How to include a new fixed string ('Name') on header and numerical variable (subsequent rows) in a new column, at the beggining, of a existing .csv file?

My data.csv file, contains a header with variable names with two different variable types (string and double), as follows:

Region,Num1,Num2,Num3...,

1 and 2,324,0.32054,0.98517,...,

1 or 2,558,0.76092,0.91255,...,

.

.

.

I want to create a new column with the Identification on the header (string ID), and in the subsequent rows the Identification Number (for all value rows), that it is the variable that I must pass the value. I want something like this:

ID,Region,Num1,Num2,Num3...,

1314,1 and 2,324,0.32054,0.98517,...,

1314,1 or 2,558,0.76092,0.91255,...,

.

.

.

How can I start solving this?

Answer 1

[Voss]

% show the contents of data.csv
type data.csv

Region,Num1,Num2,Num3
1 and 2,324,0.32054,0.98517
1 or 2,558,0.76092,0.91255

% the IDs you want to include in the file:
IDs = [1314; 1314];

% read the file
C = readcell('data.csv');
% prepend the ID column
C = [['ID'; num2cell(IDs(:))] C];
% write the result
writecell(C,'data_new.csv');

% show the contents of data_new.csv
type data_new.csv

ID,Region,Num1,Num2,Num3
1314,1 and 2,324,0.32054,0.98517
1314,1 or 2,558,0.76092,0.91255