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matlabindexingaccelerometercat

Replacing Rows or Columns using Indexing (or efficient too solutions) instead of "Cat "

With Arduino, NeoGPS and an MPU6050 i log some data on a SD Card.

On Matlab i am trasforming the accelarations from MPU6050 from the byte values to m/s^2.

  1. The code loads the data on Matlab
  2. It extracts ax ay az
  3. Call a funcion that convert from byte to m/s^2
  4. It define the all the columns to be concatenated
  5. It concatenates the all the columns

I have a civil engineer back ground, so i am not very practical with coding.

I was wondering if exists a more efficient solution in particular using Indexing?

Here my dumb code 

%Open the file 
filename= uigetfile ('.csv');
fileID = fopen (filename);
logmpu6050 =csvread(filename);
fclose (fileID); 

%Converting acceleration from Byte to m/s^2
[ax,ay,az]=convms(logmpu6050);


%Replacing the old accelaration values with the new 
cat1=logmpu6050(:,1:8);
cat2=cat(2,ax,ay,az);
cat3=logmpu6050(:,13:15);
newlogmpu6050= cat(2,cat1,cat2,cat3);

Always thanks for your patience!

Solution

  • Because of the concatenation of ax, ay, az in the middle, it breaks the flow that you would use for indexing into logmpu6050 so you can't use indexing entirely to create the matrix.

    However if you want to do it in a single line, you could do something like: 

    newlogmpu6050 = [logmpu6050(:,1:8) ax ay az logmpu6050(:,13:15)];

    This still performs the desired concatenation, but you're not unnecessarily calling cat and to me this looks a lot neater.