a way to find out wall-neighboring cells?

May 8, 2002, 06:52

hello!

i want to find out the cell-ID of all wall-neighboring cells and declare them as a variable. I have written the following UDF, but I don't know how to find out if it works, because i have no idea how to view the cell-ID or the cells.

#include "udf.h" #include "mem.h"

cell_t c; cell_t c0; cell_t c1; face_t f; Domain *domain; Thread *t;

DEFINE_ON_DEMAND(cell_check) { begin_f_loop(f, t)

{

cell_t c0 = F_C0(f, t);

if (c0 == NULL)

{

cell_t c1 = F_C1(f, t);

}

} end_f_loop(f, t) }

1. Does anybody know how i can check if it works? 2. Maybe you know that it won't work and have other proposals, please tell me!

Thanks in advance, Christian

May 8, 2002, 22:46

Why not work? It seems perfect!!!

The way to test it is to try cases... lol

May 9, 2002, 05:55

tested it ==> segmentation violation. I knew it seemed perfect, but that`s the way perfect things work. I can imagine there is an error produced at the inlet/outlet boundary conditions. by the way, the command `NULL`is defined in FLUENT anyway?

Christian

May 9, 2002, 06:59

<html> <body>
Have you defined the thread var f globally? Sounds you like global definition...lol

If not or f is not assigned correctly, there must be a problem with your function, DEFINE_ON_DEMAND(cell_check). "segmentation violation" means you are refering an mem address out of the stack or heap, and this suggest you an easy way to debug it: try to test the value of the pointer var. Since there is no debugger in Fluent, some printf statements may help.

NULL is OK, since it's an internal macro of C compiler defined in, for example, stdio.h. If you are still not sure about it, you can use if((ulong)c0==0)...

Enjoy your debugging~~~

<font size=5 face=script color=#0000FF>Johnix</font>

</body> </html>

May 10, 2002, 09:30

Thanks a lot, Johnix!

May 8, 2002, 06:52	a way to find out wall-neighboring cells?	#1
Christian Guest Posts: n/a	hello! i want to find out the cell-ID of all wall-neighboring cells and declare them as a variable. I have written the following UDF, but I don't know how to find out if it works, because i have no idea how to view the cell-ID or the cells. #include "udf.h" #include "mem.h" cell_t c; cell_t c0; cell_t c1; face_t f; Domain domain; Thread t; DEFINE_ON_DEMAND(cell_check) { begin_f_loop(f, t) { cell_t c0 = F_C0(f, t); if (c0 == NULL) { cell_t c1 = F_C1(f, t); } } end_f_loop(f, t) } 1. Does anybody know how i can check if it works? 2. Maybe you know that it won't work and have other proposals, please tell me! Thanks in advance, Christian

May 8, 2002, 22:46	Re: a way to find out wall-neighboring cells?	#2
Johnix Guest Posts: n/a	Why not work? It seems perfect!!! The way to test it is to try cases... lol

May 9, 2002, 05:55	Re: a way to find out wall-neighboring cells?	#3
Christian Guest Posts: n/a	tested it ==> segmentation violation. I knew it seemed perfect, but that`s the way perfect things work. I can imagine there is an error produced at the inlet/outlet boundary conditions. by the way, the command `NULL`is defined in FLUENT anyway? Christian

May 9, 2002, 06:59	Re: a way to find out wall-neighboring cells?	#4
Johnix Guest Posts: n/a	<html> <body> Have you defined the thread var f globally? Sounds you like global definition...lol If not or f is not assigned correctly, there must be a problem with your function, DEFINE_ON_DEMAND(cell_check). "segmentation violation" means you are refering an mem address out of the stack or heap, and this suggest you an easy way to debug it: try to test the value of the pointer var. Since there is no debugger in Fluent, some printf statements may help. NULL is OK, since it's an internal macro of C compiler defined in, for example, stdio.h. If you are still not sure about it, you can use if((ulong)c0==0)... Enjoy your debugging~~~ <font size=5 face=script color=#0000FF>Johnix</font> </body> </html>

May 10, 2002, 09:30	Re: a way to find out wall-neighboring cells?	#5
Christian Guest Posts: n/a	Thanks a lot, Johnix!

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