Re: [ublas] file io/ ublas vector members

From: Michael Stevens (mail_at_[hidden])
Date: 2005-03-29 06:14:22

Will,

> 2)I am having problems with ublas vectors.  I can't seem to load ublas
> vectors with data from a file.  This is the method I use with std vectors:
>
> vector<float> v;
> ifstream infile("/home/will/roughwork/numbers.dat");
> istream_iterator<float> fin(infile),end;
> v.assign(fin,end);

> What is the best way load file data into a ublas vector?
I would use
        infile >> v;
This works fine for data stored as text using 'infile << v'.
'operator >> '  does all the hard work of formating and making sure the number 
of elements are correct.

Is there a reason for not using 'operator >>'  or are you trying to do some 
sophisticated serilaisation of uBLAS containers?

Incidentally I am not sure where the syntax 
        v.assign(fin,end);
comes from. It not part of uBLAS!

> I can not get this to work with a ublas vector.  Nor can I use copy, or
> assign from a std vector into a ublas vector.

Without detailed testing the following compiles fine with Boost_1_32_0
        std::vector<float> sv;
        ublas::vector<float> uv;
        std::copy (sv.begin (), sv.end (), uv.begin ());
        std::copy (uv.begin (), uv.end (), sv.begin ());

Michael