p == p_rgh + rhogh or p = p_rgh+rhogh

wouter · February 23, 2011, 18:55

Dear All,

My c++ is rusty so here the question:
in pEqn.H there is a statement:
p== p_rgh + rho*gh;
To my knowledge this gives true or false, but it is not assigned to anything.
It is an empty statement unless == is redefined somewhere (where?).
But why is a few lines down p_rgh = p - rho*gh; and not p_rgh == p-rho*gh;

OF170 and OF171

nimasam · February 24, 2011, 04:52

i guess!
== isnot equality here, it assigns all domains include boundary condition from left side to right side!!!!
but = just copy internalField values!

Bernhard · February 24, 2011, 05:11

Maybe this thread is helpfull
http://www.cfd-online.com/Forums/ope...-operator.html

wouter · February 24, 2011, 08:27

Sorry I did not find this thread, but thanks.

Best
Wouter

February 23, 2011, 18:55	*p == p_rgh + rhogh or p = p_rgh+rhogh*	#1
wouter Senior Member Wouter van der Meer Join Date: May 2009 Location: Elahuizen, Netherlands Posts: 203 Rep Power: 18	Dear All, My c++ is rusty so here the question: in pEqn.H there is a statement: p== p_rgh + rhogh; To my knowledge this gives true or false, but it is not assigned to anything. It is an empty statement unless == is redefined somewhere (where?). But why is a few lines down p_rgh = p - rhogh; and not p_rgh == p-rho*gh; OF170 and OF171

February 24, 2011, 08:27	thanks	#4
wouter Senior Member Wouter van der Meer Join Date: May 2009 Location: Elahuizen, Netherlands Posts: 203 Rep Power: 18	Sorry I did not find this thread, but thanks. Best Wouter

February 24, 2011, 04:52		#2
nimasam Senior Member Nima Samkhaniani Join Date: Sep 2009 Location: Tehran, Iran Posts: 1,267 Blog Entries: 1 Rep Power: 25	i guess! == isnot equality here, it assigns all domains include boundary condition from left side to right side!!!! but = just copy internalField values!

February 24, 2011, 05:11		#3
Bernhard Senior Member Bernhard Join Date: Sep 2009 Location: Delft Posts: 790 Rep Power: 22	Maybe this thread is helpfull http://www.cfd-online.com/Forums/ope...-operator.html

p == p_rgh + rho*gh or p = p_rgh+rho*gh

p == p_rgh + rhogh or p = p_rgh+rhogh