Clear Filters
Clear Filters

How can you create an empty table object with named columns?

116 views (last 30 days)
How can you create an empty table object with named columns?
I have a loop that logically does something like this:
a = 1
b = 2
t = [t; table(a, b)]
a = 5
b = 6
t = [t; table(a, b)]
However, I want to add an assert after each row creation, like this:
a = 1
b = 2
t = [t; table(a, b)]
assert(0 == sum(t{:,{'a'}} == t{:,{'b'}}))
a = 5
b = 6
t = [t; table(a, b)]
assert(0 == sum(t{:,{'a'}} == t{:,{'b'}}))
But since t starts off empty, before I run t{:,{'a'}} I have to check if t is empty. I imagine if I can have named columns in an empty table, the problem can be solved?

Answers (1)

Nikita Agrawal
Nikita Agrawal on 7 Jan 2021
  3 Comments
Nikita Agrawal
Nikita Agrawal on 7 Jan 2021
You can keep data empty. Here you go:
Headers = {'A','B'}
Empty_table = cell2table(cell(1,2),'VariableNames'= Headers)
Stephen23
Stephen23 on 7 Jan 2021
Edited: Stephen23 on 7 Jan 2021
@Nikita Agrawal: sure. But the original question asked about an empty table, not empty data.
To make an empty table, the input cell array must be empty too:
Headers = {'A','B'}
Headers = 1x2 cell array
{'A'} {'B'}
Empty_table = cell2table(cell(0,2),'VariableNames', Headers)
Empty_table = 0x2 empty table
Empty_table.Properties.VariableNames
ans = 1x2 cell array
{'A'} {'B'}

Sign in to comment.

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!