diff --git a/spinoza/src/measurement.rs b/spinoza/src/measurement.rs
index 7b24b52..68b8528 100644
--- a/spinoza/src/measurement.rs
+++ b/spinoza/src/measurement.rs
@@ -105,4 +105,108 @@ mod tests {
 
         assert_float_closeness(sum, 1.0, 0.001);
     }
+
+    #[test]
+    fn test_measure_qubit_known_state() {
+        let n = 3;
+        let mut reals = Vec::with_capacity(1 << n);
+        let mut imags = Vec::with_capacity(1 << n);
+
+        let vals = vec![
+            0.034172256444052966,
+            0.29007027387615136,
+            -0.1300556493088507,
+            0.47222164829858637,
+            -0.032338373524095645,
+            0.26511510737291843,
+            0.1259630181898572,
+            -0.09645897805840803,
+            -0.31931099330088214,
+            -0.24644972468157703,
+            -0.15963222942036193,
+            -0.14329373536970438,
+            -0.1564141838467382,
+            -0.4751067410290973,
+            0.1034273381193853,
+            -0.32966556091031934,
+        ];
+
+        let mut i = 0;
+        while i < vals.len() - 1 {
+            reals.push(vals[i]);
+            imags.push(vals[i + 1]);
+            i += 2;
+        }
+
+        let mut state = State { reals, imags, n };
+
+        let epsilon = 0.001;
+
+        measure_qubit(&mut state, 0, true, Some(0));
+
+        assert_float_closeness(state.reals[0], 0.04528096797370981, epsilon);
+        assert_float_closeness(state.imags[0], 0.38436627101331156, epsilon);
+        assert_float_closeness(state.reals[1], 0.0, epsilon);
+        assert_float_closeness(state.imags[1], 0.0, epsilon);
+
+        assert_float_closeness(state.reals[2], -0.042850926694402595, epsilon);
+        assert_float_closeness(state.imags[2], 0.3512986830692283, epsilon);
+        assert_float_closeness(state.reals[3], 0.0, epsilon);
+        assert_float_closeness(state.imags[3], 0.0, epsilon);
+
+        assert_float_closeness(state.reals[4], -0.42311255872092046, epsilon);
+        assert_float_closeness(state.imags[4], -0.32656556082875193, epsilon);
+        assert_float_closeness(state.reals[5], 0.0, epsilon);
+        assert_float_closeness(state.imags[5], 0.0, epsilon);
+
+        assert_float_closeness(state.reals[6], -0.2072612811212442, epsilon);
+        assert_float_closeness(state.imags[6], -0.6295543626114914, epsilon);
+        assert_float_closeness(state.reals[7], 0.0, epsilon);
+        assert_float_closeness(state.imags[7], 0.0, epsilon);
+        println!("{state}");
+
+        measure_qubit(&mut state, 1, true, Some(0));
+        assert_float_closeness(state.reals[0], 0.06861878352538178, epsilon);
+        assert_float_closeness(state.imags[0], 0.5824686866330654, epsilon);
+        assert_float_closeness(state.reals[1], 0.0, epsilon);
+        assert_float_closeness(state.imags[1], 0.0, epsilon);
+
+        assert_float_closeness(state.reals[2], 0.0, epsilon);
+        assert_float_closeness(state.imags[2], 0.0, epsilon);
+        assert_float_closeness(state.reals[3], 0.0, epsilon);
+        assert_float_closeness(state.imags[3], 0.0, epsilon);
+
+        assert_float_closeness(state.reals[4], -0.6411848150109799, epsilon);
+        assert_float_closeness(state.imags[4], -0.49487748447346463, epsilon);
+        assert_float_closeness(state.reals[5], 0.0, epsilon);
+        assert_float_closeness(state.imags[5], 0.0, epsilon);
+
+        assert_float_closeness(state.reals[6], 0.0, epsilon);
+        assert_float_closeness(state.imags[6], 0.0, epsilon);
+        assert_float_closeness(state.reals[7], 0.0, epsilon);
+        assert_float_closeness(state.imags[7], 0.0, epsilon);
+        println!("{state}");
+
+        measure_qubit(&mut state, 2, true, Some(1));
+        assert_float_closeness(state.reals[0], -0.7916334352111761, epsilon);
+        assert_float_closeness(state.imags[0], -0.6109963209838112, epsilon);
+        assert_float_closeness(state.reals[1], 0.0, epsilon);
+        assert_float_closeness(state.imags[1], 0.0, epsilon);
+
+        assert_float_closeness(state.reals[2], 0.0, epsilon);
+        assert_float_closeness(state.imags[2], 0.0, epsilon);
+        assert_float_closeness(state.reals[3], 0.0, epsilon);
+        assert_float_closeness(state.imags[3], 0.0, epsilon);
+
+        assert_float_closeness(state.reals[4], 0.0, epsilon);
+        assert_float_closeness(state.imags[4], 0.0, epsilon);
+        assert_float_closeness(state.reals[5], 0.0, epsilon);
+        assert_float_closeness(state.imags[5], 0.0, epsilon);
+
+        assert_float_closeness(state.reals[6], 0.0, epsilon);
+        assert_float_closeness(state.imags[6], 0.0, epsilon);
+        assert_float_closeness(state.reals[7], 0.0, epsilon);
+        assert_float_closeness(state.imags[7], 0.0, epsilon);
+        println!("{state}");
+    }
 }