@tomleslie 
Great!
Tahnks a lot!

@Rouben Rostamian  
Thank you very much

@Preben Alsholm 
Thanks for your comprehensive comments.
If:
V:=-n^2*((T[e]+T[i])/T[e])*((((n)*(1+1/(2*delta[p]))))-ln(n)-ln(n/(2*delta[p]))-1-1/(4*delta[p])-delta[p]);
Can I expect to come up with an answer similar to soliton waves?
How can I plot the curves for different values of delta[p] in the same frame?(for example, delta[p]=0.7,0.9)

 

@Preben Alsholm

Thanks.

You are right about giving up the IC. 

If I change the IC(s) to n(x)=0 when x=+/- infinity, what happen for curves corresponding to d[p] =0.2, 0.25? 

@Preben Alsholm 

Great!!
How I can delete the shift of curves toward the RHS in such a way that the maximum of all curves locate on the y axis(n(x))?

@Preben Alsholm 
Thank you.
I try to plot RES1 for two different deta[p], namely 0.2, 0.25, by -display command, but I cauldn't. How can I do this?
 

@mary120 
Hi,

I tried to plot the real and imaginary parts of a new parametric function, but I coulnd't. May you please help me.

I want to extract Re(x) and Im(x) vs y1 from the assumed eqaution and then plot Re(x) and Im(x) vs y1 for z=0.001, 0.002, 0.003 and r=0.1, 0.2, 0.3.

Re-Im.mw

@mmcdara 
Thank you very much !

@Carl Love 

#   How to solve the following set of nonlinear equations and plot variation of u[i01],u[i02] and phi[d0] versus delta[d] for alpha=0.01,delta[d]=1e-4? 
#
#

restart;
Eq1:=1.359375000*10^36*delta[d]*phi[d0]-delta[e]+delta[i]+1 = 0:

Eq2:=7.217742610*10^14*u[i10]*(1-2*phi[d0]/u[i10]^2)+2.282450621*10^15*delta[i]*u[i20]*(1-2*phi[d0]/u[i20]^2)-2.206601886*10^17*sqrt(2)*delta[e]*(4*alpha*phi[d0]^2/(3*alpha+1)-16*alpha*phi[d0]/(3*alpha+1)+(24*alpha+1)*exp(phi[d0])/(3*alpha+1)) = 0:

Eq3:=5.882341298*10^8*u[i10]^2+1.203367844*10^9*delta[e]/u[i10]-8.823511948*10^7*u[i20]^2-9.633614643*10^7*delta[e]/(delta[i]*u[i20]) = 0:

Eq4:=2.406735687*10^10*delta[e]/u[i10]+9.633614644*10^8*delta[e]/u[i20]-(delta[e]*(4*alpha/(3*alpha+1)-1)+1.510416667*10^37*delta[d]*phi[d0]^2)*(5.882341298*10^8*u[i10]^2+1.203367844*10^9*delta[e]/u[i10])-1.359375000*10^36*delta[d]*phi[d0]*((1.157401021*10^(-25)*Pi)*u[i10]*sqrt(u[i10]^2+8/Pi)*(1-2*phi[d0]/(u[i10]^2+0.4244131815e-1))^1.0+1.395921345*10^(-54)*u[i10]*sqrt(u[i10]^2+8/Pi)*phi[d0]^2*ln((phi[d0]^2/(1000000000000*(u[i10]^2+0.4244131815e-1)^2)+2.005078125*10^14/(1+0.1666666667e-1*delta[e]+.5000000000*delta[i])^1.0)/(phi[d0]^2/(1000000000000*(u[i10]^2+0.4244131815e-1)^2)+(1/1000000000000)*(1-2*phi[d0]/(u[i10]^2+0.4244131815e-1))^1.0))/(u[i10]^2+0.4244131815e-1)^2+(1.157401021*10^(-25)*Pi)*delta[i]*u[i20]*sqrt(u[i20]^2+8/Pi)*(1-2*phi[d0]/(u[i20]^2+0.8488263632e-1))^1.0+1.395921345*10^(-55)*delta[i]*u[i20]*sqrt(u[i20]^2+8/Pi)*phi[d0]^2*ln((phi[d0]^2/(1000000000000*(u[i20]^2+0.8488263632e-1)^2)+2.005078125*10^14/(1+0.1666666667e-1*delta[e]+.5000000000*delta[i])^1.0)/(phi[d0]^2/(1000000000000*(u[i20]^2+0.8488263632e-1)^2)+(1/1000000000000)*(1-2*phi[d0]/(u[i20]^2+0.8488263632e-1))^1.0))/(u[i20]^2+0.8488263632e-1)^2-4.484955822*10^(-6))+6.240139645*10^(-20)*delta[d]*(7.217742610*10^14*u[i10]*(1-2*phi[d0]/u[i10]^2)+2.282450621*10^15*delta[i]*u[i20]*(1-2*phi[d0]/u[i20]^2)-2.206601886*10^17*sqrt(2)*delta[e]*(4*alpha*phi[d0]^2/(3*alpha+1)-16*alpha*phi[d0]/(3*alpha+1)+(24*alpha+1)*exp(phi[d0])/(3*alpha+1))) = 0:

@acer 
Thanks for your reply. 
Please, see the attached file.
q.mw

@acer 
How can I insert a legend like "n_{0p}/n_{0n}=0.1" in above graph? How can I change the legend font size?
Thanks

@tomleslie 
Thanks for your help.
But, there was an error when I run the code (see below)!
I want to export (x,U1(x)) as a two-column .txt or .dat file.
About my third question, I look for a command like " if U1(x)>20, then exit" that stop the code for a specific condition!

q.mw

@acer 

Yes, I want to export the numeric data as a two-column txt file ( X, U1(x)). I need a command like " write(1,*) x, U1(x)" in fortran.

Hi,

I have 3 questions and I hope you  help me:

1- How can I extract the numerical data of (x,U1) to use it in another software such as Origin?
2- What is your suggestion to plot the curves of, for example, (x,U1) for different parameters (T,k,beta) in one figure? How can I do that?
I need to do it for comparing the effects of different values of parameters.

3- How can I stop the numerical calculation when U1(x)>20 ?

@Carl Love 
Thank you for your reply.