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Computing polyhedron from MIP

I want to run the following code (I'm using SAGE v6.10 release version 2015-12-18):

P = MixedIntegerLinearProgram()
x = P.new_variable()
A = random_matrix(RR, 3, 2); 
P.add_constraint(A*x <= [2.1,1.5,0.4]) 
P.polyhedron()

However, it outputs the error message:

AttributeError: type object 'float' has no attribute 'fraction_field'

I notices that if instead of using real variables I use only integer variables, then it works fine. For instance:

P = MixedIntegerLinearProgram()
x = P.new_variable()
A = random_matrix(ZZ, 3, 2); 
P.add_constraint(A*x <= [2,1,0]) 
P.polyhedron()

outputs:

A 2-dimensional polyhedron in QQ^2 defined as the convex hull of 1 vertex and 2 rays

What do you suggest to overcome this problem?

Thanks

Computing polyhedron from MIP

I want to run the following code (I'm using SAGE v6.10 release version 2015-12-18):

P = MixedIntegerLinearProgram()
x = P.new_variable()
A = random_matrix(RR, 3, 2); 
P.add_constraint(A*x <= [2.1,1.5,0.4]) 
P.polyhedron()

However, it outputs the error message:

AttributeError: type object 'float' has no attribute 'fraction_field'

I notices noticed that if instead of using real variables I use only integer variables, then it works fine. For instance:

P = MixedIntegerLinearProgram()
x = P.new_variable()
A = random_matrix(ZZ, 3, 2); 
P.add_constraint(A*x <= [2,1,0]) 
P.polyhedron()

outputs:

A 2-dimensional polyhedron in QQ^2 defined as the convex hull of 1 vertex and 2 rays

What do you suggest to overcome this problem?

Thanks

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Computing polyhedron from MIP

I want to run the following code (I'm using SAGE v6.10 release version 2015-12-18):

P = MixedIntegerLinearProgram()
x = P.new_variable()
A = random_matrix(RR, 3, 2); 
P.add_constraint(A*x <= [2.1,1.5,0.4]) 
P.polyhedron()

However, it outputs the error message:

AttributeError: type object 'float' has no attribute 'fraction_field'

I noticed that if instead of using real variables I use only integer variables, then it works fine. For instance:

P = MixedIntegerLinearProgram()
x = P.new_variable()
A = random_matrix(ZZ, 3, 2); 
P.add_constraint(A*x <= [2,1,0]) 
P.polyhedron()

outputs:

A 2-dimensional polyhedron in QQ^2 defined as the convex hull of 1 vertex and 2 rays

What do you suggest to overcome this problem?

Thanks

Computing polyhedron from MIP

I want to run the following code (I'm using SAGE v6.10 release version 2015-12-18):

P = MixedIntegerLinearProgram()
x = P.new_variable()
A = random_matrix(RR, 3, 2); 
P.add_constraint(A*x <= [2.1,1.5,0.4]) 
P.polyhedron()

However, it outputs the error message:

AttributeError: type object 'float' has no attribute 'fraction_field'

I noticed that if instead of using real variables I use only integer variables, then it works fine. For instance:

P = MixedIntegerLinearProgram()
x = P.new_variable()
A = random_matrix(ZZ, 3, 2); 
P.add_constraint(A*x <= [2,1,0]) 
P.polyhedron()

outputs:

A 2-dimensional polyhedron in QQ^2 defined as the convex hull of 1 vertex and 2 rays

What do you suggest to overcome this problem?

Thanks

Computing polyhedron from MIP

I want to run the following code (I'm using SAGE v6.10 release version 2015-12-18):

P = MixedIntegerLinearProgram()
x = P.new_variable()
A = random_matrix(RR, 3, 2); 
P.add_constraint(A*x <= [2.1,1.5,0.4]) 
P.polyhedron()

However, it outputs the error message:

AttributeError: type object 'float' has no attribute 'fraction_field'

I noticed that if instead of using real variables I use only integer variables, then it works fine. For instance:

P = MixedIntegerLinearProgram()
x = P.new_variable()
A = random_matrix(ZZ, 3, 2); 
P.add_constraint(A*x <= [2,1,0]) 
P.polyhedron()

outputs:

A 2-dimensional polyhedron in QQ^2 defined as the convex hull of 1 vertex and 2 rays

What do you suggest to overcome this problem?

Thanks