本人初学matlab，急需解如下方程：
ms=tan(.42889e-1*y)-1.*((.19987e18*(tan(.53222e-1*y)+.11827*y)*(1.-1.*x^2)*(.59137e-2*y-1.*(1.+.30424e-1*y^2)*tan(.59137e-2*y))/(tan(.59137e-2*y)-.17741*y)-.10637e17*y+.19987e18*(1.+.20283e-1*y^2)*tan(.53222e-1*y))/(-78.121*y*tan(.53222e-1*y)*(1.-1.*x^2)*(.59137e-2*y-1.*(1.+.30424e-1*y^2)*tan(.59137e-2*y))/(tan(.59137e-2*y)-.17741*y)-78.121*y*(tan(.53222e-1*y)-.17149*y))+.86560e15*tan(.57856e-1*y))/((.35827e18*(tan(.53222e-1*y)+.11827*y)*(1.-1.*x^2)*(.59137e-2*y-1.*(1.+.30424e-1*y^2)*tan(.59137e-2*y))/(tan(.59137e-2*y)-.17741*y)-.19067e17*y+.35827e18*(1.+.20283e-1*y^2)*tan(.53222e-1*y))/(-78.121*y*tan(.53222e-1*y)*(1.-1.*x^2)*(.59137e-2*y-1.*(1.+.30424e-1*y^2)*tan(.59137e-2*y))/(tan(.59137e-2*y)-.17741*y)-78.121*y*(tan(.53222e-1*y)-.17149*y))*tan(.57856e-1*y)-.48290e15)
已知方程ms，其中的未知数为x y ，现要找y随x的变化曲线，x在0.1:0.9内变化。希望哪位大侠能够帮帮忙，急需详细程序感激不尽！

>> ezplot('tan(.42889e-1*y)-1.*((.19987e18*(tan(.53222e-1*y)+.11827*y)*(1.-1.*x^2)*(.59137e-2*y-1.*(1.+.30424e-1*y^2)*tan(.59137e-2*y))/(tan(.59137e-2*y)-.17741*y)-.10637e17*y+.19987e18*(1.+.20283e-1*y^2)*tan(.53222e-1*y))/(-78.121*y*tan(.53222e-1*y)*(1.-1.*x^2)*(.59137e-2*y-1.*(1.+.30424e-1*y^2)*tan(.59137e-2*y))/(tan(.59137e-2*y)-.17741*y)-78.121*y*(tan(.53222e-1*y)-.17149*y))+.86560e15*tan(.57856e-1*y))/((.35827e18*(tan(.53222e-1*y)+.11827*y)*(1.-1.*x^2)*(.59137e-2*y-1.*(1.+.30424e-1*y^2)*tan(.59137e-2*y))/(tan(.59137e-2*y)-.17741*y)-.19067e17*y+.35827e18*(1.+.20283e-1*y^2)*tan(.53222e-1*y))/(-78.121*y*tan(.53222e-1*y)*(1.-1.*x^2)*(.59137e-2*y-1.*(1.+.30424e-1*y^2)*tan(.59137e-2*y))/(tan(.59137e-2*y)-.17741*y)-78.121*y*(tan(.53222e-1*y)-.17149*y))*tan(.57856e-1*y)-.48290e15)-0.1');
>>

这个函数是从哪里来的？
能否告知一下？