How to performing global fit with dataplot

[Marcin Sarewicz <marcin@biotka.mol.uj.edu.pl>]

Hello

I wonder if it it possible to perform global analysis fit to several
data sets simultaneously. For example a want to fit double exponential
function to my datapoints with local variable being proportions of the
exponent, and global parameters being time constants (t1, t2):

    Y0=a0*exp(-X0/t1) + b0*exp(-X0/t2)
    Y1=a1*exp(-X1/t1)+b1*exp(-X1/t2)
    .............................
    Yn=an*exp(-Xn/t1)+bn*exp(-Xn/t2)

Variables: a0, b0, a1, b1 ... an, bn, are local variables to fit that
changes from function to function, and t1 t2 are variables to fit that
are constant for all functions.
Is dataplot capable to perform such global fit?

Thanks
Marcin Sarewicz