How to calculate expm of a matrix?

Hi all, I am trying to run the following but I got an erorr

Error in expm

if ~all(isfinite(A),'all')

How can I fix that error?

H=[ 0.650 0.202 0 0 0 0 0 0 0;0.202 0.650 -0.164 0.066 0 0 0 0 0;0 -0.168 0.779 0.165 0 0 0 0 0;0 0.066 0.165 0.648 -0.164 0.064 0 0 0;0 0 0 -0.164 0.776 0.164 0 0 0;0 0 0 0.064 0.164 0.649 0.168 0.051 0;0 0 0 0 0 0.168 0.547 0.168 0;0 0 0 0 0 0.051 0.168 0.650 -0.168;0 0 0 0 0 0 0 -0.168 0.547];
w=expm(H)

[John D'Errico]

I don't see any problem.

H=[ 0.650 0.202 0 0 0 0 0 0 0;0.202 0.650 -0.164 0.066 0 0 0 0 0;0 -0.168 0.779 0.165 0 0 0 0 0;0 0.066 0.165 0.648 -0.164 0.064 0 0 0;0 0 0 -0.164 0.776 0.164 0 0 0;0 0 0 0.064 0.164 0.649 0.168 0.051 0;0 0 0 0 0 0.168 0.547 0.168 0;0 0 0 0 0 0.051 0.168 0.650 -0.168;0 0 0 0 0 0 0 -0.168 0.547];
w=expm(H)
w =
       1.9549      0.39165    -0.032683     0.011087  -0.00063967   0.00021891   9.5344e-06   3.2559e-06  -1.0882e-07
      0.39165       1.9857     -0.32979      0.10175   -0.0092228    0.0030011   0.00017991   6.3289e-05  -2.6524e-06
    -0.033498      -0.3381       2.2357       0.3308    -0.027274    0.0089509   0.00051116   0.00017915  -7.3189e-06
     0.011043      0.10108      0.33106        1.972     -0.32879     0.097779    0.0087605    0.0032189  -0.00017481
  -0.00063785   -0.0091863    -0.027288     -0.32879        2.228      0.32891     0.026749    0.0097507  -0.00050801
   0.00021827    0.0029886     0.008956     0.097779      0.32891       1.9732      0.31834      0.12593    -0.009454
   9.5127e-06   0.00017938   0.00051137    0.0087605     0.026749      0.31834       1.7798      0.31831    -0.025872
   3.2487e-06   6.3108e-05   0.00017922    0.0032189    0.0097507      0.12593      0.31831       1.9715     -0.30885
  -1.0862e-07  -2.6465e-06  -7.3213e-06  -0.00017481  -0.00050801    -0.009454    -0.025872     -0.30885       1.7534

[Omar B.]

I got the following error

Error in expm 
if ~all(isfinite(A),'all')
 

[Steven Lord]

That doesn't look like the full error message. Can you post all the text displayed in red (and if there was any text displayed in orange, post that too) when you call expm?

[Omar B.]

I try to run it in the command window and just got the following

Attempt to execute SCRIPT all as a function:
/Users/jga/Documents/MATLAB/all.m

Error in expm (line 30)
if ~all(isfinite(A),'all')
 

[Omar B.]

[Walter Roberson]

Having that error message earlier would have helped a lot.

Answer 1

[Steven Lord]

You've written your own script all.m that's being called instead of the all function built into MATLAB. Rename or remove your file /Users/jga/Documents/MATLAB/all.m so MATLAB can call the built-in function.

[Omar B.]

Thank you so much.

[madhan ravi]

xD

Answer 2

[madhan ravi]

 clear expm

[Momo]

still not working.

[madhan ravi]

   which expm -all % try this in command window and paste your output
  /MATLAB/toolbox/matlab/matfun/expm.m
  /MATLAB/toolbox/symbolic/symbolic/@sym/expm.m  % sym method
  /MATLAB/toolbox/parallel/gpu/@gpuArray/expm.m  % gpuArray method

[madhan ravi]

By the way are you different person? Because the person has a different name. By the way show the full error message with how you’re calling it.

[Omar B.]

I could not access my account so my frind helped me. Sorry abou that.

 which expm -all % try this in command window and paste your output
  /MATLAB/toolbox/matlab/matfun/expm.m
  /MATLAB/toolbox/symbolic/symbolic/@sym/expm.m  % sym method
  /MATLAB/toolbox/parallel/gpu/@gpuArray/expm.m  % gpuArray method
/Applications/MATLAB_R2020a.app/toolbox/matlab/matfun/expm.m
/Applications/MATLAB_R2020a.app/toolbox/symbolic/symbolic/@sym/expm.m  % sym method
   /MATLAB/toolbox/matlab/matfun/expm.m
   ↑
Error: Invalid use of operator.
 

[Omar B.]

I posted the full error message I have gotten.

[Walter Roberson]

In MATLAB, when an error occurs, you are given an indication of which routine the error occurred in.

When the error occurs in a built-in function or a .p function or inside Simulink, then the error message just tells you which function the problem occurred in, and in that case always excludes the line of code that triggered the error.

When the error occurs in .m code, then (except for some cases involving caught errors that are re-thrown) the error always includes the line of code that the problem occurred on and includes an indication showing the line number in the code.

You show us a line of code that apparently triggered the error. In such a case, you would have been told the line number of the error. But you claim that you have shown us the entire error message.

Either you are mistaken about what you posting being the entire error message, or else your MATLAB is badly corrupted and needs to be reinstalled.

[Omar B.]

I understand, it was working before I update Matlab from 2017 to 2020. I do not know where is the problem.