Hi there, I got a set of discrete Data as functions of 4 variables (x1,x2,x3,x4) . I would like to interpolate the data with respect to x2 and then get a continuous function f (x1,x2,x3,x4). Finally I would like to get the partial derivative of f wrt x2. How can I sort this out? x has the range [0,x0]. s is an arbitrary function of x. g is a function of (x1,x2,x3,x4) which is formed from solving the IVP numerically. x0:= 1/2: s:=x->x^2: sol:=(x2,x3,x4)->dsolve({y''(x1)-(x3^2+s(x1)*x4^2)*y(x1)=0,y(x2)=exp(-x2),y'(x2)=1/2},numeric,output=operator,range=0..x0):

Hi there, I got a set of discrete Data as functions of 4 variables (x1,x2,x3,x4) . I would like to interpolate the data and then get a continuous function f in terms of (x1,x2,x3,x4). Finally I would like to get the partial derivative of f wrt x2. How can I sort out this? x0:= 1/2: s:=x->x^2: sol:=(x2,x3,x4)->dsolve({y''(x1)-(x3^2+s(x1)*x4^2)*y(x1)=0,y(x2)=exp(-x2),y'(x2)=1/2},numeric,output=operator,range=0..x0): g:=(x1,x2,x3,x4)->eval(y(x1),sol(x2,x3,x4)): g(x0/3,x0/3,10,1); dx2:=1/1000: Data:=(x1,x2,x3,x4)->[seq([x2+i*dx2,g(x1,x2+i*dx2,x3,x4)],i=-3..3)]: ???

I got an expression: R:=(2*E-2*sqrt(E)*sqrt(E-V0)-V0)/(sqrt(E)+sqrt(E-V0))^2; I would like to plot R as a function of E/V0. I tried to substitute E=mu*V0 to R, then plot(R,mu=0.1..1),but failed to get the plot. How can I get the right figure? thanks.

I got an expression f:=R^3/(z^2+R^2)^(3/2); and would like to plot f as a function of (z/R), not z. Here R is a parameter. Could someone give me a hand?