  Temperature, magnetic induction and substitution dependent resistivity are a
crucial factor in determining the physical properties of magneto-resistive
materials. The first objective of this work was to find out an applicable
method of using temperature to predict the resistivity of
Pr0.7(CaxSr1-x)0.3MnO3 in the metal phase within the transition area. Based on
non-linear curve fitting, a typical numerical method is used to quantitatively
analyze the temperature-dependent resistivity within temperatures lower than
the metal-insulator transition temperature (Tp). The simulations agree very
well with the observed curves (resistivity versus temperature). The second
objective of this work is to search for the applicable method to link
magneto-resistivity to magnetic induction, calculation on the principle of
non-linear curve fitting, four typical numerical methods are highlighted
because the magnetic induction-dependent magneto-resistivity are quantitatively
analyzed by these methods. The observed effects of magnetic induction on the
shift of temperature-resistive curve should be more essential in physics and
are quantitatively discussed in magneto-resistive materials. Lastly, the
influences of Ca substitution on magneto-resistivity are detected.
