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Sorting Date mm/dd/yyyy to yyyymmdd

asavage (28)
I am trying to read in some stock data from Yahoo and the date comes in this format mm/dd/yyyy. I want to sort the data and create a field that is yyyymmdd. If you look at my while statement, where I read in the file. I can't figure out how to change this so that it reads the date in without the "/" and changes the order of the input (so I can store the individual fields yyyy mm dd in the struct vector)

Thanks

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#include <iostream>
#include <string>
#include <fstream>
#include <vector>

using namespace std;
struct quote
{
	string date;
	double open;
	double high;
	double low;
	double close;
	double vol;
	double adjClose;
	
};

void printData(const vector<quote> q);
void highestPrice(const vector<quote> q);
void lowestPrice(const vector<quote> q);
void sortData(vector<quote> &q);
bool dateCompare(const quote &q1, const quote &q2)
{
	return q1.date < q2.date;	
}

int main(int argc, char *argv[])
{

	ifstream in(argv[1]);
	if(!in)
	{
		cout << "Unable to open "<< argv[1] << endl;	
	}
	else
		cout << "File opened " << endl;
	
	string str;	 // eat headers
	getline(in, str);
	cout << str << endl;	
	
	vector<quote> Quotes;
	quote entry; // temp
	int recCnt = 0;
	
	while (in >> entry.date >> entry.open >> entry.high 
		>> entry.low >> entry.close >> entry.vol 
		>> entry.adjClose)
	{
		Quotes.push_back(entry);	
		recCnt++;
				
	}
		
	in.close();
	
	printData(Quotes);
	cout << endl << "Summary Data " << endl;
	highestPrice(Quotes);
	lowestPrice(Quotes);
	
	
	cout << "The Number of Records Processed : " << recCnt << endl;	
	cout << "Sorted Data "<< endl;
	sortData(Quotes);
	printData(Quotes);
}

void printData(vector<quote> q)
{
	for(vector<quote>::const_iterator it = q.begin();
		it != q.end(); it++)
		{
			cout << it->date << " " << it->open << " " 
				<< it ->high << " " << it -> low << " "
				<< it-> close << " " << it-> vol << " "
				<< it-> adjClose << endl;	
		}

}

void highestPrice(vector<quote> q)

{
	vector<quote>::const_iterator it = q.begin();
	double highest = it->high;
	string highDate = it->date;
	for(vector<quote>:: const_iterator it = q.begin();
		it!= q.end(); it++)
		{
			if (it->high > highest)
			{
				highest = it->high;
				highDate = it->date;
			}
		}
	cout << "The highest price is " << highest << " and it occurred on "
		<< highDate << endl;
}

void lowestPrice(vector<quote> q)
{
	double lowest;
	string lowDate;
	vector<quote>::const_iterator it = q.begin();
	lowest = it->low;
	lowDate = it->date;
	
	for(it=q.begin(); it!= q.end(); it++)
	{
		if (it->low < lowest)
		{
			lowest = it->low;
			lowDate = it->date;	
		}	
	}
		
	cout << "The lowest price is " << lowest << " and it occurred on "
		<< lowDate << endl;
}

void sortData(vector<quote> &q)
{
	sort ( q.begin(), q.end(), dateCompare);	
	
}
helios (17574)
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//s ~ "MM/DD/YYYY"
s=s.substr(6,4)+s.substr(0,2)+s.substr(3,2);
//s ~ "YYYYMMDD"
asavage (28)
This works for all instances when the month field is 2 digits long. But for months 1-9 it doesn't work.

How can I tell if there are 2 numbers in the month field or one?
JLBorges (13770)
Parsing it using a std::istringstream is simple.
(though it is not the most efficient way of doing this)

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#include <string>
#include <sstream>
#include <iomanip>

std::string to_yyyymmdd( const std::string& mdyy )
{
    std::istringstream stm(mdyy) ;
    int month, day, year ;
    char sep1, sep2 ;
    if( ( stm >> month >> sep1 >> day >> sep2 >> year ) && (sep1=='/') && (sep2=='/')
        && stm.eof() && (year>0) && (month>0) && (month<13) && (day>0) && (day<32) )
    {
        if( year < 1000 ) year += 2000 ;
        std::ostringstream ostm ;
        auto width = std::setw(2) ;
        auto fill = std::setfill('0') ;
        ostm << year << width << fill << month  << width << fill << day ;
        return ostm.str() ;
    }
    else { /* format error */ return "invalid date: " + mdyy ; }
}
Last edited on
helios (17574)
To avoid confusion in the future, MM in a format string is typically understood as meaning "the month padded with zeroes to two digits". Likewise for DD and YYYY.
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