How can I program gams code? (I wnat to select a adequate equation if conditions are satisfactory)

GAMS
1

Dear sir,

I wnat to know how to select a satisfactory equation if conditions are satisfactory on gams coding.

For example, I have a scheduling assignment ablout pilot…
While gams coding, I should declare SETs, Parameter, Table, Scalar, Equations, etc.
I declare Equations and then define Equations. There are three equations.
I have to add another equation. However, that equation should be executed only if conditions are satisfactory.

Here is my Questioning point.
When I declare equations and define equations, Are there any method or syntax to solve my question?

Best regards…

–
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2

Hi Youngki,

What I understand from your e-mail is that you’re trying to write a
constrain that’s only part of the problem when variables have certain
values. Is this correct ?

Regards
Claudio

On Thu, Jan 23, 2014 at 2:40 AM, YOUNGKI CHOI wrote:

Dear sir,

I wnat to know how to select a satisfactory equation if conditions are
satisfactory on gams coding.

For example, I have a scheduling assignment ablout pilot…
While gams coding, I should declare SETs, Parameter, Table, Scalar,
Equations, etc.
I declare Equations and then define Equations. There are three equations.
I have to add another equation. However, that equation should be executed
only if conditions are satisfactory.

Here is my Questioning point.
When I declare equations and define equations, Are there any method or
syntax to solve my question?

Best regards…

–
“gamsworld” group.
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3

2014년 1월 23일 목요일 오후 2시 40분 9초 UTC+9, YOUNGKI CHOI 님의 말:

Dear sir,

I wnat to know how to select a satisfactory equation if conditions are satisfactory on gams coding.

For example, I have a scheduling assignment ablout pilot…
While gams coding, I should declare SETs, Parameter, Table, Scalar, Equations, etc.
I declare Equations and then define Equations. There are three equations.
I have to add another equation. However, that equation should be executed only if conditions are satisfactory.

Here is my Questioning point.
When I declare equations and define equations, Are there any method or syntax to solve my question?

Best regards…

–
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4

I have some details, Claudio…
my coding is below…

set f / bf, ac, sa, ca, tr, ra / ***these elements is actually imported from excel file.
s / 1, 2, 3, 4,/
p / … /
t / …/
f_m(f) / bf, ac / *****these elements is also imported from excel file.
…
equations
eq6(f,s)
eq7(f,s)
…
…
eq6(f,s)…
SUM((p,t), X(f,s,p,t)) =l= 5
eq7(f,s)$f_m(f)… *******Q(1) Here!! is my question…
SUM((p,t), X(f,s,p,t)) =l= 2
…

AboutQ(1)…
f_m(f) is imported from excel file.
If f_m(f) has no elements, I don’t wanna eq7 to be executed.
Eventually, whether elements in f_m(f) exist or not, I want my gams done.

Best regards…

–
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5

Youngki, if f_m(f) isn’t supposed to be zero when its filled, you can
use something like

eq7(f,s)$(f_m(f) ne 0)…

regards
Claudio

On Sat, Feb 8, 2014 at 12:27 AM, YOUNGKI CHOI wrote:

2014년 1월 23일 목요일 오후 2시 40분 9초 UTC+9, YOUNGKI CHOI 님의 말:

Dear sir,

I wnat to know how to select a satisfactory equation if conditions are
satisfactory on gams coding.

For example, I have a scheduling assignment ablout pilot…
While gams coding, I should declare SETs, Parameter, Table, Scalar,
Equations, etc.
I declare Equations and then define Equations. There are three equations.
I have to add another equation. However, that equation should be executed
only if conditions are satisfactory.

Here is my Questioning point.
When I declare equations and define equations, Are there any method or
syntax to solve my question?

Best regards…

–
“gamsworld” group.
To unsubscribe from this group and stop receiving emails from it, send an
email to gamsworld+unsubscribe@googlegroups.com.
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