MATLAB: On multiple logical test failing in if statement

if statementMATLABmultiple logical conditions

Hello, I am trying to run an if statement with multiple conditions as below,
 if abs(a-a_t)>0.0001 && abs(b-b_t)>0.00001 && abs(c-c_t)>0.0001 && abs(d-d_t)>0.00001
 x=0;
 y=0;
 end
Even when all the conditions are satisfied, the values of x and y are not updated. But, it works if we have just two conditions (I've tried different combinations of two variable values which work, but using all conditions in separate brackets doesn't work). MATLAB documentation says that multiple logical operators could be used, but it doesn't seem to be working in my case. Is there a limit to the number of logical operators that could be combined? Or, am I missing something?
Thanks for your advice.

Best Answer

Apparently the issue was likely one of the cases wasn't actually T or some similar misstep, but illustrates the difficulties inherent in writing code with sequentially-named variables. Use arrays instead.
If had defined a variable data and commensurate test value, then the following could be written much more succinctly and much easier to both code and debug--
data=[a b c ...];                        % the data array (*)
test=[a_t b_t c_t ...];                  % associated test values
lims=[0.0001 0.00001, 0.0001, ...];      % and criteria
if all(abs(data-test))<lims              % see if all ok
  ....
(*) And, of course, this is not intended to suggest one should write the specific line concatenating all these variables to create the one; instead use the vector features of Matlab when creating the variables initially, either by reading one or more files or the result of other calculations, whatever.
Don't create the problem in the beginning to have to try to fix later...
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