[Mlir-commits] [mlir] [MLIR][Presburger] Add Gram-Schmidt (PR #70843)

[Arjun P]

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@@ -548,4 +548,27 @@ Fraction FracMatrix::determinant(FracMatrix *inverse) const {
     determinant *= m.at(i, i);
 
   return determinant;
+}
+
+FracMatrix FracMatrix::gramSchmidt() const {
+
+    // Create a copy of the argument to store
+    // the orthogonalised version.
+    FracMatrix orth(*this);
+    Fraction projectionScale;
+
+    // For each vector (row) in the matrix,
+    // subtract its unit projection along
+    // each of the previous vectors.
+    // This ensures that it has no component
+    // in the direction of any of the
+    // previous vectors.
+    for (unsigned i = 1; i < getNumRows(); i++) {
+        for (unsigned j = 0; j < i; j++) {
+            projectionScale = dotProduct(orth.getRow(i), orth.getRow(j)) /
+                              dotProduct(orth.getRow(j), orth.getRow(j));
----------------
Superty wrote:

what happens if some row becomes zero?

https://github.com/llvm/llvm-project/pull/70843