I get the the error Attempted to access x(:,3); index out of bounds because size(x)=[5,2]. when trying to run the following code

TssinQf=[900 364;950 260;863 368;810 396;811 348]
Tssout=[224;200;396;260;208]
beta0=[0.21;0.2;0.12;0.33;0.1]
beta = nlinfit(TssinQf,Tssout,@hougen,beta0)

Answer 1

[Walter Roberson]

hougen Hougen-Watson model for reaction kinetics.
  YHAT = hougen(BETA,X) gives the predicted values of the
  reaction rate, YHAT, as a function of the vector of 
  parameters, BETA, and the matrix of data, X.
  BETA must have 5 elements and X must have three
  columns.

However your data only has 2 columns.