How to define a three-dimensional parameter?

Hello,
I need to define a three-dimensional parameter (D(n,h,t)) in my model. The use of tables is used in two-dimensional parameters. Below I am sharing my model and the parameter I want to define. I’ll be happy if you can help me.
Thank you.

Sets;
n> 17 (Marmara, Ege, Akdeniz, iç Anadolu, Doğu Anadolu, Güneydoğu Anadolu, Karadeniz)
h> 1
3 (H1, H2, H3)
t>1*12 (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 )
OCT25MODEL.gms (2.14 KB)
image.png

Sets

*Dağıtım Yapılacak Bölgeler
n 
/1*7/

*Aşı Öncelik Grubu
h 
/1*3/

*Zaman Periyodu
t 
/1*12/

*Araç Tipi
k 
/1*4/

*Araç Kapasitesi
CapC(k) 
/1 1425
 2 2735
 3 4575
 4 7500/
;

*Ana Depo Kapasitesi
Parameters CapWH; 
CapWH=35000;

*Bölge Deposu Kapasitesi
Parameters CapSH; 
CapSH=1140;
 

Variables
TBH(n,h)
Con3(n,h,t)
DD(n,h,t)
Con1(n,h,t)
Con2(n,h,t)
InvWH(t)
InvSH(n,t)
C(n,k,t)
;

Positive Variables
z
TBH(n,h)
Con3(n,h,t)
DD(n,h,t)
Con1(n,h,t)
Con2(n,h,t)
InvWH(t)
InvSH(n,t)
C(n,k,t)
;

Equations
amac
k1(n)
*k2(n)
*k3(n)
*k4(n)
*k5(n)
k6(n)
k7(n)
k8(n)
k9(n)
k10(t)
k11(n)
k12(k)
k13(n,t)
k14(t)
k15(n,t)
k16(n,t)
k17(n,t)
;

amac..                z=e=sum((n,h), TBH(n,h));
k1(n)..               sum ((h),TBH(n,h))=e=sum ((h,t), Con3(n,h,t));
*k2(n)..               sum((h,t)$(ord(t)=1), DD(n,h,t))=l=sum ((h,t)$(ord(t)=1), D(n,h,t)-Con1(n,h,t));
*k3(n)..               sum((h,t)$(ord(t)=2), DD(n,h,t))=l=sum ((h,t)$(ord(t)=2), DD(n,h,t)+Con(n,h,t-1)-Con1(n,h,t)-Con2(n,h,t));
*k4(n)..               sum((h,t)$(ord(t)>2), DD(n,h,t))=l=sum ((h,t)$(ord(t)>2), DD(n,h,t)+Con(n,h,t-1)+Con2(n,h,t-1)-Con1(n,h,t)-Con2(n,h,t))-Con3(n,h,t));
*k5(n)..               sum ((h,t), Con1(n,h,t))=l=sum ((h,t), D(n,h,t));
k6(n)..               sum ((h,t)$(ord(t)=1), Con2(n,h,t))=l=0;
k7(n)..               sum ((h,t)$(ord(t)>1), Con2(n,h,t))=l=sum ((h,t), Con1(n,h,t-1));
k8(n)..               sum ((h,t)$(ord(t)=2), Con3(n,h,t))=l=0;
k9(n)..               sum ((h,t)$(ord(t)>2), Con3(n,h,t))=l=sum ((h,t), Con2(n,h,t-1));
k10(t)..              InvWH(t)=l=CapWH;
k11(n)..              sum ((t), InvSH(n,t))=l=CapSH;
*k12(k)..              sum ((n,t), C(n,k,t))=l=CapC(k);
k13(n,t)..            InvSH(n,t-1)+sum ((k),C(n,k,t))=l=CapSH;
k14(t)$(ord(t)>1)..   InvWH(t)=l=InvWH(t-1)+CapWH-sum ((n,k),C(n,k,t));
k15(n,t)$(ord(t)>1).. InvSH(n,t)=l=InvSH(n,t-1)+sum ((k), C(n,k,t))-sum ((h), Con1(n,h,t));
k16(n,t)$(ord(t)=2).. InvSH(n,t)=l=InvSH(n,t-1)+sum ((k), C(n,k,t))-sum ((h), (Con1(n,h,t)+Con2(n,h,t)));
k17(n,t)$(ord(t)>2).. InvSH(n,t)=l=InvSH(n,t-1)+sum ((k), C(n,k,t))-sum ((h), (Con1(n,h,t)+Con2(n,h,t)+Con3(n,h,t)));

Model OCT25MODEL /all/;
Solve OCT25MODEL using mip max z;

Thank you.

Not clear why you remap from good names (Marmara, Ege, Akdeniz, iç Anadolu, Doğu Anadolu, Güneydoğu Anadolu, Karadeniz) to integers (1*7) but this is independent of your question. Tables can also be used for higher dimensional formats (see https://www.gams.com/latest/docs/UG_DataEntry.html#UG_DataEntry_TablesTablesWithMoreThanTwoDimensions):

Table D(n,h,t)
       1       2       3       4       5       6       7       8       9      10      11      12
1.1 14323   14323   14323   14323   14323   14323   14323   14323   14323   14323   14323   14323
1.2 178148  178148  178148  178148  178148  178148  178148  178148  178148  178148  178148  178148
...

Seems that you solved this all by yourself (see https://newforum.gams.com/t/error-246-code/4092/1).

-Michael