Exporting data to excel every time a program is run

I want to be able to write data to an excel spreadsheet after running a program. I know how to do this once, but I want to be able to run the program many times and add the data to excel each time, without overwriting the previous data in the spread sheet. For example:

a = x^2;

If I run this for x=1, I can get my answer and export it to excel ok. But if I run the exact same program again for x=2, I want it to write the answer to the same spreadsheet as the first one without overwriting the original data. My program is much more complex than this obviously but I want to get a general sense of how it's done.

I would prefer methods that don't involve any loops.

Answer 1

[ChristianW]

x = 1:100;
a = x.^2;
xlswrite('xls_test',a)

Answer 2

[Srinivas]

look for the sheet and range options in xlswrite

'I want it to write the answer to the same spreadsheet as the first one without overwriting the original data' what does this mean, you want to shift the previous output downwards.