How to concatenate two time arrays with the same time step?

Hi All

I have two time series both starting from 0 and show some duration,

t1 =[0,1,2,3,4]
t2= [0,1,2,3]

what I need to have is

Ttotal= [0,1,2,3,4,5,6,7,8]

this is what I did and is not working well :

Ttot= [];
resol=t1(2)-t1(1)
Ttot=[Ttot,t2+Ttot(end)+resol]

Answer 1

[James Tursa]

Ttotal = [t1,t1(end)+1+t2];

[farzad]

well, what if there are t1 to tn ?

then it should become

Ttotal = [Ttotal,Ttotal(end)+1+ti+1];

which is exactly what I wrote, but I tried it , it does not work and it gives me error :

Error: Dimensions of arrays being concatenated are not consistent.

[James Tursa]

You said you had two time series. Do you in fact have several time series? How are they stored ... I hope not in variables named as t1, t2, t3, ... tn. In which case your code gets very ugly very fast. Can you put them in cell arrays such as t{1}, t{2}, ... t{n}?

[farzad]

well, since I am reading each file in a loop, each time, I will read one of those time series ( one column is the time) and I have different arrays , with different lengths.

trying the above method, even did not work for two time series, the problem is not about how to index or call them , the problem is concatenating.

for the loop I do :

t is every time , the time signal I read from each file :

t=xlsread(timesignal.xlsx);
if i ==1:
    Ttot=t;
end
resol=t(2)-t(1);
if i>1
    Ttot= [Ttot,t+Ttot(end)+resol];
end

[James Tursa]

Why are you using resol? That was not in my answer. Using your code outline it would just be:

for i=1:whatever
    t=xlsread(timesignal.xlsx); % using appropriate file name nere
    if i ==1:
        Ttot=t;
    else
        Ttot= [Ttot,Ttot(end)+1+t];
    end
end

[farzad]

Of course you have used resol

In the above case, the resolution of time signal is 1 and you have summed

Ttot(end)+1+t

[farzad]

I actually tried it on command prompt and it works, I don't know why it's not working in my code

[James Tursa]

Maybe I misunderstood that they always started out at 0. If not, then maybe this is what you need

resol=Ttot(end)-t(1)+1;
Ttot=[Ttot,t+resol];

[farzad]

No they always start from zero. And in the above formula nothing is changed. You just moved Ttot

[farzad]

my code can only do the Ttot= t ; in the first loop but in the second loop it stops at second loop.

I checked the arrays dimensions in second loop :

if i>1
    Ttot= [Ttot,t+Ttot(end)+resol];
end

and they are, the right hand is the size of corresponding array and the left is just its name

size(Ttot) =    35     1
size(T(end) =     1     1
size(resol) =     1     1
size(t) =    20     1

[Walter Roberson]

t=xlsread(timesignal.xlsx);
if i ==1:
    Ttot=t.';
end
resol=t(2)-t(1);
if i>1
    Ttot= [Ttot,t.'+Ttot(end)+resol];
end

[farzad]

THANK YOU SO MUCH

[farzad]

dear Walter, shall you please check this question of mine ? it's not being viewed https://uk.mathworks.com/matlabcentral/answers/521105-how-do-i-draw-barh-using-both-axes-values