- Procedure GMP::Column::SetLowerBound(GMP, column, value)
GMP::Column::SetLowerBound
The procedure GMP::Column::SetLowerBound
changes the lower bound of
a column in a generated mathematical program.
GMP::Column::SetLowerBound(
GMP, ! (input) a generated mathematical program
column, ! (input) a scalar reference or column number
value ! (input) a numerical expression
)
Arguments
- GMP
An element in
AllGeneratedMathematicalPrograms
.- column
A scalar reference to an existing column in the matrix or an element in the set
Integers
in the range \(\{ 0 .. n-1 \}\) where \(n\) is the number of columns in the matrix.- value
The new value assigned to the lower bound of the column.
Return Value
The procedure returns 1 on success, and 0 otherwise.
Note
Use
GMP::Column::SetLowerBoundMulti
orGMP::Column::SetLowerBoundRaw
if the lower bounds of many columns have to be set, because that will be more efficient.If the column has a unit then value should have the same unit. If value has no unit then you should multiply it by the column scale, as returned by the function
GMP::Column::GetScale
.
Example
Assume that x1
is a variable in mathematical program MP
with a unit
as defined by:
Quantity SI_Mass {
BaseUnit : kg;
Conversions : ton -> kg : # -> # * 1000;
}
Parameter min_wght {
Unit : ton;
InitialValue : 20;
}
Variable x1 {
Range : [min_wght, inf);
Unit : ton;
}
Then if we run the following code
GMP::Column::SetLowerBound( 'MP', x1, 20 [ton] );
lb1 := GMP::Column::GetLowerBound( 'MP', x1 );
display lb1;
GMP::Column::SetLowerBound( 'MP', x1, 30 );
lb2 := GMP::Column::GetLowerBound( 'MP', x1 );
display lb2;
GMP::Column::SetLowerBound( 'MP', x1, 40 * GMP::Column::GetScale( 'MP', x1 ) );
lb3 := GMP::Column::GetLowerBound( 'MP', x1 );
display lb3;
(where lb1
, lb2
and lb3
are parameters without a unit) we get the following results:
lb1 := 20 ;
lb2 := 0.030 ;
lb3 := 40 ;