vertcat while filtering data

Hello all,

I am having difficulties getting to add to a matrix. I created an empty matrix named "bob". I have a 6 column matrix called "RPLIDARdata" that I want to pull the entire row out if a condition is met and put it in "bob". I want it to concatenate into the new matrix. "r" is the variable that I want to check and "i" is the iteration number in a for loop. The code I have tried goes as follows:

if r(i) > 1
  RPLIDAR(i,:) = bob(i,:);
end

(Yes, I know that my first code wouldn't have worked.) it throws this error

%Index exceeds matrix dimensions.

Error in fcmclusteringandoccupancymap (line 28)
       RPLIDAR(i,:) = bob(i,:);

I discovered vertcat so I entered this code in

vertcat(RPLIDARdata(i,:),bob)

I get this error

Error using vertcat
Dimensions of matrices being concatenated are not consistent.

Error in fcmclusteringandoccupancymap (line 28)
       vertcat(RPLIDARdata(i,:),bob);

Can anyone please help me with this? I would like for this to concatenate

[Jan]

[MOVED from section for answers] Caleb Lindhorst wrote:

I wanted the code to do this:

data = [0 2 3
        1 3 6
        2 8 5]
("r" values are in third column)
if r(i) > 3
  put it into a new matrix "bob"
bob  = [1 3 6
        2 8 5]

I eventually figured it out. The code I used goes like this

 if r(i) > 1
    bob = vertcat(bob,data(i,:))

It really helps filter my data and works great. "data" is the original data.

[Jan]

This looks like an iterative growing array. This is very inefficient. What is "i"? Did you read my answer? I still assume that this is easier - without a loop:

bob = data(r > 1, :)

[Caleb Lindhorst]

Sorry, Jan I didn't read it because I thought I got it figured out. I did but not as efficiently as what you have. Thank you for your help.

Answer 1

[Jan]

Do you mean:

bob = RPLIDAR(r > 1, :)

? If not, please post a small example of the inputs and the wanted output.