Add strucures and check compiles

crates/accelerate/src/xx_decompose/mod.rs

@@ -10,6 +10,9 @@
 // copyright notice, and modified files need to carry a notice indicating
 // that they have been altered from the originals.
 
+/// Conventions in journal article and Python code
+/// A "program" means a unitary opeator.
+
 pub mod circuits;
 pub mod decomposer;
 pub mod utilities;

crates/accelerate/src/xx_decompose/polytopes.rs

@@ -1,3 +1,6 @@
+use crate::xx_decompose::types::Coordinate;
+use crate::xx_decompose::utilities::EPSILON;
+
 /// The raw data underlying a ConvexPolytope.  Describes a single /// polytope, specified by families of `inequalities` and `equalities`, each
 /// entry of which respectively corresponds to
 ///
@@ -6,12 +9,28 @@
 /// and
 ///
 ///     equalities[j][0] + sum_i equalities[j][i] * xi == 0.
-struct ConvexPolytopeData {
+struct ConvexPolytopeData<const MI:usize, const NI: usize, const ME:usize, const NE: usize> {
+    inequalities: [[f64; MI]; NI],
+    equalities: [[f64; ME]; NE],
+    name: String,
 }
 
 /// The raw data of a union of convex polytopes.
-struct PolytopeData {
-    data: Vec<ConvexPolytopeData>,
+struct PolytopeData<const MI:usize, const NI: usize, const ME:usize, const NE: usize> {
+    convex_subpolytopes: Vec<ConvexPolytopeData<MI, NI, ME, NE>>,
+}
+
+// TODO: In the original, this is not a class-instance method. Could be I think.
+/// Tests whether `polytope` contains `point.
+fn polytope_has_element<const MI:usize, const NI: usize, const ME:usize, const NE: usize>
+    (polytope: ConvexPolytopeData<MI, NI, ME, NE>, point: &[f64; MI - 1]) -> bool {
+    polytope.inequalities
+            .iter()
+            .all(|ie| (-EPSILON <= ie[0] + point.iter().zip(&ie[1..]).map(|(p, i)| p * i).sum::<f64>()))
+    //         &&
+    // polytope.equalities
+    //         .iter()
+    //         .all(|e| (e[0] + point.iter().zip(&e[1..]).map(|(p, i)| p * i).sum::<f64>() <= EPSILON))
 }
 
 /// Describes those two-qubit programs accessible to a given sequence of XX-type interactions.
@@ -27,7 +46,7 @@ struct XXPolytope {
 impl XXPolytope {
 
     // Method add_strength appears in the original Python
-    // But it is only called in the test suite.   
+    // But it is only called in the test suite.
     //    fn add_strength() {}
 }
 

crates/accelerate/src/xx_decompose/types.rs

@@ -55,20 +55,20 @@ pub(crate) struct Coordinate {
 
 impl Coordinate {
 
-    pub(crate) fn reflect(&self, scalars: &[i32; 3]) -> Coordinate {
+    pub(crate) fn reflect(&self, scalars: &[f64; 3]) -> Coordinate {
         Coordinate {
-            data: [self.data[0] * (scalars[0]) as f64,
-                   self.data[1] * (scalars[1]) as f64,
-                   self.data[2] * (scalars[2]) as f64,]
+            data: [self.data[0] * (scalars[0]),
+                   self.data[1] * (scalars[1]),
+                   self.data[2] * (scalars[2]),]
         }
     }
 
-    pub(crate) fn shift(&self, scalars: &[i32; 3]) -> Coordinate {
+    pub(crate) fn shift(&self, scalars: &[f64; 3]) -> Coordinate {
         let pi2 = PI / 2.0;
         Coordinate {
-            data: [pi2 * self.data[0] + (scalars[0]) as f64,
-                   pi2 * self.data[1] + (scalars[1]) as f64,
-                   pi2 * self.data[2] + (scalars[2]) as f64,]
+            data: [pi2 * self.data[0] + (scalars[0]),
+                   pi2 * self.data[1] + (scalars[1]),
+                   pi2 * self.data[2] + (scalars[2]),]
         }
     }
 
@@ -77,6 +77,10 @@ impl Coordinate {
         let d = self.data[i as usize] - other.data[j as usize];
         (d.abs() % PI).abs()
     }
+
+    pub(crate) fn iter(&self) -> std::slice::Iter<'_, f64> {
+        self.data.iter()
+    }    
 }
 
 // Forward indexing into `Coordinate` to the field `data`.

crates/accelerate/src/xx_decompose/utilities.rs

@@ -3,8 +3,9 @@ pub(crate) const EPSILON: f64 = 1e-6;
 use std::f64::consts::PI;
 
 // The logic in `safe_acos` is copied from the Python original.
-// The following comment is copied as well.
+// The following one-line comment is copied from the Python as well.
 // TODO: THIS IS A STOPGAP!!!
+//
 /// Has the same behavior as `f64::acos` except that an
 /// argument a bit greater than `1` or less than `-1` is
 /// valid and returns the value at `1` or `-1`.

crates/accelerate/src/xx_decompose/weyl.rs

@@ -25,11 +25,11 @@ pub(crate) static REFLECTION_NAMES: [ReflectionName; 4] = [ReflectionName::NoRef
 // where reflection scalars (a, b, c) model the map (x, y, z) |-> (ax, by, cz),
 // global phase is a complex unit, and gate constructors are applied in sequence
 // and by conjugation to the first qubit and are passed pi as a parameter.
-static reflection_options: [(&[i32; 3], Complex64, &[StandardGate]); 4]  =
-    [(&[1, 1, 1], C_ONE, &[]), // 0
-     (&[-1, -1, 1], C_ONE, &[StandardGate::RZGate]), // 1
-     (&[-1, 1, -1], C_ONE, &[StandardGate::RYGate]), // 2
-     (&[1, -1, -1], C_ONE, &[StandardGate::RXGate]), // 3
+static reflection_options: [(&[f64; 3], Complex64, &[StandardGate]); 4]  =
+    [(&[1., 1., 1.], C_ONE, &[]), // 0
+     (&[-1., -1., 1.], C_ONE, &[StandardGate::RZGate]), // 1
+     (&[-1., 1., -1.], C_ONE, &[StandardGate::RYGate]), // 2
+     (&[1., -1., -1.], C_ONE, &[StandardGate::RXGate]), // 3
     ];
 
 
@@ -56,15 +56,15 @@ pub(crate) static SHIFT_NAMES: [ShiftName; 8] = [
     ShiftName::XYZShift,
     ];
 
-static shift_options: [(&[i32; 3], Complex64, &[StandardGate]); 8] =
-[(&[0, 0, 0], C_ONE, &[]),
- (&[0, 0, 1], IM, &[StandardGate::RZGate]),
- (&[0, 1, 0], M_IM, &[StandardGate::RYGate]),
- (&[0, 1, 1], C_ONE, &[StandardGate::RYGate, StandardGate::RZGate]),
- (&[1, 0, 0], M_IM, &[StandardGate::RXGate]),
- (&[1, 0, 1], C_ONE, &[StandardGate::RXGate, StandardGate::RZGate]),
- (&[1, 1, 0], C_M_ONE, &[StandardGate::RXGate, StandardGate::RYGate]),
- (&[1, 1, 1], M_IM, &[StandardGate::RXGate, StandardGate::RYGate, StandardGate::RZGate]),
+static shift_options: [(&[f64; 3], Complex64, &[StandardGate]); 8] =
+[(&[0., 0., 0.], C_ONE, &[]),
+ (&[0., 0., 1.], IM, &[StandardGate::RZGate]),
+ (&[0., 1., 0.], M_IM, &[StandardGate::RYGate]),
+ (&[0., 1., 1.], C_ONE, &[StandardGate::RYGate, StandardGate::RZGate]),
+ (&[1., 0., 0.], M_IM, &[StandardGate::RXGate]),
+ (&[1., 0., 1.], C_ONE, &[StandardGate::RXGate, StandardGate::RZGate]),
+ (&[1., 1., 0.], C_M_ONE, &[StandardGate::RXGate, StandardGate::RYGate]),
+ (&[1., 1., 1.], M_IM, &[StandardGate::RXGate, StandardGate::RYGate, StandardGate::RZGate]),
  ];