Problem with "if" command

I want to remane and reassigne some variable according 2 different cases

For example consider this script:

%In my script PBtime_b and PBtime_nb are obtained from other calculaion,
%(here i just assige a value) but im interested in a comparision between
%them in order to select other values

PBtime_b=5;
PBtime_nb=6;
Ab=5;
Cb=6;
Anb=7;
Cnb=8;

if PBtime_nb<=PBtime_b;
A=Ab
C=Cb
end

if PBtime_b>PBtime_nb;
A=Anb
C=Cnb
end
A

Unrecognized function or variable 'A'.

C
X=A+C

I would obtain A=Anb=5 and C=Cnb=6 but if i type A or C the script dosent recognize the variables

what i am doing wrong?

Answer 1

[Pooja Kumari]

Hi Pierto

It is my understanding that you are facing "Unrecognized function or variable 'A'." error. And you want to rename and reassign some variable according to two different cases.

Please follow below updated code for the same in which you want to assign A=Anb= 5 and C= Cnb=6 as follows:

%In my script PBtime_b and PBtime_nb are obtained from other calculaion,
%(here i just assige a value) but im interested in a comparision between
%them in order to select other values

PBtime_b=5;
PBtime_nb=6;
Ab=5;
Cb=6;
Anb=7;
Cnb=8;

%you want A = Anb = 5 and C = Cnb = 6
if PBtime_nb>=PBtime_b;
    A=Ab % Pbtime_nb = 6 > PBtime_b =5
    C=Cb % A = 5, C = 6;
end

if PBtime_b>PBtime_nb;
    Anb = A %Anb = 5
    Cnb = C %Cnb = 6
end
A
C
X=A+C

For more infomation on variable Pre-allocation you can refer to the below link :

https://in.mathworks.com/help/matlab/matlab_prog/preallocating-arrays.html

You can take help from workspace for checking correct variable assignment and you can refer to the link provided below:

https://in.mathworks.com/help/matlab/matlab_env/create-and-edit-variables.html#bvdmaif

Sincerely,

Pooja Kumari

Answer 2

[Torsten]

Should be

if PBtime_nb>PBtime_b

instead of

if PBtime_b>PBtime_nb;

[DGM]

Since the cases appear to be mutually exclusive and non-independent, I don't see why the structure shouldn't be reduced to if-else.

if PBtime_nb<=PBtime_b;
    A=Ab
    C=Cb
else
    A=Anb
    C=Cnb
end

[Torsten]

The OP's code with two separate if-statements is not wrong ...