how to create a new variable based off an if else statement on one variable?

I have created a table in MATLAB, one of the variables is called animals. Within that coloum are "dogs", "cats", "sheep". I want to create code that states if table.animals == "dogs" then create a new variable called numbers and assign the number 1 to the rows that have dogs stated in it. If table.animals == "cats" then in that same new variable called numbers assign the number 2. and similar with sheep expect the number 3. How would I go about create this type of code?

This is something similar to what I have tried but it does not work.

if tables.animals == "Dogs"

tables.numbers = 1

elseif tables.animals == "cats"

tables.numbers = 2

else tables.numbers = 3

end

my code ends up usually create that new coloum but places the number 3 for all the rows.

Answer 1

[Voss]

t = table(["cats";"dogs";"cats";"sheep"],'VariableNames',"animals")

t = 4×1 table
    animals
    _______

    "cats" 
    "dogs" 
    "cats" 
    "sheep"

all_animals = ["dogs" "cats" "sheep"];
[~,idx] = ismember(t.animals,all_animals);
t.numbers = idx

t = 4×2 table
    animals    numbers
    _______    _______

    "cats"        2   
    "dogs"        1   
    "cats"        2   
    "sheep"       3   

[Elysia]

How were you able to assign the numbers to the animals? For example if I wanted to changes dogs to equal the number 38383 instead of 1, how would I change that?

[Voss]

The number was the index in "all_animals", since it was 1, 2, 3.

To be able to use arbitrary numbers instead, you can use those same indexes, but index into an array of the numbers you want (here I call it "all_numbers"):

t = table(["cats";"dogs";"cats";"sheep"],'VariableNames',"animals")

t = 4×1 table
    animals
    _______

    "cats" 
    "dogs" 
    "cats" 
    "sheep"

all_animals = ["dogs"; "cats"; "sheep"];
all_numbers = [38383;  29292;  10101];

[~,idx] = ismember(t.animals,all_animals);
t.numbers = all_numbers(idx)

t = 4×2 table
    animals    numbers
    _______    _______

    "cats"      29292 
    "dogs"      38383 
    "cats"      29292 
    "sheep"     10101 

[Elysia]

That makes so much sense! Thank you so much!

[Voss]

You're welcome!