How to properly access values in an array, within a cell array, within a struct?

I have a struct called myStruct with 2 fields:

Field Value

light 4x2 cell

dark 4x2 cell

If I click on myStruct.light, I see the following arrays listed

2178x3860 double 2178x3860 double

2178x3860 double 2178x3860 double

2178x3860 double 2178x3860 double

2178x3860 double 2178x3860 double

and if I click on one of these cells, say myStruct.light{3,2}, I can then see the data in that cell's 2178x3860 array.

I would like to write a line in the Command Window that enables me to extract a range of values in myStruct.light{3,2}. Let's suppose that I want to calculate the mean of all values in a 2x4 array from the top left corner of myStruct.light{3,2}

If I enter

topleft=amberLED.light{3,2}(1:2,1:4)

in the command window, it seems to work ok. A 2x4 matrix called topleft is output:

topleft =

2356 2284 2347 2350

2273 2403 2288 2342

But when I then type:

mean = mean(topleft, 'all')

I get the following error message returned:

Index in position 1 exceeds array bounds (must not exceed 1).

Please can you advise me where I'm going wrong?

Answer 1

[Walter Roberson]

mean = mean(topleft, 'all')

You got the error the second time you tried to use the function mean(). After the first time you called mean(), you have replaced the function mean() with the array mean .

Avoid using variable names that are the same as the names of important functions.

[Steve Francis]

Thank you. It works when I change the variable name.

mean1 = mean(topleft, 'all')