Vector & ltfloat & gtx, y, z;

Vector & ltint & gt A, B, C, D;

f . open(" train _ data . txt ")；

Floating xx, yy, ZZ;

int aa，bb，cc，DD；

And (! f.eof())

{

f & gt& gtxx & gt& gtyy & gt& gtzz & gt& gtaa & gt& gtbb & gt& gtcc & gt& gtDD；

x . push _ back(xx)；

y . push _ back(YY)；

z . push _ back(ZZ)；

a . push _ back(aa)；

b . push _ back(bb)；

c . push _ back(cc)；

d . push _ back(DD)；

}

//x, y and z represent floating-point numbers, and a, b, c and d represent integer arrays.

The first three columns are imported into floating-point two-dimensional array A. What does this mean? 3->； 2?