Fixes complex power for zero

Author: domna

Cargo.lock

@@ -1,6 +1,6 @@
 [package]
 name = "formula-dispersion"
-version = "0.1.1"
+version = "0.1.2"
 authors = ["Florian Dobener <[email protected]>"]
 edition = "2018"
 

Cargo.toml

@@ -73,13 +73,26 @@ pub enum EvaluateResult {
     Number(Complex64),
 }
 
+trait ComplexPower {
+    fn pc(self, exp: Complex64) -> Complex64;
+}
+
+impl ComplexPower for Complex64 {
+    fn pc(self, exp: Complex64) -> Complex64 {
+        if self.re == 0. && self.im == 0. {
+            return Complex64::from(0.);
+        }
+        self.powc(exp)
+    }
+}
+
 impl EvaluateResult {
     fn power(self, other: EvaluateResult) -> EvaluateResult {
         use EvaluateResult::*;
         match (self, other) {
-            (Number(b), Number(exp)) => EvaluateResult::Number(b.powc(exp)),
-            (Number(b), Array(exp)) => EvaluateResult::Array(exp.map(|x| b.powc(*x))),
-            (Array(b), Number(exp)) => EvaluateResult::Array(b.map(|x| x.powc(exp))),
+            (Number(b), Number(exp)) => EvaluateResult::Number(b.pc(exp)),
+            (Number(b), Array(exp)) => EvaluateResult::Array(exp.map(|x| b.pc(*x))),
+            (Array(b), Number(exp)) => EvaluateResult::Array(b.map(|x| x.pc(exp))),
             (Array(b), Array(exp)) => EvaluateResult::Array(
                 Zip::from(&b)
                     .and(&exp)

src/ast.rs

@@ -29,7 +29,7 @@ def test_powc():
     """Using power is working properly"""
 
     parsed = parse("n = lbda ** 3", "lbda", np.array([1.0, 2.0, 3.0]), {}, {})
-    assert_array_almost_equal(parsed, np.array([1.0**2, 8.0**2, 27.0**2]))
+    assert_array_almost_equal(parsed, np.array([1.0, 8.0, 27.0]))
 
 
 def test_sum():
@@ -80,3 +80,20 @@ def test_fails_on_wrong_token():
 
     with pytest.raises(TypeError):
         parse("eps = 3 * 3 * lba", "lbda", np.array([1.0, 2.0, 3.0]), {}, {})
+
+
+def test_sellmeier():
+    formula = "n = sqrt(eps_inf + sum[A * lambda ** e1 / (lambda ** 2 - B**e2)])"
+    # formula = "n =  B ** e2"
+    rep_params = {
+        "A": np.array([1.0, 0.00448263]),
+        "B": np.array([0.0, 1.108205]),
+        "e1": np.array([0.0, 0.0]),
+        "e2": np.array([1.0, 2.0]),
+    }
+    single_params = {"eps_inf": 11.67316}
+    lbda = np.linspace(6250, 23255.814, 100)
+
+    assert_array_almost_equal(
+        lbda, parse(formula, "lambda", lbda, single_params, rep_params)
+    )