Creating a vector using conditions and a cell.

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Julen Aramendi on 15 Jul 2021
Commented: Stephen23 on 16 Jul 2021
This is what I have in the workspace. I have 3 acceleration vectors (one column each): Ax (799x1 double), Ay(799x1 double) and Az(799x1 double). Also I have a cell called activities: activities (1x4 cell) with this code:
Activities={'Walking','Sitting','Standing','Laying'};
Walking=1;
Sitting=2;
Standing=3;
Laying=4;
What I want to do is to create another vector called "actid"(799x1 double) using this conditions:
if Ay>10
actid=1; %Walking
elseif Ay>5 & Ay<7.5
actid=2; %Sitting
elseif Ay<10 & Ay>9
actid=3; %Standing
elseif Ay<1 & Az>9
actid=4; %Laying
end
Running this code I can't get what I want.
I don't know if it is possible to do.
Thank you.
3 CommentsShow 1 older commentHide 1 older comment
Julen Aramendi on 16 Jul 2021
First of all, thanks for answering me.
Yeah, it is intentional. Yesterday I didn't explain very well what I want. What I want is that depending the values of the acceleration in X(Ax), Y(Ay) and Z(Az) axles, know if the person is walking, sitting, standing or laying. For that reason, in that case I don't need the acceleration in the axis X because with the other two acceleration axis (Y and Z) is enough.
I don't understand what you want to say with "operate on the entire vectors". Can you give me a simple example?
Thank you.
Stephen23 on 16 Jul 2021
"operate on the entire vectors". Can you give me a simple example?"
Simon Chan's answer is an example. Indexing would be another vectorized approach. See:
The difference is thinking in terms of matrices/arrays, not individual elements.

Simon Chan on 15 Jul 2021
Edited: Simon Chan on 15 Jul 2021
Try this:
Zeros in the matrix means all conditions are not meet
actid=(Ay>10) + (Ay>5 & Ay<7.5)*2 + (Ay<10 & Ay>9)*3 + (Ay<1 & Az>9)*4