function i_ppp = ppp_ippp (n_ppp,sympar,sympars)
## usage: i_ppp = ppp_ippp (n_ppp,sympar,sympars)
## nppp number of ppp parameters
## sympar symbolic parameter structure for system
## sympar symbolic parameter structure for sensitivity system
## Returns a matrix i_ppp with n_ppp rows and 3 columns
## First col: index of ith ppp parameter of sensitivity system
## Second col: index of ith ppp sensitivity parameter of sensitivity system
## Third col : index of ith ppp sensitivity parameter of system
## Copyright (C) 2002 by Peter J. Gawthrop
i_ppp = [];
for i=1:n_ppp
i_ppp_i = eval(sprintf("[sympars.ppp_%i, sympars.ppp_%is \
sympar.ppp_%i];",i,i,i));
i_ppp = [i_ppp ; i_ppp_i];
endfor
endfunction