Search Results

Search found 36715 results on 1469 pages for 'boost string'.

Page 17/1469 | < Previous Page | 13 14 15 16 17 18 19 20 21 22 23 24  | Next Page >

  • Increasing time resolution of BOOST::progress timer

    - by feelfree
    BOOST::progress_timer is a very useful class to measure the running time of a function. However, the default implementation of progress_timer is not accurate enough and a possible way of increasing time resolution is to reconstruct a new class as the following codes show: #include <boost/progress.hpp> #include <boost/static_assert.hpp> template<int N=2> class new_progress_timer:public boost::timer { public: new_progress_timer(std::ostream &os=std::cout):m_os(os) { BOOST_STATIC_ASSERT(N>=0 &&N<=10); } ~new_progress_timer(void) { try { std::istream::fmtflags old_flags = m_os.setf(std::istream::fixed,std::istream::floatfield); std::streamsize old_prec = m_os.precision(N); m_os<<elapsed()<<"s\n" <<std::endl; m_os.flags(old_flags); m_os.precison(old_prec); } catch(...) { } } private: std::ostream &m_os; }; However, when I compile the codes with VC10, the following error appear: 'precison' : is not a member of 'std::basic_ostream<_Elem,_Traits>' Any ideas? Thanks.

    Read the article

  • C++ member template for boost ptr_vector

    - by Ivan
    Hi there, I'm trying to write a container class using boost::ptr_vector. Inside the ptr_vector I would like to include different classes. I'm trying to achieve that using static templates, but so far I'm not able to do that. For example, the container class is class model { private: boost::ptr_vector<elem_type> elements; public: void insert_element(elem_type *a) { element_list.push_back(a); } }; and what I'm trying to achieve is be able to use different elem_type classes. The code below doesn't satisfy my requirements: template <typename T>class model { private: boost::ptr_vector<T> elements; public: void insert_element(T *a) { element_list.push_back(a); } }; because when I initialize the container class I can only use one class as template: model <elem_type_1> model_thing; model_thing.insert_element(new elem_type_1) but not elem_type_2: model_thing.insert_element(new elem_type_2)//error, of course It is possible to do something like using templates only on the member? class model { private: template <typename T> boost::ptr_vector<T> elements; public: void insert_element(T *a) { element_list.push_back(a); } }; //wrong So I can call the insert_element on the specific class that I want to insert? Note that I do not want to use virtual members. Thanks!

    Read the article

  • NameValueCollection vs Dictionary<string,string>

    - by frankadelic
    Any reason I should use Dictionary<string,string instead of NameValueCollection? (in C# / .NET Framework) Option 1, using NameValueCollection: //enter values: NameValueCollection nvc = new NameValueCollection() { {"key1", "value1"}, {"key2", "value2"}, {"key3", "value3"} }; // retrieve values: foreach(string key in nvc.AllKeys) { string value = nvc[key]; // do something } Option 2, using Dictionary<string,string... //enter values: Dictionary<string, string> dict = new Dictionary<string, string>() { {"key1", "value1"}, {"key2", "value2"}, {"key3", "value3"} }; // retrieve values: foreach (KeyValuePair<string, string> kvp in dict) { string key = kvp.Key; string val = kvp.Value; // do something } For these use cases, is there any advantage to use one versus the other? Any difference in performance, memory use, sort order, etc.?

    Read the article

  • How to have a function with a nullable string parameter in Go?

    - by yuku
    I'm used to Java's String where we can pass null rather than "" for special meanings, such as use a default value. In Go, string is a primitive type, so I cannot pass nil (null) to a parameter that requires a string. I could write the function using pointer type, like this: func f(s *string) so caller can call that function either as f(nil) or // not so elegant temp := "hello"; f(&temp) but the following is unfortunately not allowed: // elegant but disallowed f(&"hello"); What is the best way to have a parameter that receives either a string or nil?

    Read the article

  • BOOST.IOstreams: trouble to write to bzip2.

    - by Arman
    Hello I am would like to store my data in to bzip2 file using Boost.IOstreams. void test_bzip() { namespace BI = boost::iostreams; { string fname="test.bz2"; { BI::filtering_stream<BI::bidirectional> my_filter; my_filter.push(BI::combine(BI::bzip2_decompressor(), BI::bzip2_compressor())) ; my_filter.push(std::fstream(fname.c_str(), std::ios::binary|std::ios::out)) ; my_filter << "test" ; }//when my_filter is destroyed it is trowing an assertion. } }; What I am doing wrong? I am using boost 1.42.0. kind regards Arman.

    Read the article

  • Concatenate boost::dynamic_bitset or std::bitset

    - by MOnsDaR
    Hey, what is the best way to concatenate 2 bitsets? For example i've got boost::dynamic_bitset<> test1( std::string("1111") ); boost::dynamic_bitset<> test2( std::string("00") ); they should be concatenated into a thrid Bitset test3 which then holds 111100 Solutions should use boost::dynamic_bitset. If the solution works with std::bitset, it would be nice too. There should be a focus on performance when concatenating the bits.

    Read the article

  • Help with C++ Boost::regex

    - by Youssef
    Hello everybody, I'm trying to get all words inside a string using Boost::regex in C++. Here's my input : "Hello there | network - bla bla hoho" using this code : regex rgx("[a-z]+",boost::regex::perl|boost::regex::icase); regex_search(input, result, rgx); for(unsigned int j=0; j I only get the first word "Hello".. whats wrong with my code ? result.size() returns 1. thank you.

    Read the article

  • Boost.Python tutorial in Ubuntu 10.04

    - by Doughy
    I downloaded the latest version of Boost and I'm trying to get the Boost.python tutorial up and running on Ubuntu 10.04: http://www.boost.org/doc/libs/1_43_0/libs/python/doc/tutorial/doc/html/python/hello.html I navigated to the correct directory, ran "bjam" and it compiled using default settings. I did not yet create a bjam config file. The compilation appears to have worked, but now I have no idea how to include the files in my python script. When I try to run the python hello world script, it gives me this error: Traceback (most recent call last): File "./hello.py", line 6, in <module> import hello_ext ImportError: libboost_python.so.1.43.0: cannot open shared object file: No such file or directory Anyone know what is going on?

    Read the article

  • Using boost unordered map

    - by Amrish
    Guys, I am using dynamic programming approach to solve a problem. Here is a brief overview of the approach Each value generated is identified using 25 unique keys. I use the boost::hash_combine to generate the seed for the hash table using these 25 keys. I store the values in a hash table declared as boost::unordered_map<Key_Object, Data_Object, HashFunction> hashState; I did a time profiling on my algorithm and found that nearly 95% of the run time is spent towards retrieving/inserting data into the hash table. These were the details of my hash table hashState.size() 1880 hashState.load_factor() 0.610588 hashState.bucket_count() 3079 hashState.max_size() 805306456 hashState.max_load_factor() 1 hashState.max_bucket_count() 805306457 I have the following two questions Is there anything which I can do to improve the performance of the Hash Table's insert/retrieve operations? C++ STL has hash_multimap which would also suit my requirement. How does boost libraries unordered_map compare with hash_multimap in terms of insert/retrieve performance.

    Read the article

  • VC++ 2010 wants to link boost libararies i didn't even specify

    - by Philipp
    Hi there, I'm trying to build my application with MSVC 2010 instead of GCC. With GCC everything works fine. My app uses boost_system and boost_thread libraries. I built boost with VC2010 in "system" layout, that means the libraries are named just libboost_system.lib (and not libboost_system_compiler_threading_version_wtf_snafu.lib) The libs reside in C:\Boost\lib, the Makefile specifies LFLAGS = /NOLOGO /INCREMENTAL:NO /SUBSYSTEM:CONSOLE LIBS = /LIBPATH:C:/Boost/lib libboost_system.lib libboost_thread.lib Ws2_32.lib when invoking nmake it compiles, but when trying to link it quits with LINK : fatal error LNK1104: cannot open file 'libboost_date_time-vc100-mt-1_43.lib I mean seriously, WTF? I told it to link libboost_systen.lib and libboost_thread.lib how come it tries to link libboost_data_time and why does it assume I built the libs in "tagged" layout?? How can I stop MSVC trying to be smart and guess what I might have wanted to link? Thanks, Philipp

    Read the article

  • typedef boost::shared_ptr<MyJob> Ptr; or #define Ptr boost::shared_ptr

    - by danio
    I've just started wrking on a new codebase where each class contains a shared_ptr typedef (similar to this) like: typedef boost::shared_ptr<MyClass> Ptr; Is the only purpose to save typing boost::shared_ptr? If that is the case why not do #define Ptr boost::shared_ptr in one common header? Then you can do: Ptr<MyClass> myClass(new MyClass); which is no more typing than MyClass::Ptr myClass(new MyClass); and saves the Ptr definition in each class.

    Read the article

  • How to use boost::fusion::transform on heterogeneous containers?

    - by Kyle
    Boost.org's example given for fusion::transform is as follows: struct triple { typedef int result_type; int operator()(int t) const { return t * 3; }; }; // ... assert(transform(make_vector(1,2,3), triple()) == make_vector(3,6,9)); Yet I'm not "getting it." The vector in their example contains elements all of the same type, but a major point of using fusion is containers of heterogeneous types. What if they had used make_vector(1, 'a', "howdy") instead? int operator()(int t) would need to become template<typename T> T& operator()(T& const t) But how would I write the result_type? template<typename T> typedef T& result_type certainly isn't valid syntax, and it wouldn't make sense even if it was, because it's not tied to the function.

    Read the article

  • Simple and efficient distribution of C++/Boost source code (amalgamation)

    - by Arrieta
    Hello: My job mostly consists of engineering analysis, but I find myself distributing code more and more frequently among my colleagues. A big pain is that not every user is proficient in the intricacies of compiling source code, and I cannot distribute executables. I've been working with C++ using Boost, and the problem is that I cannot request every sysadmin of every network to install the libraries. Instead, I want to distribute a single source file (or as few as possible) so that the user can g++ source.c -o program. So, the question is: can you pack the Boost libraries with your code, and end up with a single file? I am talking about the Boost libraries which are "headers only" or "templates only". As an inspiration, please look at the distribution of SQlite or the Lemon Parser Generator; the author amalgamates the stuff into a single source file which is trivial to compile. Thank you.

    Read the article

  • HowTo parse numbers from string with BOOST methods?

    - by mosg
    Problem: Visual C++ 10 project (using MFC and Boost libraries). In one of my methods I'm reading simple test.txt file. Here is what inside of the file (std::string): 12 asdf789, 54,19 1000 nsfewer:22!13 Then I'm reading it and I have to convert all digits to int only with boost methods. For example, I have a list of different characters which I have to parse: ( ’ ' ) ( [ ], ( ), { }, ? ? ) ( : ) ( , ) ( ! ) ( . ) ( - ) ( ? ) ( ‘ ’, “ ”, « » ) ( ; ) ( / ) And after conversation I must have some kind of a massive of int's values, like this one: 12,789,54,19,1000,22,13 Maybe some one already did this job? PS. I'm new for boost. Thanks!

    Read the article

  • C++ Boost bind value type

    - by aaa
    hello. I look in documentation and source code but cannot figure out how to get return value type of boost bind functor. I am trying to accomplish following: 35 template<typename T,size_t N, class F> 36 boost::array<typename F::value_type, N> make_array(T (&input)[N], F unary) { 37 boost::array<typename F::value_type, N> array; 38 std::transform(input, input + N, array.begin(), unary); 39 return array; 40 } where F can be bind functor. the above does not work because functor does not have value_type. for that matter, is there standard interface for unary/binary functor as far as return value. Thanks

    Read the article

  • Problem with basic program using Boost Threads in c++

    - by Eternal Learner
    I have a simple program which creates and executes as thread using boost threads in c++. #include<boost/thread/thread.hpp> #include<iostream> void hello() { std::cout<<"Hello, i am a thread"<<std::endl; } int main() { boost::thread th1(&hello); th1.join(); } The compiler throws an error against the th1.join() line. It says " Multiple markers at this line - undefined reference to `boost::thread::join()' - undefined reference to `boost::thread::~thread()' "

    Read the article

  • thread destructors in C++0x vs boost

    - by Abruzzo Forte e Gentile
    Hi All These days I am reading the pdf Designing MT programs . It explains that the user MUST explicitly call detach() on an object of class std::thread in C++0x before that object gets out of scope. If you don't call it std::terminate() will be called and the application will die. I usually use boost::thread for threading in C++. Correct me if I am wrong but a boost::thread object detaches automatically when it get out of scope. Is seems to me that the boost approach follow a RAII principle and the std doesn't. Do you know if there is some particular reason for this? Kind Regards AFG

    Read the article

  • Linking error in OMNeT++ using Boost serialization library

    - by astriffe
    I'm very new to OMNeT++ and I'd like to use the serialization-library contained in the boost framework. However, when trying to use it, I get quite many errors such as: Description Resource Path Location Type undefined reference to `boost::archive::archive_exception::~archive_exception()' OmCCN line 36, external location: /home/alexander/UniBE/BT/simulator/boost-compiledLibs /include/boost/serialization/throw_exception.hpp C/C++ Problem . I guess the problem is that I didn't yet link the compiled library in OMNeT. I've had a look at the makefile but any changes there are worthless since it is generated automatically by makemake. Furthermore, trying to access the menu item 'makemake' in project properties OMNeT++ IDE throws an error (The currently displayed page contains invalid values). Can anyone give me a hint concerning what the error could cause or how to link the compiled library correctly? Any hints are very appreciated! cheers alex

    Read the article

  • Boost Shared Pointers and Memory Management

    - by Izza
    I began using boost rather recently and am impressed by the functionality and APIs provided. In using boost::shared_ptr, when I check the program with Valgrind, I found a considerable number of "Still reachable" memory leaks. As per the documentation of Valgrind, these are not a problem. However, since I used to use the standard C++ library only, I always made sure that any program written is completely free from memory leaks. My question is, are these memory leaks something to worry about? I tried using reset(), however it only decrements the reference count, doesn't deallocate memory. Can I safely ignore these, or any way to forcibly deallocate the memory allocated by boost::shared_ptr? Thank you.

    Read the article

  • C++ Boost bind value type {solved}

    - by aaa
    hello. I look in documentation and source code but cannot figure out how to get return value type of boost bind functor. I am trying to accomplish following: 35 template<typename T,size_t N, class F> 36 boost::array<typename F::value_type, N> make_array(T (&input)[N], F unary) { 37 boost::array<typename F::value_type, N> array; 38 std::transform(input, input + N, array.begin(), unary); 39 return array; 40 } where F can be bind functor. the above does not work because functor does not have value_type. for that matter, is there standard interface for unary/binary functor as far as return value. solution: it should be result_type. also equivalent defined are argument_type and first/second_argument_type for binary functions Thanks

    Read the article

  • handle null values for string when implementing IXmlSerializable interface

    - by user208081
    I have the following class that implements IXmlSerializable. When implementing WriteXml(), I need to handle the case where the string members of this class may be null values. What is the best way of handling this? Currently, I am using the default constructor in which all the string properties are initialized to empty string values. This way, when WriteXml() is called, the string will not be null. One other way I could do this is check using String.IsNullOrEmpty before writing each string in xml. Any suggestions on how I can improve this code? using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Xml.Serialization; using System.Globalization; namespace TCS.Common.InformationObjects { public sealed class FaxSender : IXmlSerializable { #region Public Constants private const string DEFAULT_CLASS_NAME = "FaxSender"; #endregion Public Constants #region Public Properties public string Name { get; set; } public string Organization { get; set; } public string PhoneNumber { get; set; } public string FaxNumber { get; set; } public string EmailAddress { get; set; } #endregion Public Properties #region Public Methods #region Constructors public FaxSender() { Name = String.Empty; Organization = String.Empty; PhoneNumber = String.Empty; FaxNumber = String.Empty; EmailAddress = String.Empty; } public FaxSender(string name, string organization, string phoneNumber, string faxNumber, string emailAddress) { Name = name; Organization = organization; PhoneNumber = phoneNumber; FaxNumber = faxNumber; EmailAddress = emailAddress; } #endregion Constructors #region IXmlSerializable Members public System.Xml.Schema.XmlSchema GetSchema() { throw new NotImplementedException(); } public void ReadXml(System.Xml.XmlReader reader) { throw new NotImplementedException(); } public void WriteXml(System.Xml.XmlWriter xmlWriter) { try { // <sender> xmlWriter.WriteStartElement("sender"); // Write the name of the sender as an element. xmlWriter.WriteElementString("name", this.Name.ToString(CultureInfo.CurrentCulture)); // Write the organization of the sender as an element. xmlWriter.WriteElementString("organization", this.Organization.ToString(CultureInfo.CurrentCulture)); // Write the phone number of the sender as an element. xmlWriter.WriteElementString("phone_number", this.PhoneNumber.ToString(CultureInfo.CurrentCulture)); // Write the fax number of the sender as an element. xmlWriter.WriteElementString("fax_number", this.FaxNumber.ToString(CultureInfo.CurrentCulture)); // Write the email address of the sender as an element. xmlWriter.WriteElementString("email_address", this.EmailAddress.ToString(CultureInfo.CurrentCulture)); // </sender> xmlWriter.WriteEndElement(); } catch { // Rethrow any exceptions. throw; } } #endregion IXmlSerializable Members #endregion Public Methods } }

    Read the article

  • Can I mix compile time string comparison with MPL templates?

    - by Negative Zero
    I got this compile time string comparison from another thread using constexpr and C++11 (http://stackoverflow.com/questions/5721813/compile-time-assert-for-string-equality). It works with constant strings like "OK" constexpr bool isequal(char const *one, char const *two) { return (*one && *two) ? (*one == *two && isequal(one + 1, two + 1)) : (!*one && !*two); } I am trying to use it in the following context: static_assert(isequal(boost::mpl::c_str<boost::mpl::string<'ak'>>::value, "ak"), "should not fail"); But it gives me an compilation error of static_assert expression is not an constant integral expression. Can I do this?

    Read the article

  • Determining Whether a String Is Contained Within a String Array (Case Insensitive)

    About once every couple of months I need to write a bit of code that does one thing if a particular string is found within an array of strings and something else if it is not ignoring differences in case. For whatever reason, I never seem to remember the code snippet to accomplish this, so after spending 10 minutes of research today I thought I'd write it down here in an effort to help commit it to memory or, at the very least, serve as a quick place to find the answer when the need arises again.So without further adieu, here it is:Visual Basic Version:If stringArrayName.Contains("valueToLookFor", StringComparer.OrdinalIgnoreCase) Then ... Else ... End IfC# Version:if (stringArrayName.Contains("valueToLookFor", StringComparer.OrdinalIgnoreCase)) ... else ...Without the StringComparer.OrdinalIgnoreCase the search will be case-sensitive. For more information on comparing strings, see: New Recommendations for Using Strings in Microsoft .NET 2.0.Happy Programming!Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

    Read the article

  • boost.serialization and lazy initialization

    - by niXman
    i need to serialize directory tree. i have no trouble with this type: std::map< std::string, // string(path name) std::vector<std::string> // string array(file names in the path) > tree; but for the serialization the directory tree with the content i need other type: std::map< std::string, // string(path name) std::vector< // files array std::pair< std::string, // file name std::vector< // array of file pieces std::pair< // <<<<<<<<<<<<<<<<<<<<<< for this i need lazy initialization std::string, // piece buf boost::uint32_t // crc32 summ on piece > > > > > tree; how can i serialize the object of type "std::pair" in the moment of its serialization?

    Read the article

< Previous Page | 13 14 15 16 17 18 19 20 21 22 23 24  | Next Page >