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### Problems with heft vectors in M2

I am working with the "NormalToricVarieties" package in M2.

Part of my research involves determining when the higher cohomology groups of certain twists of the structure sheaf of a toric variety vanish. I have a specific example where in computing HH^1(X,OO_X(1,1)) I am confronted with the following error:

stdio:8:3:(3): error: heft vector required that is positive on the degrees of the variables {0, 1, 2, 3, 4, 5, 6}

I know that this group should be trivial but somehow the absence of a heft vector is bothering the compiler. I'm not sure whether or not there is a way to get M2 to compute this group.

Do you happen to know of any workarounds in this situation? I'd greatly appreciate any insight you may have.

The example I am using is as follows:

loadPackage "NormalToricVarieties";
Rho = {
{  0 ,  0 ,  0 ,  0 , 1 }
, {  1 ,  0 ,  0 ,  0 , 1 }
, {  0 ,  1 ,  0 ,  0 , 1 }
, {  0 ,  0 ,  1 ,  0 , 1 }
, {  0 ,  0 ,  0 ,  1 , 1 }
, { -1 , -2 , -1 , -1 , 1 }
, { -2 , -1 , -1 , -1 , 1 }
};
Sigma = {
{ 2 , 3 , 4 , 5 , 6 }
, { 0 , 1 , 2 , 3 , 4 }
, { 0 , 1 , 2 , 3 , 5 }
, { 0 , 1 , 2 , 4 , 5 }
, { 0 , 1 , 3 , 4 , 5 }
, { 0 , 2 , 3 , 4 , 5 }
};
X = normalToricVariety(Rho,Sigma);
HH^2(X,OO_X(1,1)) -- HH^n for n=2 works fine
HH^1(X,OO_X(1,1)) -- HH^n for n=1 gives an error


### Problems with heft vectors in M2

I am working with the "NormalToricVarieties" package in M2.

Part of my research involves determining when the higher cohomology groups of certain twists of the structure sheaf of a toric variety vanish. I have a specific example where in computing HH^1(X,OO_X(1,1)) I am confronted with the following error:

stdio:8:3:(3): error: heft vector required that is positive on the degrees of the variables {0, 1, 2, 3, 4, 5, 6}

I know that this group should be trivial but somehow the absence of a heft vector is bothering the compiler. I'm not sure whether or not there is a way to get M2 to compute this group.

Do you Does anyone happen to know of any workarounds in this situation? I'd greatly appreciate any insight you may have.situation?

The example I am using is as follows:

loadPackage "NormalToricVarieties";
Rho = {
{  0 ,  0 ,  0 ,  0 , 1 }
, {  1 ,  0 ,  0 ,  0 , 1 }
, {  0 ,  1 ,  0 ,  0 , 1 }
, {  0 ,  0 ,  1 ,  0 , 1 }
, {  0 ,  0 ,  0 ,  1 , 1 }
, { -1 , -2 , -1 , -1 , 1 }
, { -2 , -1 , -1 , -1 , 1 }
};
Sigma = {
{ 2 , 3 , 4 , 5 , 6 }
, { 0 , 1 , 2 , 3 , 4 }
, { 0 , 1 , 2 , 3 , 5 }
, { 0 , 1 , 2 , 4 , 5 }
, { 0 , 1 , 3 , 4 , 5 }
, { 0 , 2 , 3 , 4 , 5 }
};
X = normalToricVariety(Rho,Sigma);
HH^2(X,OO_X(1,1)) -- HH^n for n=2 works fine
HH^1(X,OO_X(1,1)) -- HH^n for n=1 gives an error


### Problems with heft vectors in M2

I hope this question is on-topic on this forum.

I am working with the "NormalToricVarieties" package in M2.

Part of my research involves determining when the higher cohomology groups of certain twists of the structure sheaf of a toric variety vanish. I have a specific example where in computing HH^1(X,OO_X(1,1)) I am confronted with the following error:

stdio:8:3:(3): error: heft vector required that is positive on the degrees of the variables {0, 1, 2, 3, 4, 5, 6}

I know that this group should be trivial but somehow the absence of a heft vector is bothering the compiler. I'm not sure whether or not there is a way to get M2 to compute this group.

Does anyone happen to know of any workarounds in this situation?

The example I am using is as follows:

loadPackage "NormalToricVarieties";
Rho = {
{  0 ,  0 ,  0 ,  0 , 1 }
, {  1 ,  0 ,  0 ,  0 , 1 }
, {  0 ,  1 ,  0 ,  0 , 1 }
, {  0 ,  0 ,  1 ,  0 , 1 }
, {  0 ,  0 ,  0 ,  1 , 1 }
, { -1 , -2 , -1 , -1 , 1 }
, { -2 , -1 , -1 , -1 , 1 }
};
Sigma = {
{ 2 , 3 , 4 , 5 , 6 }
, { 0 , 1 , 2 , 3 , 4 }
, { 0 , 1 , 2 , 3 , 5 }
, { 0 , 1 , 2 , 4 , 5 }
, { 0 , 1 , 3 , 4 , 5 }
, { 0 , 2 , 3 , 4 , 5 }
};
X = normalToricVariety(Rho,Sigma);
HH^2(X,OO_X(1,1)) -- HH^n for n=2 works fine
HH^1(X,OO_X(1,1)) -- HH^n for n=1 gives an error

 4 retagged FrédéricC 2339 ●3 ●27 ●47

### Problems with heft vectors in M2

I hope this question is on-topic on this forum.

I am working with the "NormalToricVarieties" package in M2.

Part of my research involves determining when the higher cohomology groups of certain twists of the structure sheaf of a toric variety vanish. I have a specific example where in computing HH^1(X,OO_X(1,1)) I am confronted with the following error:

stdio:8:3:(3): error: heft vector required that is positive on the degrees of the variables {0, 1, 2, 3, 4, 5, 6}

I know that this group should be trivial but somehow the absence of a heft vector is bothering the compiler. I'm not sure whether or not there is a way to get M2 to compute this group.

Does anyone happen to know of any workarounds in this situation?

The example I am using is as follows:

loadPackage "NormalToricVarieties";
Rho = {
{  0 ,  0 ,  0 ,  0 , 1 }
, {  1 ,  0 ,  0 ,  0 , 1 }
, {  0 ,  1 ,  0 ,  0 , 1 }
, {  0 ,  0 ,  1 ,  0 , 1 }
, {  0 ,  0 ,  0 ,  1 , 1 }
, { -1 , -2 , -1 , -1 , 1 }
, { -2 , -1 , -1 , -1 , 1 }
};
Sigma = {
{ 2 , 3 , 4 , 5 , 6 }
, { 0 , 1 , 2 , 3 , 4 }
, { 0 , 1 , 2 , 3 , 5 }
, { 0 , 1 , 2 , 4 , 5 }
, { 0 , 1 , 3 , 4 , 5 }
, { 0 , 2 , 3 , 4 , 5 }
};
X = normalToricVariety(Rho,Sigma);
HH^2(X,OO_X(1,1)) -- HH^n for n=2 works fine
HH^1(X,OO_X(1,1)) -- HH^n for n=1 gives an error