numeric下的牛逼，可以炒股了。

不用担心，你没有上当，数据计算，分析一系列的变化非常有用，例如分析股票值的变化，所涉及的就是numeric的计算，请看，相信你不再害怕查文档，不再害怕函数原型

分别解说:

下面是函数原型，不要被函数原型吓到了，下面有具体的代码。

1

template<class InIt, class T>
T accumulate(InIt first, InIt last, T val);
template<class InIt, class T, class Pred>
T accumulate(InIt first, InIt last, T val, Pred pr);

2

template<class InIt1, class InIt2, class T>
T product(InIt1 first1, InIt1 last1,
Init2 first2, T val);
template<class InIt1, class InIt2, class T,
class Pred1, class Pred2>
T product(InIt1 first1, InIt1 last1,
Init2 first2, T val, Pred1 pr1, Pred2 pr2);
3
template<class InIt, class OutIt>
OutIt adjacent_difference(InIt first, InIt last,
OutIt result);
template<class InIt, class OutIt, class Pred>
OutIt adjacent_difference(InIt first, InIt last,
OutIt result, Pred pr);
4

template<class InIt, class OutIt>
OutIt partial_sum(InIt first, InIt last,
OutIt result);
template<class InIt, class OutIt, class Pred>
OutIt partial_sum(InIt first, InIt last,
OutIt result, Pred pr);

一：accumulate

#include<iostream>
#include<string>
#include<numeric>
#include<vector>
#include<functional>
using namespace std;
int jiayibai(int a,int b){
return a+b*2;
}
int main(){
int a[]={1,2,3,4,5,6,7,8,9,10};
vector<int>v(a,a+10);
int sum=accumulate(v.begin(),v.end(),0);
cout<<sum<<endl;
int sum1=accumulate(v.begin(),v.end(),0,jiayibai);
cout<<sum1<<endl;
int sum2=accumulate(v.begin(),v.end(),0,minus<int>());
cout<<sum2<<endl;
system("pause");
return 0;
}

二：inner_product

#include<iostream>
#include<string>
#include<vector>
#include<functional>
#include<numeric>
using namespace std;
int xiangjian (int x, int y) {return x-y;}
int xiangjia (int x, int y) {return x+y;}

int main(){
int a[]={1,2,3,4,5};
int b[]={5,4,3,2,1};
vector<int>v(a,a+5);
vector<int>vv(b,b+5);
int ji1=inner_product(v.begin(),v.end(),vv.begin(),0);
cout<<ji1<<endl;
int ji2=inner_product(v.begin(),v.end(),vv.begin(),0,xiangjian,xiangjia);
cout<<ji2<<endl;
int ji3=inner_product(v.begin(),v.end(),vv.begin(),0,minus<int>(),divides<int>());
cout<<ji3<<endl;
system("pause");
return 0;
}

三：adjacent_difference

#include<iostream>
#include<string>
#include<vector>
#include<numeric>
using namespace std;
int xiangjia(int a,int b){
return a+b;
}
int main(){
int a[]={1,3,5,7,10};
vector<int>v(a,a+5);
vector<int>vv(5);
adjacent_difference(v.begin(),v.end(),vv.begin());
for(vector<int>::iterator itera=vv.begin();itera!=vv.end();++itera){
cout<<*itera<<" ";
}
cout<<endl;
adjacent_difference(v.begin(),v.end(),vv.begin(),xiangjia);
for(vector<int>::iterator iterb=vv.begin();iterb!=vv.end();++iterb){
cout<<*iterb<<" ";
}
cout<<endl;
adjacent_difference(v.begin(),v.end(),vv.begin(),minus<int>());
for(vector<int>::iterator iterc=vv.begin();iterc!=vv.end();++iterc){
cout<<*iterc<<" ";
}
cout<<endl;
system("pause");
return 0;
}

四：partial_sum

#include<iostream>
#include<string>
#include<vector>
#include<numeric>
#include<functional>
using namespace std;
int xiangjia(int a,int b){
return a+b;
}
int main(){
int a[]={4,5,7,3,6};
vector<int>v(a,a+5);
vector<int>vv(5);
partial_sum(v.begin(),v.end(),vv.begin(),xiangjia);
for(vector<int>::iterator itera=vv.begin();itera!=vv.end();++itera){
cout<<*itera<<" ";
}
cout<<endl;
partial_sum(v.begin(),v.end(),vv.begin());
for(vector<int>::iterator iterb=vv.begin();iterb!=vv.end();++iterb){
cout<<*iterb<<" ";
}
cout<<endl;
partial_sum(v.begin(),v.end(),vv.begin(),multiplies<int>());
for(vector<int>::iterator iterc=vv.begin();iterc!=vv.end();++iterc){
cout<<*iterc<<" ";
}
cout<<endl;
system("pause");
return 0;
}