assume() command with functions

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The assume function doesn't work with symbolic functions.

I think the command assume(Q>0) should raise an exception (it doesn't right now obviously). If you look at the documentation for assume you'll see that all the examples involve symbolic variables only.

On the other hand, the type of Q in your example is sage.symbolic.expression.Expression so maybe this is supposed to work and you've found a bug. I'll dig deeper and see what I can find.

I guess my problem is related to this one:

var('Nr N1 N2 yr x1 x2 y2 Pr p0 P1 p2')
assume(N1>0, N2>0, Nr>0, Pr>0, p0>0, p2>0, p0+p2-1<0);
assume(P1-Nr*p2+p2-Nr*p0+p0+Nr-1>0)
h1 = 1/sqrt(2*pi*Nr)*exp(-(yr-(x1+x2))^2/(2*Nr))/sqrt(2*pi*N2)*exp(-(y2-sqrt(Pr/((1-p0)(Nr+P1/(1-p0-p2))))*yr)^2/(2*N2))*(y2-sqrt(Pr/((1-p0)(Nr+P1/(1-p0-p2))))*yr)/Nr*sqrt(Pr/((1-p0)*(Nr+P1/(1-p0-p2))))*yr*(1/(2*(1-p0))-P1/(2*(1-p0-p2)^2*(P1/(1-p0-p2)+Nr)))+1/sqrt(2*pi*N2)*exp(-(y2-sqrt(Pr/((1-p0)(Nr+P1/(1-p0-p2))))*yr)^2/(2*N2))/sqrt(2*pi*Nr)*exp(-(yr-(x1+x2))^2/(2*Nr))*(yr-(x1+x2))/Nr*x1^3/(2*P1); h1
h2 = 1/2*h1(x2=0,x1=sqrt(P1/(1-p0-p2)))+1/2*h1(x2=0,x1=-sqrt(P1/(1-p0-p2))); h2
py2x1x2 = integrate(h2,yr,-oo,oo); py2x1x2
Traceback (click to the left of this block for traceback)
...
Is  p2+p0-1  positive or negative?

The important parts are

assume(p0+p2-1<0);

and

Is  p2+p0-1  positive or negative?

obviously. Did I get you right, this is not supposed to work?

Thank you