MATLAB: How to add time from 2 arrays

Question

Hi, I am a new user of Matlab. I have the following problem:

I have two columns like this way.

• a =102 sec
• a =135
• a =157
• b =189
• b =201
• a =222
• a =245
• b =290

Here the values are in seconds. I want to write a formula, which show the total duration of seconds of a and b.

For example: here total duration of a is = (157-102) + (245-222) = 78 seconds.

Please suggest me how to do it.

Thanks

Answer 1

C = {'a' 102
'a' 135
'a' 157
'b' 189
'b' 201
'a' 222
'a' 245
'b' 290}
cn = [C{:,2}]';
[~,~,c1] = unique(C(:,1));
t = [true;diff(c1)~=0];
s1 = accumarray(cumsum(t),cn,[],@(x)x(end)-x(1));
out = accumarray(c1(t),s1);