Using Poco-1.12.4-release and g++ (Ubuntu 9.4.0-1ubuntu1~20.04.1) 9.4.0, The recommended example code for DatagramSocket Receive in this doc:
https://pocoproject.org/slides/200-Network.pdf
compiles with this error:
dgs.cpp: In function ‘int main(int, char**)’:
dgs.cpp:34:33: error: no matching function for call to ‘Poco::Net::DatagramSocket::DatagramSocket(Poco::Net::SocketAddress&)’
34 | Poco::Net::DatagramSocket dgs(sa);
What happened? Is there a fix for this example?
Thanks
The code is:
// DatagramSocket receive example
#include "Poco/Net/DatagramSocket.h"
#include "Poco/Net/SocketAddress.h"
#include <iostream>
int main(int argc, char** argv)
{
Poco::Net::SocketAddress sa(Poco::Net::IPAddress(), 514);
Poco::Net::DatagramSocket dgs(sa);
char buffer[1024];
for (;;)
{
Poco::Net::SocketAddress sender;
int n = dgs.receiveFrom(buffer, sizeof(buffer)-1, sender);
buffer[n] = '\0';
std::cout << sender.toString() << ": " << buffer << std::endl;
}
return 0;
}
I tried this:
Poco::Net::SocketAddress sa(Poco::Net::IPAddress(), 514);
Poco::Net::DatagramSocket dgs(Poco::Net::SocketAddress::IPv4);
dgs.connect(sa);
It compiles, but is it correct?
Code:
using ColumnIndexVector = std::vector<int>;
using ByteVector = std::vector<BYTE>;
void CCreateReportDlg::GetColumnIndexesToExclude()
{
const CString strSection = theApp.GetActiveScheduleSection(_T("Options"));
ByteVector vData = theApp.GetProfileVector(strSection, _T("AssignStatesEx"));
ColumnIndexVector vTemp(vData.begin(), vData.end()); // This converts BYTE to int
m_vColumnIndexesToExclude = vTemp;
}
Is there any way to avoid the requirement for vTemp without manually iterating vData and casting from BYTE to int?
Yes, just use assign(). IDK if you need to use clear() as well, but probably not. Just step through the runtime code the first time to know.
m_vColumnIndexesToExclude.assign(vData.begin(), vData.end());
Here's a test program:
#include <windows.h>
#include <iostream>
#include <vector>
using namespace std;
using ColumnIndexVector = std::vector<int>;
using ByteVector = std::vector<BYTE>;
int main(int argc, char* argv[])
{
cout << "Test" << endl;
ByteVector bytes = {'A', 'B', 'C', 'D'};
ColumnIndexVector colVector;
for ( auto _val: bytes)
{
cout << _val << endl;
}
colVector.assign(bytes.begin(), bytes.end());
for ( auto _val : colVector)
{
cout << _val << endl;
}
return 0;
}
wanting to ask how to change this pass by reference into pass by pointer, cause some of my school works need pass by pointer and i doesn't really understand how to modified this code using pass by pointer
void convert(string &s){
for (int i =0; i<s.length(); i++){
s[i] = toupper(s[i]);
}
}
int main(){
string name;
cout<<"Enter your name"<<endl;
getline(cin,name);
convert(name);
cout<<name<<endl;
return 0;
}
First of all, there are some minor errors in the code.
Inlcude necessary headers.
Use std:: namespace prefix.
#include <iostream>
#include <string>
#include <cctype>
void convert(std::string &s){
for (int i =0; i < s.length(); i++){
s[i] = std::toupper(s[i]);
}
}
int main(){
std::string name;
std::cout << "Enter your name: ";
std::getline(std::cin, name);
convert(name);
std::cout << name << std::endl;
return 0;
}
Using pointer version?
#include <iostream>
#include <cstdio>
#include <cstring>
#include <cctype>
#define SIZE 100
void convert(char *s, size_t size){
for (int i =0; i < size; i++){
s[i] = std::toupper(s[i]);
}
}
int main(){
char name[SIZE];
std::cout << "Enter your name: ";
std::fgets(name, SIZE, stdin);
convert(name, strlen(name));
std::cout << name << std::endl;
return 0;
}
Another version using pointers
#include <iostream>
#include <string>
#include <cctype>
void convert(std::string *s){
for (int i =0; i < s -> length(); i++){
(*s)[i] = std::toupper((*s)[i]);
}
}
int main(){
std::string *name = new std::string();
std::cout << "Enter your name: ";
std::getline(std::cin, *name);
convert(name);
std::cout << *name << std::endl;
delete name;
return 0;
}
http://creativemachines.cornell.edu/eureqa/
http://code.google.com/p/eureqa-api/
Is there a way of interfacing Eureqa with R?
(windows os)
Perhaps:
Rcpp package and:
The simplest possible complete C++ program using the Eureqa API:
#include eureqa/eureqa.h
#include iostream
int main(int argc, char *argv[])
{
// initialize data set and options
eureqa::data_set data("my_data.txt");
eureqa::search_options options("y = f(x)");
// connect to a eureqa server
eureqa::connection conn("127.0.0.1");
conn.send_data_set(data);
conn.send_options(options);
conn.start_search();
// display results
eureqa::search_progress progress;
eureqa::solution_frontier solutions;
while (conn.query_progress(progress))
{
solutions.add(progress.solution_);
std::cout << progress.summary() << std::endl;
std::cout << solutions.to_string() << std::endl;
}
return 0;
}
I want to save a QList<int> to my QSettings without looping through it.
I know that I could use writeArray() and a loop to save all items or to write the QList to a QByteArray and save this but then it is not human readable in my INI file..
Currently I am using the following to transform my QList<int> to QList<QVariant>:
QList<QVariant> variantList;
//Temp is the QList<int>
for (int i = 0; i < temp.size(); i++)
variantList.append(temp.at(i));
And to save this QList<Variant> to my Settings I use the following code:
QVariant list;
list.setValue(variantList);
//saveSession is my QSettings object
saveSession.setValue("MyList", list);
The QList is correctly saved to my INI file as I can see (comma seperated list of my ints)
But the function crashes on exit.
I already tried to use a pointer to my QSettings object instead but then it crashes on deleting the pointer ..
QSettings::setValue() needs QVariant as a second parameter. To pass QList as QVariant, you have to declare it as a Qt meta type. Here's the code snippet that demonstrates how to register a type as meta type:
#include <QCoreApplication>
#include <QDebug>
#include <QMetaType>
#include <QSettings>
#include <QVariant>
Q_DECLARE_METATYPE(QList<int>)
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
qRegisterMetaTypeStreamOperators<QList<int> >("QList<int>");
QList<int> myList;
myList.append(1);
myList.append(2);
myList.append(3);
QSettings settings("Moose Soft", "Facturo-Pro");
settings.setValue("foo", QVariant::fromValue(myList));
QList<int> myList2 = settings.value("foo").value<QList<int> >();
qDebug() << myList2;
return 0;
}
You might have to register QList as a meta-type of its own for it to work. This is a good starting point to read up on meta-types in Qt: http://qt.nokia.com/doc/4.6/qmetatype.html#details .
I was also struggling with this ... and I believe I now have a decent solution.
I hope this saves someone the trouble, it caused me.
#include <QCoreApplication>
#include <QSettings>
#include <QList>
#include <QDataStream>
#include <QVariant>
#include <QVariantList>
#include <QDebug>
#include <deque>
template <class T> static QVariant toVariant(const QList<T> &list)
{
QVariantList variantList;
variantList.reserve(list.size());
for (const auto& v : list)
{
variantList.append(v);
}
return variantList;
}
template <class T> static QList<T> toList(const QVariant &qv)
{
QList <T> dataList;
foreach(QVariant v, qv.value<QVariantList>()) {
dataList << v.value<T>();
}
return dataList;
}
void Gen()
{
QList<QString> data {"hello", "world","how", "are", "you"};
QList<int> ages {10,20,30,40};
QSettings setup("stuff.ini", QSettings::IniFormat);
setup.beginWriteArray("rules");
for (int groups=0;groups<3;groups++)
{
setup.setArrayIndex(groups);
setup.setValue("rule",QString("Rule-%1").arg(groups));
setup.setValue("data", toVariant (data));
setup.setValue("ages", toVariant (ages));
}
setup.endArray();
setup.sync();
}
void Read()
{
QSettings setupR("stuff.ini", QSettings::IniFormat);
int rule_count = setupR.beginReadArray("rules");
for (int groups=0;groups<rule_count;groups++)
{
setupR.setArrayIndex(groups);
QString nameRead = setupR.value("rule").toString();
QList<QString> dataRead = toList<QString>(setupR.value("data"));
qDebug() << "Rule " << groups;
qDebug() << "Rule Read" << nameRead;
qDebug() << "Data Read2" << dataRead;
}
}
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
// Write
Gen();
// Read
Read();
exit(0);
//return a.exec();
}
You should end up with an INI file which looks like this ...
[rules]
1\ages=10, 20, 30, 40
1\data=hello, world, how, are, you
1\rule=Rule-0
2\ages=10, 20, 30, 40
2\data=hello, world, how, are, you
2\rule=Rule-1
3\ages=10, 20, 30, 40
3\data=hello, world, how, are, you
3\rule=Rule-2
size=3
The nice thing here is you can edit this outside of QT (Just be careful) ...