Cantera nAtoms function error

I want to use nAtoms function for my project, but it seems to be malfunctioning. I can't find the reason. I'm currently using R2020b version.

It gives a value of -1, no matter the species or atom I put in.What's the problem?

[John D'Errico]

which IdealGasMix -all

'IdealGasMix' not found.

which nAtoms -all

'nAtoms' not found.

These do not seem to be part of MATLAB, nor are they in any toolbox. (I don't know what is cantera.) But it would seem you need to read the tutorials for that set of tools.

https://cantera.org/tutorials/matlab-tutorial.html

[Jun Seok Song]

Its part of cantera toolbox, thermophases.