If scheme doesn't work

p.1 · November 30, 2020, 15:37

Hi, I have write this udf but the if statement seems not work. Someone can help me?

#include "udf.h"

DEFINE_ADJUST(dudy, domain)
{
Thread *t;
cell_t c;
real xc[ND_ND];
real x;
real y;

thread_loop_c(t, domain)
{
begin_c_loop(c, t)
{
C_CENTROID(xc, c, t);
x = xc[0];
y = xc[1];
if(y < 0 && x<6)
{
C_UDMI(c, t, 0) = -(C_V(c, t)*C_U_G(c, t)[1])
}

else if(y<0 && x>6)
{

C_UDMI(c, t, 0) = -(C_V(c, t)*-C_U_G(c, t)[1])
}

else if(y>0 && x<6)
{

C_UDMI(c, t, 0) = -(-C_V(c, t)*C_U_G(c, t)[1])
}

else if(y>0 && x>6)
{

C_UDMI(c, t, 0) = -(-C_V(c, t)*-C_U_G(c, t)[1])
}

}
end_c_loop(c, t)
}
}

AlexanderZ · November 30, 2020, 22:10

how could you know that it doesnt work?

p.1 · December 1, 2020, 03:28

Quote:

Originally Posted by AlexanderZ

how could you know that it doesnt work?

Beacuse if I change the x value (for example x<10 or x>10) the results are the same.

pakk · December 1, 2020, 03:41

Try this, to see if it works:

Code:

DEFINE_ADJUST(dudy, domain)
{
Thread *t;
cell_t c;
real xc[ND_ND];
real x;
real y;

thread_loop_c(t, domain)
{
begin_c_loop(c, t)
{
C_CENTROID(xc, c, t);
x = xc[0];
y = xc[1];
if(y < 0 && x<6)
{
C_UDMI(c, t, 0) = 1;
}

else if(y<0 && x>6)
{

C_UDMI(c, t, 0) = 2;
}

else if(y>0 && x<6)
{

C_UDMI(c, t, 0) = 3;
}

else if(y>0 && x>6)
{
C_UDMI(c, t, 0) = 4;
}

}
end_c_loop(c, t)
}
}

By the way: are you sure you did not get any compile error? Because I think you forgot some semicolons, and the compiler should complain about that.

p.1 · December 1, 2020, 03:52

Quote:

Originally Posted by pakk

Try this, to see if it works:

Code:

DEFINE_ADJUST(dudy, domain)
{
Thread *t;
cell_t c;
real xc[ND_ND];
real x;
real y;

thread_loop_c(t, domain)
{
begin_c_loop(c, t)
{
C_CENTROID(xc, c, t);
x = xc[0];
y = xc[1];
if(y < 0 && x<6)
{
C_UDMI(c, t, 0) = 1;
}

else if(y<0 && x>6)
{

C_UDMI(c, t, 0) = 2;
}

else if(y>0 && x<6)
{

C_UDMI(c, t, 0) = 3;
}

else if(y>0 && x>6)
{
C_UDMI(c, t, 0) = 4;
}

}
end_c_loop(c, t)
}
}

By the way: are you sure you did not get any compile error? Because I think you forgot some semicolons, and the compiler should complain about that.

Thank you, no when I compile the UDF on Fluent there aren't errors.
Where I forgot some semicolons?

pakk · December 1, 2020, 13:38

You forgot semicolons where i changed the code, obviously.

You also forgot to show the test result. How does UDM 0 look like if you plot with this UDF?

pakk · December 1, 2020, 13:40

And does this give errors?

Code:

DEFINE_ADJUST(dudy, domain)
{
Thisshouldgiveanerror() ;
}

p.1 · December 1, 2020, 13:57

Quote:

Originally Posted by pakk

You forgot semicolons where i changed the code, obviously.

You also forgot to show the test result. How does UDM 0 look like if you plot with this UDF?

It works. Thank you.

November 30, 2020, 15:37	If scheme doesn't work	#1
p.1 New Member Italia Join Date: Oct 2020 Posts: 19 Rep Power: 6	Hi, I have write this udf but the if statement seems not work. Someone can help me? #include "udf.h" DEFINE_ADJUST(dudy, domain) { Thread t; cell_t c; real xc[ND_ND]; real x; real y; thread_loop_c(t, domain) { begin_c_loop(c, t) { C_CENTROID(xc, c, t); x = xc[0]; y = xc[1]; if(y < 0 && x<6) { C_UDMI(c, t, 0) = -(C_V(c, t)C_U_G(c, t)[1]) } else if(y<0 && x>6) { C_UDMI(c, t, 0) = -(C_V(c, t)-C_U_G(c, t)[1]) } else if(y>0 && x<6) { C_UDMI(c, t, 0) = -(-C_V(c, t)C_U_G(c, t)[1]) } else if(y>0 && x>6) { C_UDMI(c, t, 0) = -(-C_V(c, t)*-C_U_G(c, t)[1]) } } end_c_loop(c, t) } }

November 30, 2020, 22:10		#2
AlexanderZ Senior Member Alexander Join Date: Apr 2013 Posts: 2,363 Rep Power: 34	how could you know that it doesnt work? __________________ best regards ****************************** press LIKE if this message was helpful

December 1, 2020, 13:40		#7
pakk Senior Member Join Date: Nov 2013 Posts: 1,965 Rep Power: 27	And does this give errors? Code: DEFINE_ADJUST(dudy, domain) { Thisshouldgiveanerror() ; }

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December 1, 2020, 13:38		#6
pakk Senior Member Join Date: Nov 2013 Posts: 1,965 Rep Power: 27	You forgot semicolons where i changed the code, obviously. You also forgot to show the test result. How does UDM 0 look like if you plot with this UDF?