Using operator keyword in equations invoving real numbers and complex numbers (errors I get)

[MBANS7A1]

Hello everyone, I got some code I wish to compute for some Mie data. However it has some errors relating to +,-,* and/ for complex numbers with int and doubles. I got code online for using operator with in a function with 2 parameters (for light scattering off skin molecules. But, the IDE (VS 2015) says operator only works with 1 parameter. When using both I cannot my equations invoving complex numbers. See below. There are some small errors I will mention too.

Functions of class VectorsMat1 (operator functions with 1 parameter):

complex<double> operator +(complex<double> res){
complex<double> result;

result.real() + real(res);
result.imag() + imag(res);
return result;
}

// addition of a real number a with a complex number B
complex<double> operator +(double a){
complex<double> B;
return a*U0 + B;
}


// addition of a complex number A with a real number b
complex<double> operator +(complex<double> A){
double b;
return A + b*U0;
}


// change sign of a complex number A
complex<double> operator -(complex<double> A){
return (-1.0*A);
}


// subtraction of a complex number B from a complex number A

complex<double> operator -(complex<double> A){
complex<double> B;
return A + (-B);
}


// subtraction of a complex number B from a real number a
complex<double> operator -(double a){
complex<double>B;
return a + (-B);
}


// subtraction of a real number b from a complex number A
complex<double> operator -(complex<double> A){
double b;
return A + (-b);
}


// multiplication of two complex numbers A and B
complex<double> operator *(complex<double> A){
complex<double>B;

real(A)*real(B) - imag(A)*imag(B);
real(A)*imag(B) + real(B)*imag(A);

return B;
}


// multiplication of a real with a complex number
complex<double> operator *(double a)
{
complex<double>B;

a*real(B);
a*imag(B);
return B;
}


// multiplication of a complex with a real number

complex<double> operator *(complex<double> A){
double b;
return b*A;
}


// division of a complex number A by a complex number B
complex<double> operator /(complex<double> A){
complex<double>B;
return 1 / pow(Cabs(B), 2)*A*compConj(B);
}


// division of a real number a by a complex number B
complex<double> operator /(int a){
complex<double>B;
return a*U0 / B;
}


// division of a complex number A by a real number b
complex<double> operator /(complex<double> A){
double b;
return 1 / b*A;
}

// division of a real number a by a complex number B
complex<double> operator /(int a){
complex<double>B;
return double(a)*U0 / B;
}

// division of a complex number A by a complex number B
complex<double> operator /(complex<double> A){
complex<double>B;
return 1 / pow(Cabs(B), 2)*A*compConj(B);
}
//division of a real number with a complex number
complex<double> operator *(double a){
complex<double>B;
a*real(B);
a*imag(B);
return B;
}

Now functions of VectorsMat2 (takes 2 parameters but IDE says operator function has too many parameters- got this from STOKES scattering of light from grains adapted to skin molecules)

struct complex
{

double re;
double im;
};

complex C(double a, double b){
complex res;

res.re = a;
res.im = b;
return res;
}





// addition of two complex number A and B
complex operator +(complex A, complex B) {

complex res;

res.re = A.re + B.re;
res.im = A.im + B.im;
return res;

}


// addition of a real number a with a complex number B
complex operator +(double a, complex B) {

return a*U0 + B;
}


// addition of a complex number A with a real number b
complex operator +(complex A, double b) {

return A + b*U0;

}


// change sign of a complex number A
complex operator -(complex A) {
return -1 * A;

}


// subtraction of a complex number B from a complex number A
complex operator -(complex A, complex B) {

return A + (-B);


}


// subtraction of a complex number B from a real number a
complex operator -(double a, complex B) {
return a + (-B);
}


// subtraction of a real number b from a complex number A
complex operator -(complex A, double b) {
return A + (-b);

}


// multiplication of two complex numbers A and B
complex operator *(complex A, complex B) {

complex res;

res.re = A.re*B.re - A.im*B.im;
res.im = A.re*B.im + B.re*A.im;
return res;

}

double CAbs(complex A) {
return sqrt((A*CConj(A)).re);

}

// multiplication of a real with a complex number
complex operator *(double a, complex B) {
complex res;

res.re = a*B.re;
res.im = a*B.im;
return res;

}


// multiplication of a complex with a real number
complex operator *(complex A, double b) {
return b*A;

}


// division of a complex number A by a complex number B
complex operator /(complex A, complex B) {
return 1 / pow(CAbs(B), 2)*A*CConj(B);

}


// division of a real number a by a complex number B
complex operator /(double a, complex B) {
return a*U0 / B;
}


// division of a complex number A by a real number b
complex operator /(complex A, double b) {
return 1 / b*A;
}


Errors in IDE log after building:

1st: CAbs function (VectorsMat2)->return sqrt((A*CConj(A)).re); (It's underlined at * and error says no operator "*" matches these operands, operand types are VectorsMat2::complex*VectorsMat2::complex

2nd: This is in a function called MieCalc with declaration
void MieCalc(double sizeParam, complex compRelRefrac, int NAng, complex S1[],
complex S2[], double& Qext, double& Qsca);

y = sizeParam * compRelRefrac; (double x complex number)
D[nmx - (n + 1)] = rn / y - 1 / (D[nmx - n] + rn / y); (this is in a for loop)
(At the division signs after rn (int) and before y-1 (with y-complex<double> type) it says no operator "/" matches the operands, operands are int/VectorsMat2::complex

I have the same kinds of error with
S2[j] = S2[j] + fn * (an*tau[j] + bn * Pi[j]); (this is in a for loop)
but just with it says no operator "*" matches the operands (with an being complex and tau an array storing doubles)

I need to help to sort these errors- which version of the operator functions are right (I tried with both VectorsMat1 and VectorsMat2 and they did not fix the errors). Hope this is not confusing.

[jonnin]

Can't you add a complex and a double together without a special function (etc)?? Most of these functions should not even need to exist. Complex<> type already supports all this stuff.

you can't multiply a complex and an array though. You can't multiply anything against an array! You need a loop or something to do that, or if tau is representing a complex in an array, you can promote it to a complex and then do it?

this is just a mess. Sorry, but it is.
I would rewrite it using complex and vectors. If you need your vectors to behave like mathmatical vectors, wrap them in a small class to give the math operator overloads. Then just write math statements, it should clean up nicely.

[MBANS7A1]

@jonnin tau is an array but it does not store complex numbers it stores double (like normal numbers-notice the tau[j]-j being the iteration). You said Complex<> already supports this-are you talking about the header:
include <complex> or something else. Sorry.. I will try to edit this an state it is in a loop.

[jonnin]

yes, <complex>.

I am saying that this
complex<double> result;
can do things like these:
// multiplication of a real with a complex number

without a hand-rolled function. Just do it.

result *= 3.14; //ok. Done.

Either you are showing the complex<> file (this is built into c++, no need to show it) or you have something someone hand-wrote to do the same thing (???) in which case its extra weird because its using <complex> ... ?