Function GMP::Row::GetLeftHandSide(GMP, row)

# GMP::Row::GetLeftHandSide

The function GMP::Row::GetLeftHandSide returns the left-hand-side value of a row as present in the generated mathematical program. This function is typically used for ranged constraints.

Note that this function does not return the (evaluated) level value of a row; you should use the function GMP::Solution::GetRowValue instead.
GMP::Row::GetLeftHandSide(
GMP,            ! (input) a generated mathematical program
row             ! (input) a scalar reference or row number
)


## Arguments

GMP

An element in AllGeneratedMathematicalPrograms.

row

A scalar reference to an existing row in the matrix or an element in the set Integers in the range $$\{ 0 .. m-1 \}$$ where $$m$$ is the number of rows in the matrix.

## Return Value

The function returns the left-hand-side value of the specified row.

Note

If the row has a unit then the scaled left-hand-side value is returned (without unit).

## Example

Assume that ‘c1’ is a constraint in mathematical program ‘MP’ with a unit as defined by:

Quantity SI_Mass {
BaseUnit      :  kg;
Conversions   :  ton -> kg : # -> # * 1000;
}
Parameter wght_lower {
Unit          :  ton;
InitialValue  :  20;
}
Parameter wght_upper {
Unit          :  ton;
InitialValue  :  60;
}
Constraint c1 {
Unit          :  ton;
Definition    :  wght_lower <= -x1 + 2 * x2 <= wght_upper;
}


If we want to multiply the left-hand-side value by 1.5 and assign it as the new value by using function GMP::Row::SetLeftHandSide we can use

lhs1 := 1.5 * (GMP::Row::GetLeftHandSide( 'MP', c1 )) [ton];

GMP::Row::SetLeftHandSide( 'MP', c1, lhs1 );


if ‘lhs1’ is a parameter with unit [ton], or we can use

lhs2 := 1.5 * GMP::Row::GetLeftHandSide( 'MP', c1 );

GMP::Row::SetLeftHandSide( 'MP', c1, lhs2 * GMP::Row::GetScale( 'MP', c1 ) );


if ‘lhs2’ is a parameter without a unit.