Hi Everyone,
I followed SAS OR example and made some modification as following. However, there are some error message I have no idea how to sole. Could you give me some suggestions? Thank you!
The error message of the following code are:
read data transport_cost_data into [o_city]
_
771
NOTE 771-782: The name 'o_city' hides an outer declaration.
55 {d_city in D_CITY} <transport_cost[o_city,d_city] = col(d_city)>;
______
771
NOTE 771-782: The name 'd_city' hides an outer declaration.
data demand_data;
input d_city $ Demand;
datalines;
Boston 150
New_York 150
;
data supply_data;
input o_city $ Supply;
datalines;
Detroit 200
Pittsburgh 100
;
data transport_cost_data;
input o_city $ Boston New_York;
datalines;
Detroit 30 20
Pittsburgh 40 10
;
proc optmodel;
/* specify parameters */
set <str> O_CITY;
num Supply {O_CITY};
read data supply_data into O_CITY = [o_city] Supply;
print Supply;
set <str> D_CITY;
num Demand {D_CITY};
read data demand_data into D_CITY = [d_city] Demand;
print Demand;
num transport_cost {O_CITY, D_CITY};
read data transport_cost_data into [o_city]
{d_city in D_CITY} <transport_cost[o_city,d_city] = col(d_city)>;
/* model description */
var x{O_CITY,D_CITY} >= 0;
min total_cost = sum{i in O_CITY, j in D_CITY}transport_cost[i,j]*x[i,j];
constraint supply_rule {i in O_CITY}: sum{j in D_CITY}x[i,j]=Supply[i];
constraint demand_rule {j in D_CITY}: sum{i in O_CITY}x[i,j]=Demand[j];
/* solve and output */
solve;
print x;