How to solve a function with different ranges

I have a variable that is composed of two functions for different ranges:

alfa_ox = 1/15*C_ox for 0 <= C_ox <= 15

alfa_ox = 1 for C_ox > 15

When I imply this in Matlab, it doesnt consider the second condition (that alfa can't be bigger than 1). How can I solve that?

C_ox = [16;15;7.5;2;7.5;15;15];
if C_ox > 15                                    
   alfa = 1
else alfa = 1/15.*C_02
end  


Output:
alfa =

    1.0667
    1.0000
    0.5000
    0.1333
    0.5000
    1.0000
    1.0000

[Scott MacKenzie]

What is C_02?

[Delia Bosshart]

It is the oxygen concentration so in this context also a varibale

[Scott MacKenzie]

Is it a vector? It might help if you provide the data.

[Scott MacKenzie]

And BTW, your if-expression is an array. That's probably not what is itended.

[Delia Bosshart]

Yes it is a vector. I could already solve the problem with the answers provided, thank you.

[Scott MacKenzie]

Sorry for the string of comments here, but your question uses the expression

1/15*C_ox

In your code we see

1/15.*C_02

Please clarify.

Answer 1

[Star Strider]

alfa_fcn = @(C_ox) min(C_ox/15,1);

C_ox = [16;15;7.5;2;7.5;15;15];

alfa = alfa_fcn(C_ox)

alfa = 7×1

1.0000 1.0000 0.5000 0.1333 0.5000 1.0000 1.0000

.

[Delia Bosshart]

Thank you!

Answer 2

[Alan Stevens]

Try

C_ox = [16;15;7.5;2;7.5;15;15];
C_ox(C_ox<=15)=C_ox(C_ox<=15)/15;
C_ox(C_ox>15)=1

C_ox = 7×1

1.0000 1.0000 0.5000 0.1333 0.5000 1.0000 1.0000