### Cannot subtract values from elements of a vector

Hello,

I would like to perform an operation with vectors, but I lost my way. Help would be appreciated.

The operation is, vv = v -(alpha +1)*i; where v and vv are vectors. I need to subtract (alpha +1 ) * i from each element of the vector v, and define those subtracted elements inside my vector vv.

 ``1234567891011121314151617181920212223242526272829303132333435`` `````` int main () { const int N = 16 * 2; double eta = 0.25; const double alpha = 1.2; //these are constants i use. complex w(0.0, 1.0); //Defining a complex number here. double z = w.im(); //using its imaginary part. const double MAX_ELEMS = N * eta; const double MAXIM_ELEMS = N; vector vv; vector v; for (double i = 0; v.size() < MAX_ELEMS; i += eta) { v.push_back(i); for (double j = v.at(1) - (alpha + 1)*z ; vv.size() < MAXIM_ELEMS; j = v.at(i++)) { vv.push_back(j); } } // Want to print my vv vector, at the end of this calculation. cout << "my vv vector contains:"; for (unsigned i = 0; i < vv.size(); i++) cout << ' ' << vv.at(i); cout << '\n'; return 0; }``````
You are saying one thing but in the code you are doing another thing. You should decide at first what you are going to do.
I am pretty new to programming, so my code should be wrong. Indeed what I want to do is to get

vv = v - (alpha + 1) * i,

where v is a vector 0 ---> (N-1) * eta, with eta increments. Could you maybe point out to my mistakes ?

I will need to use these two vectors later on for other calculations as well.
Last edited on
I still need help with this, anyone?
 ``12345678910`` ``````vector vv; vv.reserve( N ); vector v; v.reserve( N ); for ( int i = 0; i < N; i++ ) { v.push_back( i * eta ); vv.push_back( v.back() - ( alpha + 1 ) * i ); }``````
Indeed it works, thank you very much!

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