how to return for loop tables to a table

Hi All

I want to return two tables inside a for loop to the main table outside.

mat_bac is the main table outside the for loop.

Data_1 for i and data_2 for i+1 are the tables I need to return to mat_bac. So that at the end it's not overwritten.

Thank you.

I have a main table outside the for loop

frame    par1         par2        par3    
_____    ________    ________    ______   

1           268.13      143.89       25.376    
1           85.818      84.414       27.488    
1           173.56      165.74       28.634    
1            651.7      471.31       23.389    
1           678.37      317.05       32.631    
1           611.04      94.878       21.631    
1           451.42      353.31       26.549    
1           177.49      515.96       26.596    
1           287.63      367.65       29.248    
1            492.5      62.251       46.735    
2           265.99      141.51       25.046    
2            88.22      80.331       28.023    
2           174.12      168.28       28.08     
2           286.95      371.45       29.611    
2           681.29      322.52       33.3     
2           486.08      63.945       50.203    
2           614.1       96.111       21.493    
2           181.45      512.15       26.459    
2           648.41       474.4       25.315    
2           267.26       495.39      25.222    
2          393.29        249.04      29.059    
3	    64.80742	146.0646	27.3122
3	    290.8602	167.7889	35.7585
3	  477.655	 89.51805	21.64952
3	344.113	        44.36785	44.03939
3	621.3208	 408.272	24.24406
3	310.5134	329.8202	21.51631
3	72.62675	113.7154	23.65932
3	520.6362	404.6039	22.32997
4	289.5507	168.0988	35.5876
4	476.9346	91.47729	20.63287
4	656.3892	334.381	        27.20086
4	65.7696         141.7556	27.21767
4	294.9997	330.3788	37.8143
4	549.6827	59.24164	22.09339
4	327.6798	52.62152	24.81
4	225.9563	516.5291	26.54855
4	264.0543	284.7716	36.37305
4	133.1544	124.9854	34.36764
	

Inside for loop i=1:4

for each iteration eg: i=1

data1

    frame    par1         par2        par3    par4
    _____    ________    ________    ______    __

     1       268.13      143.89     25.376     1
     1       85.818      84.414     27.488     2
     1       173.56      165.74     28.634     3
     1        651.7      471.31     23.389     4
     1       678.37      317.05     32.631     5
     1       611.04      94.878     21.631     6
     1       451.42      353.31     26.549     7
     1       177.49      515.96     26.596     8
     1       287.63      367.65     29.248     9
     1        492.5      62.251     46.735    10
     

data2

    frame    par1           par2    par3       par4
    _____    ________    ________    ______    __

     2       265.99      141.51     25.046     1
     2        88.22      80.331     28.023     2
     2       174.12      168.28      28.08     3
     2       286.95      371.45     29.611     9
     2       681.29      322.52       33.3     5
     2       486.08      63.945     50.203    10
     2       614.1       96.111     21.493     6
     2       181.45      512.15     26.459     8
     2       648.41       474.4     25.315     4
     2       267.26       495.39     25.222    11
     2      393.29        249.04     29.059    12

now for i=1 i want to return data1 and dat2 to mat_bac, so that mat_bac has par4 included in it. likewise for i=2 ,3 ,4. my original table is much bigger than the mat_bac.

How can i do this?

Thank you

[Walter Roberson]

I suspect this should be combined with https://www.mathworks.com/matlabcentral/answers/476323-return-values-of-for-loop-to-a-table

[karishma koshy]

i thought it was deleted by me as the tables were not included. i have edited this question with points from previous version and have deleted the other version.

sorry for the confusion

Thank you

[dpb]

Not sure what data1 and data2 are but a table has to be regular in every variable must have the same number of rows. If you want to append a variable into an existing table, that's done easily-enough but you'll have to expand the size of the new variable(s) so their total length is the same as the height of the table.

[karishma koshy]

data_1 and data_2 for i=1 corresponds to frame 1 and 2 with extra column par4. i want mat_bac hav the new column. the desired out is

mat_bac=
   
frame par1 par2 par3 par4

so that its update for every iteration.

if it was same size, how can i do that?

Can please explain me with a code.

Thank you

[Image Analyst]

Have you looked at join()? Does that do what you want? Not exactly sure what you want to do. can you just do

mat_bac=[frame par1 par2 par3 par4];

[karishma koshy]

Yes i have gone through join(). that is not what i want.

for every iteration i want to sent the values of data1 and data2 to mat_bac with the exra column(par4), so its not overwritten. Right now, i get only the last iteration value result.

[Bob Thompson]

'Not sure what data1 and data2 are but a table has to be regular in every variable must have the same number of rows.'

You cannot replace portions of mat_bac with data1 or data2 because of the comment above by dpb. Before you can even consider making these replacements you need to add the fifth variable to mat_bac for ALL rows. I would suggest doing this by creating a variable of the appropriate size and then something like the following:

mat_bac = addvars(mat_bac,var4,'After','var3');

If you would like other ways to add variables to tables see this.

After the fifth column has been added the replacement of values should be relatively simple, just a matter of indexing.

'Right now, i get only the last iteration value result.'

This sounds like a very different issue, likely something due to indexing. We would need to see the related part of your code to give you a more specific idea of how to fix it.

Answer 1

[Pujitha Narra]

Hi Karishma,

You can extract the “par4” data from “data1” and “data2” and store it as a matrix. Further use this matrix to add the variable “par4” to the table “mat_bac”.

Extracting data as a matrix:

%initialization
par4=[];
%inside the loop
par4=[par4; data1.par4];
par4=[par4; data2.par4];

Adding the new variable to “mat_bac”:

mat_bac=addvars(mat_bac,par4);

You can look at these links for further information:

https://in.mathworks.com/help/matlab/matlab_prog/access-data-in-a-table.html

https://in.mathworks.com/help/matlab/matlab_prog/add-and-delete-table-variables.html