Merge table with different rows

I have two files with different rows but with the same number of columns and I want to combine it together but I am getting an error * All tables in the bracketed expression must have the same number of rows. *

file1 = readtable('306K-268K.csv'); file2 = readtable('266K-228K.csv'); Com = [file1 file2];

Thanks a lot for the help

Answer 1

[Star Strider]

You probably want the outerjoin (link) function:

Com = outerjoin(file1,file2);

See if that does what you want.

[Shelender Kumar]

Thanks but it is adding extra NAN in each row

[Star Strider]

The outerjoin function has additional arguments that you can use that could provide the result you want. It appears to be the only one of that group of functions that is compatible with your data.

[MattyK]

Thanks very much for this solution, have always wanted it. It works perfectly

[Star Strider]

@MattyK — My pleasure!

Answer 2

[madhan ravi]

You can't merge table with different number of size dimensions , use structure instead

[Shelender Kumar]

thanks, let us say I have two sets A and B which looks like this

A =

1.38E-01  -1.02E-05  -8.81E-02  
1.54E-01  NaN  -5.51E-02  
6.41E+01  7.83E-06  1.09E+02  

B =

1.38E-01  -1.02E-05  -8.81E-02  
1.54E-01  NaN  -5.51E-02  

answer=

here A and B are side by side

1.38E-01  -1.02E-05  -8.81E-02  1.38E-01  -1.02E-05  -8.81E-02 
1.54E-01  NaN  -5.51E-02      1.54E-01  NaN  -5.51E-02  
6.41E+01  7.83E-06  1.09E+02  

[madhan ravi]

A = [1.38E-01  -1.02E-05  -8.81E-02  
1.54E-01  NaN  -5.51E-02  
6.41E+01  7.83E-06  1.09E+02  ]

B = [1.38E-01  -1.02E-05  -8.81E-02  
1.54E-01  NaN  -5.51E-02 ;
zeros(1,size(A,2))] %PADDED WITH ZEROS because matrix dimensions should be the same when concatenated
 
side_by_side=[A B]

[Shelender Kumar]

Thanks a lot, I made a mistake in asking question to you, actually A and B are csv file. for example if you follow thread on the top, you will find that I have attched two files

file1 = readtable('306K-268K.csv'); 
file2 = readtable('266K-228K.csv');

I wanted to combine file1 (dim is 642*40) and file2(681*40)

Thanks

[madhan ravi]

file1 = readtable('306K-268K.csv'); 
file2 = readtable('266K-228K.csv');
A=table2array(file1);
B=table2array(file2);
size(A)
size(B)
A=[A;zeros(size(B,1)-size(A,1),size(B,2))];
side_by_side = [A B]

size(side_by_side) %should be 681*80 if it is then we have achieved it

[Shelender Kumar]

Thanks, but I was thinking more of a genral solution, because I have 7 files like this, all of which have a differnt rows but the number of coloumns are same.

[madhan ravi]

A=[A;zeros(abs(size(B,1)-size(A,1)),size(B,2))];

[Shelender Kumar]

Thanks a lot

[madhan ravi]

Glad to help :)

Answer 3

[Stéphane Rainville]

You're missing a semi-colon to invoke vertical concatenation ('vertcat') rather than default horizontal concatenation ('horzcat').

For instance, two tables with different number of rows (but same number of columns), this does NOT work:

myBigTable = [myTable1 myTable2];
But this does:
myBigTable = [myTable1; myTable2];
I was facing a similar problem when storing tables of different lengths in a cell array.
myTables{1} = myTable1;
myTables{2} = myTable2;
and using
bigTable = [myTables{:}] 

did not work because unwrapping and concatenating cell contents invoked horizontal concatenation. You can't just stick a semi-colon in there, so I had to explicitly invoke vertical concatenation like this:

bigTable = vertcat(myTables{:});

[Shelender Kumar]

Thanks for the help

but I want to place my file1 and file2 side by side. That means it should give me the data like horizcat

[Stéphane Rainville]

Ah I see. Then yeah, tables of different length would be a problem.

Answer 4

[the cyclist]

I'm guessing you need the join command.

[Shelender Kumar]

I have some NAN values in my column so I am getting this error The key variables for A and B cannot contain any missing values.

Answer 5

[Peter Perkins]

"Merge" is kind of vague. It may be that you just need to add a semicolon to vertically concatenate:

Com = [file1; file2]

[Shelender Kumar]

Thanks a lot but I want to place to data side by side not above and below

[HabenG]

Have you figured out the issues?? seems like there is no way to simply combine columns of different size matrrix, table, array etc...i feel like there should be a simple fuction for this

[Peter Perkins]

The current way to do this is to create the same number of rows in the smaller matrix/table/whatever. That's already been shown in an earlier reply.