# Illegal kernel in adjoin pvar

 1 I tried running a seemingly simple script involving a Fourier transform in a sage notebook var('A, x, delta, k, dx, t, v, xi') temp = A*exp(-(x/delta)^2) temp = integral(temp*exp(-I*k*x),(x,-oo,oo)).simplify() (delta>0).assume() (k>0).assume() (dx>0).assume() (xi<1).assume() temp = temp*exp(-I*k*t*v)*exp(-(k^2)*t*v*dx*(1-xi)/2) temp = integral(temp*exp(I*k*x)/(2*pi),(k,-oo,oo))  and I got the following error message Condition of type: SIMPLE-CONDITION Illegal kernel in adjoin-pvar' Available restarts: 1. (CONTINUE) Return from BREAK. Top level. >  Any idea what's going on? asked Mar 01 '13 bolverk 65 ● 6 kcrisman 7802 ● 20 ● 78 ● 170

 2 This can be slightly simplified to var('A, x, delta, k, dx, t, v, xi') temp = 1/2*A*e^(1/2*(xi - 1)*dx*k^2*t*v - 1/4*delta^2*k^2 - I*k*t*v + I*k*x)/(sqrt(pi)*sqrt(delta^(-2))) integral(temp,(k,0,oo)) ` with the same error. So the assumptions are not the cause. In fact, it is a Maxima error. I've reported this upstream at Maxima bug 2556. posted Mar 01 '13 kcrisman 7802 ● 20 ● 78 ● 170