine, but is using its own parser which does not have all the needed features. I have also optimized my database in various ways without getting the speedup I need. I have a theory on how one could scale out queries, meaning that I utilize several nodes to run a single query in parallel. The idea is to take an incoming SQL query and simply run it exactly like it is on all the nodes. When the results are returned to a coordinator node, the same query is run on the union of the resultsets. I realize that an aggregate function like average need to be rewritten into a count and sum to the nodes and that the coordinator divides the sum of the sums with the sum of the counts to get the average. What kinds of problems could not easily be solved using this model. I believe one issue would be the count distinct function. Edit: I am getting so many nice suggestions, but none have addressed the method.

    Read the article

  • How do tools like Hiphop for PHP deal with heterogenous arrays?

    - by Derek Thurn
    I think HipHop for PHP is an interesting tool. It essentially converts PHP code into C++ code. Cross compiling in this manner seems like a great idea, but I have to wonder, how do they overcome the fundamental differences between the two type systems? One specific example of my general question is heterogeneous data structures. Statically typed languages don't tend to let you put arbitrary types into an array or other container because they need to be able to figure out the types on the other end. If I have a PHP array like this: $mixedBag = array("cat", 42, 8.5, false); How can this be represented in C++ code? One option would be to use void pointers (or the superior version, boost::any), but then you need to cast when you take stuff back out of the array... and I'm not at all convinced that the type inferencer can always figure out what to cast to at the other end. A better option, perhaps, would be something more like a union (or boost::variant), but then you need to enumerate all possible types at compile time... maybe possible, but certainly messy since arrays can contain arbitrarily complex entities. Does anyone know how HipHop and similar tools which go from a dynamic typing discipline to a static discipline handle these types of problems?

    Read the article

  • Can't get this SPARQL query to work

    - by Jason
    Okay, I'm just learning to use SPARQL to query data from dbpedia.org and I'm using dbpedia's http://dbpedia.org/snorql/ to run my queries in. I am trying to get a list of MusicalArtists based on searching for the same string over three fields like so: SELECT ?subject ?artistRdfsLabel ?artistFoafName ?artistDbpedia2Name WHERE { ?subject rdf:type <http://dbpedia.org/ontology/MusicalArtist> . OPTIONAL { ?subject rdfs:label ?artistRdfsLabel . } OPTIONAL { ?subject foaf:name ?artistFoafName . } OPTIONAL { ?subject dbpedia2:name ?artistDbpedia2Name . } FILTER ( str(?artistRdfsLabel) = "Stevie Nicks" || str(?artistFoafName) = "Stevie Nicks" || str(?artistDbpedia2Name) = "Stevie Nicks" ) } LIMIT 10 This works because "Stevie Nicks" has all three fields (rdfs:label, foaf:name, dbpedia2:name). But when I try to query by another MusicalArtist that doesn't have all three ("Depeche Mode" for example) I get no results. I have tried various things like BIND(COALESCE(?field,...,...) AS ?artistName) to filter by ?artistName and I also tried UNION but nothing seems to work. Can someone point out the error of my SPARQL ways? :) Thanks! Jason

    Read the article

  • How do I improve my performance with this singly linked list struct within my program?

    - by Jesus
    Hey guys, I have a program that does operations of sets of strings. We have to implement functions such as addition and subtraction of two sets of strings. We are suppose to get it down to the point where performance if of O(N+M), where N,M are sets of strings. Right now, I believe my performance is at O(N*M), since I for each element of N, I go through every element of M. I'm particularly focused on getting the subtraction to the proper performance, as if I can get that down to proper performance, I believe I can carry that knowledge over to the rest of things I have to implement. The '-' operator is suppose to work like this, for example. Declare set1 to be an empty set. Declare set2 to be a set with { a b c } elements Declare set3 to be a set with ( b c d } elements set1 = set2 - set3 And now set1 is suppose to equal { a }. So basically, just remove any element from set3, that is also in set2. For the addition implementation (overloaded '+' operator), I also do the sorting of the strings (since we have to). All the functions work right now btw. So I was wondering if anyone could a) Confirm that currently I'm doing O(N*M) performance b) Give me some ideas/implementations on how to improve the performance to O(N+M) Note: I cannot add any member variables or functions to the class strSet or to the node structure. The implementation of the main program isn't very important, but I will post the code for my class definition and the implementation of the member functions: strSet2.h (Implementation of my class and struct) // Class to implement sets of strings // Implements operators for union, intersection, subtraction, // etc. for sets of strings // V1.1 15 Feb 2011 Added guard (#ifndef), deleted using namespace RCH #ifndef _STRSET_ #define _STRSET_ #include <iostream> #include <vector> #include <string> // Deleted: using namespace std; 15 Feb 2011 RCH struct node { std::string s1; node * next; }; class strSet { private: node * first; public: strSet (); // Create empty set strSet (std::string s); // Create singleton set strSet (const strSet &copy); // Copy constructor ~strSet (); // Destructor int SIZE() const; bool isMember (std::string s) const; strSet operator + (const strSet& rtSide); // Union strSet operator - (const strSet& rtSide); // Set subtraction strSet& operator = (const strSet& rtSide); // Assignment }; // End of strSet class #endif // _STRSET_ strSet2.cpp (implementation of member functions) #include <iostream> #include <vector> #include <string> #include "strset2.h" using namespace std; strSet::strSet() { first = NULL; } strSet::strSet(string s) { node *temp; temp = new node; temp->s1 = s; temp->next = NULL; first = temp; } strSet::strSet(const strSet& copy) { if(copy.first == NULL) { first = NULL; } else { node *n = copy.first; node *prev = NULL; while (n) { node *newNode = new node; newNode->s1 = n->s1; newNode->next = NULL; if (prev) { prev->next = newNode; } else { first = newNode; } prev = newNode; n = n->next; } } } strSet::~strSet() { if(first != NULL) { while(first->next != NULL) { node *nextNode = first->next; first->next = nextNode->next; delete nextNode; } } } int strSet::SIZE() const { int size = 0; node *temp = first; while(temp!=NULL) { size++; temp=temp->next; } return size; } bool strSet::isMember(string s) const { node *temp = first; while(temp != NULL) { if(temp->s1 == s) { return true; } temp = temp->next; } return false; } strSet strSet::operator + (const strSet& rtSide) { strSet newSet; newSet = *this; node *temp = rtSide.first; while(temp != NULL) { string newEle = temp->s1; if(!isMember(newEle)) { if(newSet.first==NULL) { node *newNode; newNode = new node; newNode->s1 = newEle; newNode->next = NULL; newSet.first = newNode; } else if(newSet.SIZE() == 1) { if(newEle < newSet.first->s1) { node *tempNext = newSet.first; node *newNode; newNode = new node; newNode->s1 = newEle; newNode->next = tempNext; newSet.first = newNode; } else { node *newNode; newNode = new node; newNode->s1 = newEle; newNode->next = NULL; newSet.first->next = newNode; } } else { node *prev = NULL; node *curr = newSet.first; while(curr != NULL) { if(newEle < curr->s1) { if(prev == NULL) { node *newNode; newNode = new node; newNode->s1 = newEle; newNode->next = curr; newSet.first = newNode; break; } else { node *newNode; newNode = new node; newNode->s1 = newEle; newNode->next = curr; prev->next = newNode; break; } } if(curr->next == NULL) { node *newNode; newNode = new node; newNode->s1 = newEle; newNode->next = NULL; curr->next = newNode; break; } prev = curr; curr = curr->next; } } } temp = temp->next; } return newSet; } strSet strSet::operator - (const strSet& rtSide) { strSet newSet; newSet = *this; node *temp = rtSide.first; while(temp != NULL) { string element = temp->s1; node *prev = NULL; node *curr = newSet.first; while(curr != NULL) { if( element < curr->s1 ) break; if( curr->s1 == element ) { if( prev == NULL) { node *duplicate = curr; newSet.first = newSet.first->next; delete duplicate; break; } else { node *duplicate = curr; prev->next = curr->next; delete duplicate; break; } } prev = curr; curr = curr->next; } temp = temp->next; } return newSet; } strSet& strSet::operator = (const strSet& rtSide) { if(this != &rtSide) { if(first != NULL) { while(first->next != NULL) { node *nextNode = first->next; first->next = nextNode->next; delete nextNode; } } if(rtSide.first == NULL) { first = NULL; } else { node *n = rtSide.first; node *prev = NULL; while (n) { node *newNode = new node; newNode->s1 = n->s1; newNode->next = NULL; if (prev) { prev->next = newNode; } else { first = newNode; } prev = newNode; n = n->next; } } } return *this; }

    Read the article

  • Added buttons, webview, added outlets, but can't play with them in the code...

    - by Tom
    Hi! I made a toolbar with two buttons on it. I then created two outlets in my class controller. Then I hooked the the controller to the buttons and selected the outlets. Finally I rewritten the class files (that added: IBOutlet id next; IBOutlet id previous; to my .h file). So now, everything looks okay. But then I try somewhere in the code to change the state of one of my button like this: next.enabled = YES; I tried with self. too but unfortunately I receive this error message: error: request for member 'enabled' in something not a structure or union Do you have any idea of what's happening there? And yes I have: #import <UIKit/UIKit.h> :) Using: [next setEnabled:YES]; gives me no error but still doesn't work... And finally, for documenting purposes here's the whole method: - (void)viewDidLoad { [super viewDidLoad]; if (!self.currentLevel) { self.currentLevel = @"1"; } NSArray *etape = [self.etapes objectForKey:self.currentLevel]; if ([etape count] > 0) { self.navigationItem.title = [etape objectAtIndex:1]; if ([etape count] > 1) { [next setEnabled:YES]; } } else { self.navigationItem.title = @"Aucune étape"; } } When I do: NSLog(@"%@", [next class]); It returns (null) ... I guess it is supposed to be UIBarButtonItem... It seems that it is impossible to play with any outlets even if I don't receive any errors while playing with them...

    Read the article

  • Advantage Database Server ORDER BY behaviour

    - by ie
    I'm using ADS v10 beta. I'm trying to numerate ordered resultset. 1) ORDER BY in nested queries. I need to use nested SELECT for some calculations: SELECT Name, Value, ROWNUM() FROM (SELECT * FROM MainTable WHERE Value > 0 ORDER BY Value) a And I'm getting Expected lexical element not found: ) There was a problem parsing the table names after the FROM keyword in your SELECT statement. Everything is working well when the ORDER BY is removed. Although, I found the sample in the Help, it looks like my query (more complex, indeed): SELECT * FROM (SELECT TOP 10 empid, fullname FROM branch1 ORDER BY empid) a UNION SELECT empid, fullname FROM branch2 ORDER BY empid 2) ORDER BY + ROWNUM(). I used the nested query in the example above, to numerate ordered rows. Is there are any chance to avoid nested query? In the SQL Server I can do something like this: SELECT Name, Value, ROW_NUMBER() OVER(ORDER BY Value) FROM MainTable WHERE Value > 1 ORDER BY Value Please advice. Thanks.

    Read the article

  • Compile time float packing/punning

    - by detly
    I'm writing C for the PIC32MX, compiled with Microchip's PIC32 C compiler (based on GCC 3.4). My problem is this: I have some reprogrammable numeric data that is stored either on EEPROM or in the program flash of the chip. This means that when I want to store a float, I have to do some type punning: typedef union { int intval; float floatval; } IntFloat; unsigned int float_as_int(float fval) { IntFloat intf; intf.floatval = fval; return intf.intval; } // Stores an int of data in whatever storage we're using void StoreInt(unsigned int data, unsigned int address); void StoreFPVal(float data, unsigned int address) { StoreInt(float_as_int(data), address); } I also include default values as an array of compile time constants. For (unsigned) integer values this is trivial, I just use the integer literal. For floats, though, I have to use this Python snippet to convert them to their word representation to include them in the array: import struct hex(struct.unpack("I", struct.pack("f", float_value))[0]) ...and so my array of defaults has these indecipherable values like: const unsigned int DEFAULTS[] = { 0x00000001, // Some default integer value, 1 0x3C83126F, // Some default float value, 0.005 } (These actually take the form of X macro constructs, but that doesn't make a difference here.) Commenting is nice, but is there a better way? It's be great to be able to do something like: const unsigned int DEFAULTS[] = { 0x00000001, // Some default integer value, 1 COMPILE_TIME_CONVERT(0.005), // Some default float value, 0.005 } ...but I'm completely at a loss, and I don't even know if such a thing is possible. Notes Obviously "no, it isn't possible" is an acceptable answer if true. I'm not overly concerned about portability, so implementation defined behaviour is fine, undefined behaviour is not (I have the IDB appendix sitting in front of me). As fas as I'm aware, this needs to be a compile time conversion, since DEFAULTS is in the global scope. Please correct me if I'm wrong about this.

    Read the article

  • Force a view change from a button when using UITabBarController

    - by user342197
    Hello - When using a UITabBarController, when the user enters some data on View1 and presses a button, I need to perform some calculations and present the results on View2. I have an AppDelegate, View1Controller, View2Controller, and View3Controller (View3 is a basically static view). My AppDelgate declares UITabBarController *rootController; On View1, I have the calculations being performed in an IBAction for buttonPressed; however, I can't seem to force the view to switch to View2 programmatically. I have done a lot of searching for similar problems, and think I should be doing something like "self.rootController.selectedIndex = 1"; however,when I do this from within buttonPressed on my View1Controller, I get an error "request for member rootController in something not in a structure or union". I think I'm missing something basic here... probably need do do something with my AppDelegate, but I'm banging my head against the wall. Can anyone provide some guidance in this situation...like key things I should do in View1Controller header and implementation with reference to my AppDelgate? Thank you!

    Read the article

  • problem in fetching data from several tables in one query

    - by Mac Taylor
    hey guys in an attempt to union my querries into one query to database , now im in need of geting username of first poster and last poster of a topic in my forums here is my code to do as i told :: $result = $db->sql_query("SELECT t.*,p.*,u.* SUM(t.topic_approved='1') AS Amount_Of_Topics, SUM(p.post_approved ='1') AS Amount_Of_Posts FROM bb3topics t, bb3posts p, bb3users u GROUP BY t.topic_last_post_id ORDER BY t.topic_last_post_id DESC LIMIT 10 " ); while( $row = $db->sql_fetchrow($result) ) { $Amount_Of_Topics = $row['Amount_Of_Topics']; $Amount_Of_Posts = $row['Amount_Of_Posts']; $Amount_Of_Topic_Replies = $Amount_Of_Topic_Replies + $row['topic_replies']; $Amount_Of_Topic_Views = $Amount_Of_Topic_Views + $row['topic_views']; $topic_id = $row['topic_id']; $forum_id = $row['forum_id']; $topic_last_post_id = $row['topic_last_post_id']; $topic_title = $row['topic_title']; $topic_poster = $row['topic_poster']; $topic_views = $row['topic_views']; $topic_replies = $row['topic_replies']; $topic_moved_id = $row['topic_moved_id']; $topic_time = $row['topic_time']; $result2 = $db->sql_query( "SELECT topic_id, poster_id, post_time FROM bb3posts where post_id = '$topic_last_post_id'" ); list( $topic_id, $poster_id, $post_time ) = $db->sql_fetchrow( $result2 ); $result3 = $db->sql_query( "SELECT username, user_id FROM bb3users where user_id='$poster_id'" ); list( $uname, $uid ) = $db->sql_fetchrow( $result3 ); $LastPoster = "$uname"; $result4 = $db->sql_query( "SELECT username, user_id FROM bb3users where user_id='$topic_poster'" ); list( $uname, $uid ) = $db->sql_fetchrow( $result4 ); $OrigPoster = "$uname"; now i need to query all this together not in separated ones i tried using left join but didn't worked what mysql conjunction should i use ?!

    Read the article

  • Array of templated structs

    - by Jakub Mertlik
    I have structs templated by int derived from a Base struct. struct Base { int i; double d; }; template< int N > struct Derv : base { static const int mN = N; }; I need to make an array of Derv< N where N can vary for each struct in that array. I know C/C++ does not allow arrays of objects of different types, but is there a way around this? I was thinking of separating the type information somehow (hints like pointers to Base struct or usage of union spring to my mind, but with all of these I don't know how to store the type information of each array element for usage DURING COMPILE TIME). As you can see, the memory pattern of each Derv< N is the same. I need to access the type of each array element for template specialization later in my code. The general aim of this all is to have a compile-time dispatch mechanism without the need to do a runtime "type switch" somewhere in the code. Thank you.

    Read the article

  • Group / User based security. Table / SQL question

    - by Brett
    Hi, I'm setting up a group / user based security system. I have 4 tables as follows: user groups group_user_mappings acl where acl is the mapping between an item_id and either a group or a user. The way I've done the acl table, I have 3 columns of note (actually 4th one as an auto-id, but that is irrelevant) col 1 item_id (item to access) col 3 user_id (user that is allowed to access) col 3 group_id (group that is allowed to access) So for example item1, peter, , item2, , group1 item3, jane, , so either the acl will give access to a user or a group. Any one line in the ACL table with either have an item - user mapping, or an item group. If I want to have a query that returns all objects a user has access to, I think I need to have a SQL query with a UNION, because I need 2 separate queries that join like.. item - acl - group - user AND item - acl - user This I guess will work OK. Is this how its normally done? Am I doing this the right way? Seems a little messy. I was thinking I could get around it by creating a single user group for each person, so I only ever deal with groups in my SQL, but this seems a little messy as well..

    Read the article

  • How can I pass a const array or a variable array to a function in C?

    - by CSharperWithJava
    I have a simple function Bar that uses a set of values from a data set that is passed in in the form of an Array of data structures. The data can come from two sources: a constant initialized array of default values, or a dynamically updated cache. The calling function determines which data is used and should be passed to Bar. Bar doesn't need to edit any of the data and in fact should never do so. How should I declare Bar's data parameter so that I can provide data from either set? union Foo { long _long; int _int; } static const Foo DEFAULTS[8] = {1,10,100,1000,10000,100000,1000000,10000000}; static Foo Cache[8] = {0}; void Bar(Foo* dataSet, int len);//example function prototype Note, this is C, NOT C++ if that makes a difference; Edit Oh, one more thing. When I use the example prototype I get a type qualifier mismatch warning, (because I'm passing a mutable reference to a const array?). What do I have to change for that?

    Read the article

  • How to efficiently compare the sign of two floating-point values while handling negative zeros

    - by François Beaune
    Given two floating-point numbers, I'm looking for an efficient way to check if they have the same sign, given that if any of the two values is zero (+0.0 or -0.0), they should be considered to have the same sign. For instance, SameSign(1.0, 2.0) should return true SameSign(-1.0, -2.0) should return true SameSign(-1.0, 2.0) should return false SameSign(0.0, 1.0) should return true SameSign(0.0, -1.0) should return true SameSign(-0.0, 1.0) should return true SameSign(-0.0, -1.0) should return true A naive but correct implementation of SameSign in C++ would be: bool SameSign(float a, float b) { if (fabs(a) == 0.0f || fabs(b) == 0.0f) return true; return (a >= 0.0f) == (b >= 0.0f); } Assuming the IEEE floating-point model, here's a variant of SameSign that compiles to branchless code (at least with with Visual C++ 2008): bool SameSign(float a, float b) { int ia = binary_cast<int>(a); int ib = binary_cast<int>(b); int az = (ia & 0x7FFFFFFF) == 0; int bz = (ib & 0x7FFFFFFF) == 0; int ab = (ia ^ ib) >= 0; return (az | bz | ab) != 0; } with binary_cast defined as follow: template <typename Target, typename Source> inline Target binary_cast(Source s) { union { Source m_source; Target m_target; } u; u.m_source = s; return u.m_target; } I'm looking for two things: A faster, more efficient implementation of SameSign, using bit tricks, FPU tricks or even SSE intrinsics. An efficient extension of SameSign to three values.

    Read the article

< Previous Page | 22 23 24 25 26 27 28 29 30 31  | Next Page >