Multiple values in the if-expression

My data-file is a (5x5) matrix. Each cell is a struct. In this struct there is 1 datafile (and other files like 'columnsheaders'). I have created a for-loop for 5 measurements en 5 subjects. So I tried to create an 'if-expression' to say that if specific values of that matrix are met, the program should break. But it gives the following error: "The expression to the left of the equals sign is not a valid target for an assignment."

if ((i_testen = 4) & (welke_pp = 1)) | ((i_testen = 4) & (welke_pp = 3)) | ((i_testen = 4) & (welke_pp) = 4) | ((i_testen) = 4 & (welke_pp = 5)) | (i_testen <= 4)
  break
RASI = data_sts(welke_pp,i_testen).VideoSignals(:, strcmp('RASI', data_sts(welke_pp,i_testen).VideoSignals_headers));
XY(2,1) = max(RASI)
XY(1,1) = 0;
Begin_Eind_sts.Begin(i_testen) = abs(XY(2,2));
Begin_Eind_sts.Eind(i_testen) = abs(XY(1,2));
close all
end

Answer 1

[Star Strider]

Your program is breaking on i_testen == 1 because at the end of the if statement conditions you have:

(i_testen <= 4)

that will cause the if condition to be true for i_testen == 1.

[Sam]

Oh yeah, I see it. I adjusted my code, but now there is another error...

if ((i_testen == 4) & (welke_pp == 1)) | ((i_testen == 4) & (welke_pp == 3)) | ((i_testen == 4) & (welke_pp == 4)) | ((i_testen) == 4 & (welke_pp == 5))
break
else
RASI = data_sts(welke_pp,i_testen).VideoSignals(:, strcmp('RASI', data_sts(welke_pp,i_testen).VideoSignals_headers)); %extract data
XY(2,1) = max(RASI) %get the maximum for RASI
XY(1,1) = 0; %set the minimum to zero
Begin_Eind_sts.Begin(i_testen) = abs(XY(2,2)); %store the data in a struct
Begin_Eind_sts.Eind(i_testen) = abs(XY(1,2));
close all %close all opened figures
end

The error is: "Index exceeds matrix dimensions.

Error in examen_matlabproberenpp1if (line 59) Begin_Eind_sts.Begin(i_testen) = abs(XY(2,2));".

[Star Strider]

What is in:

abs(XY(2,2))

and what are the dimension sizes of those contents?

[Sam]

Oh I see it. stupid mistake

[Star Strider]

Does your code work now?

[Sam]

Yes!

[Star Strider]

Great!

Answer 2

[Guillaume]

To compare values together use ==, the equality comparison operator, not = which is the assignment operator

[Guillaume]

Sam's comment copied here: I did what you said. But know I've got the problem that the program breaks when the values for i_testen = 1 and welke_pp = 1... It should not break when these variables have these values. The program should only break when the variables i_testen and welke_pp have the values I have specified behind the if-expression... Help?

if ... | ... | ... | ... | (i_testen <= 4)
  break
end

The last part of your if is OR i_testen <= 4 which is true for any value of welke_pp and any i_testen smaller than or equal to 4.

[Sam]

Oh yeah, I see it. I adjusted my code, but now there is another error...

if ((i_testen == 4) & (welke_pp == 1)) | ((i_testen == 4) & (welke_pp == 3)) | ((i_testen == 4) & (welke_pp == 4)) | ((i_testen) == 4 & (welke_pp == 5))
break
else
  RASI = data_sts(welke_pp,i_testen).VideoSignals(:, strcmp('RASI', data_sts(welke_pp,i_testen).VideoSignals_headers)); %extract data
XY(2,1) = max(RASI) %get the maximum for RASI
XY(1,1) = 0; %set the minimum to zero
Begin_Eind_sts.Begin(i_testen) = abs(XY(2,2)); %store the data in a struct
Begin_Eind_sts.Eind(i_testen) = abs(XY(1,2));
close all %close all opened figures
end

The error is: "Index exceeds matrix dimensions.

Error in examen_matlabproberenpp1if (line 59) Begin_Eind_sts.Begin(i_testen) = abs(XY(2,2));".

[Amir Semnani]

Thanks