Complex Numbers problem

I am having problems getting this Complex Numbers program to work correctly. i want to display using format a+bi the addition, subtraction and multiplication of 2 complex numbers.Can anyone reply today?
class Complex
     private double realPart, imaginaryPart;
     public Complex()
          realPart = 0.0;
          imaginaryPart = 0.0;
     public static void main(String [] args)
          Complex c;
          double res;
          c = new Complex();
          Screen.message("-------------------MENU----------------------------");
          Screen.newline(2);
          Screen.message("Please enter a number: ");
          Keyboard.readDouble();
          res = c.get_realPart();
          Screen.newline();
          Screen.message("Please enter a second number: ");
          Keyboard.readDouble();
          res = c.get_imaginaryPart();
          Screen.newline(2);
          Screen.message("--------------------------------------------------");
          Screen.newline();
          Screen.message("     Designed by Niall Magner               ");
          Screen.newline();
          Screen.message("--------------------------------------------------");
          Screen.newline(2);
          Screen.writedouble(res);
          Screen.newline();
          Screen.writedouble(res);
          Screen.newline();
          Screen.writedouble(res);
          Screen.newline(2);
     public double get_realPart()
          return realPart;
     public double get_imaginaryPart()
          return imaginaryPart;
     public void addComplexNum(Complex n1, Complex n2)
          realPart = n1.get_realPart() + n2.get_realPart();
          imaginaryPart = n1.get_imaginaryPart() + n2.get_imaginaryPart();
          Screen.message("-----------------------------------------------");
          Screen.newline(2);
          Screen.message("Number 1 is: " + realPart);
          Screen.message(" + " + imaginaryPart + "i");
          Screen.newline();
          Screen.message("Number 2 is: " + realPart);
          Screen.message(" + " + imaginaryPart + "i");
          Screen.newline();
          Screen.message("-----------------------------------------------");
          Screen.newline(2);
     public void subtractComplexNum(Complex n1, Complex n2)
          realPart = n1.get_realPart() - n2.get_realPart();
          imaginaryPart = n1.get_imaginaryPart() - n2.get_imaginaryPart();
          Screen.message("-----------------------------------------------");
          Screen.newline(2);
          Screen.message("Number 1 is: " + realPart);
          Screen.message(" - " + imaginaryPart + "i");
          Screen.newline();
          Screen.message("Number 2 is: " + realPart);
          Screen.message(" - " + imaginaryPart + "i");
          Screen.newline();
          Screen.message("-----------------------------------------------");
          Screen.newline(2);
     public void multiplyComplexNum(Complex n1, Complex n2)
          realPart = n1.get_realPart() * n2.get_realPart();
          imaginaryPart = n1.get_imaginaryPart() * n2.get_imaginaryPart();
          Screen.message("-----------------------------------------------");
          Screen.newline(2);
          Screen.message("Number 1 is: " + realPart);
          Screen.message(" * " + imaginaryPart + "i");
          Screen.newline();
          Screen.message("Number 2 is: " + realPart);
          Screen.message(" * " + imaginaryPart + "i");
          Screen.newline();
          Screen.message("-----------------------------------------------");
          Screen.newline(2);
Any help greatly appreciated.
Niall Magner

There are several problems with this code. You never call the add method, so the numbers are never going to be added. You never load up a complex number to add either.
Try doing something a bit more like this:
read a float from the keyboard
read another float from the keyboard
Create a complex number from this float
Complex complex1 = new Complex();
complex1.realPart = first number from above;
complex1.imaginaryPart = second number from above;
do this again to get the second complex number
then add the numbers together
Complex complexSum = new Complex
complexSum.addComplexNum(complex1, complex2)
print complexSum.realPart + "+i" + complexSum.imaginaryPart;
then do the other operations you wantI would also advise that you take a course in Java Programming, cos the code you have posted is truely awful.

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Hi Biz
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string, so when you convert the array to a spreadsheet string, the
numbers would be converted to real data.
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the above-mentioned "Numeric: Re/Im to Complex" function. It worked for
me, so if you can't follow what I am describing, send me an email and I
can email you what I did (LV 5.1.1).
Paul
Biz wrote:
> Having trouble converting array to spreadsheet string, storing the
> file and coverting back to array with complex numbers
>
> I am working with a network analyzer. I have arrays made of 5 columns
> the first consisting of an integer and the next four consisting of
> complex numbers. I am converting the array into a spreadsheet string
> and then saving the file using the write characters to a file VI. That
> seems to work well as when I open the file in Excel all the data is
> there. However when I try to reverse the process, open file and
> convert back to array, I loose some of the data. Specifically the
> imaginary parts of my complex numbers are all going to zero. I have
> narrowed down the problem to be in the conversion from spreadsheet
> string to array and vice versa. I think the problem may be with the
> 'format' input to the VI. I do not have an adequate resource for this
> so I am not sure what to put in to accomplish my task. Any takers?
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email: [email protected]
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Hi Chaks,
try this:
(Get Waveform components, convert to complex DBL)
Message Edited by GerdW on 01-28-2008 09:23 AM
Best regards,
GerdW
CLAD, using 2009SP1 + LV2011SP1 + LV2014SP1 on WinXP+Win7+cRIO
Kudos are welcome
Attachments:
ToCDB.png ‏1 KB

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Fedor wrote:
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