Sum and Average of column in Matrix

I have a 27 x 34 table, which has different column headings such as 'start freq, end freq, and Duration90s'.

I'm wanting to calculate the sum and then the average of only one column. That being 'Duration90s'

I've tried: sum('Duration90s')

meandur = sum('Duration90s)/27

*27 indicates the number of entries

I have changed the code a few times but I keep receiving the sum = 1058

and the mean dur = 39.1852

However the correct answer should be sum = 14

and the mean dur = 0.518519

Answer 1

[madhan ravi]

Wanted=T(:,'Duration90s');% here T is your table
% Google how to access data from table 
sum(Wanted)
mean(Wanted)

[Rachael Courts]

Hi Madhan,

Thank you for your quick response. I used the code you suggested (after definng T as my table). However, I keep receiving an Error using sum

Invalid data type. First argument must be numeric or logical.

[madhan ravi]

Upload your table as .mat file.

[Rachael Courts]

Attempted: Not a binary

MAT-file. Try load -ASCII to read as text.

[madhan ravi]

Attach your file here by clicking the paper clip button.

[Rachael Courts]

Thank-you

[Rachael Courts]

I actually got it to work by:

sum(Wanted.Duration90s)

mean(Wanted.Duration90s)

[madhan ravi]

Ah, yes also:

Wanted=T{:,'Duration90s'}; % {} was missing