Update helpers.m2

MatrixSchubert/Code/helpers.m2

@@ -1,50 +1 @@
 
--- Utility routines --
-
---------------------------------
---auxiliary function for generating a generic matrix of z variables
---INPUT: integers n,m
---OUTPUT: an n by m generic matrix with entries z_(i,j)
---NOTE: the ring automatically comes equipped with the antidiagonal term order
---TODO: allow user to input the field they want as an option
------------------------------------
-
-genMat = method(
-    Options => {
-	CoefficientRing => QQ,
-	Variable => getSymbol "z"
-	}
-    )
-genMat (ZZ,ZZ) := o -> (n,m) -> (
-    k := o.CoefficientRing;
-    zEntries := flatten table (n,m,(i,j) -> (i,j));
-    z := o.Variable;
-    degs := apply(zEntries,i-> i_1-i_0 + m); --are there better ways to make the antidiagonal weights? prob
-    Q := k(monoid[z_(1,1)..z_(n,m)]);
-    Mmut := mutableMatrix(Q,n,m);
-    for box in zEntries do (
-        Mmut_(box) = Q_(m*(box_0) + box_1);
-    );
-    matrix Mmut
-    )
-
-
---------------------------------
---auxiliary function for getting the index of a variable in a ring
---INPUT: an indexed variable
---OUTPUT: the index of the variable
---TODO: add docs
---SUGGESTION: (from Anton) `indexOfVariable = v -> ( i:= index v; last toList R.generatorSymbols#i )`  -- need `debug Core` to use `R.generatorSymbols`
---SUGGESTION: (from Ayah) `(expression(x_1))#1`
---SUGGESTION: (from Mahrud) `last baseName x_(1,2)`
------------------------------------
-indexOfVariable = method()
-indexOfVariable RingElement := Sequence => (elem) -> (
-    last baseName elem
-)
-indexOfVariable RingElement := List => (elem) -> (
-    last baseName elem
-)
-indexOfVariable RingElement := ZZ => (elem) -> (
-    last baseName elem
-)