From 3cda66441e12c04a7305fe96bb5ca89b77ff93d5 Mon Sep 17 00:00:00 2001
From: Deepak <dmallubhotla+github@gmail.com>
Date: Tue, 24 Nov 2020 13:57:37 -0600
Subject: [PATCH] adds full functionality test for find_n_gap

---
 pysuperconductor/os_gap_calc.py | 22 ++++++++++++++++++++++
 tests/test_os_gap_calc.py       |  9 +++++++++
 2 files changed, 31 insertions(+)

diff --git a/pysuperconductor/os_gap_calc.py b/pysuperconductor/os_gap_calc.py
index 7f46417..668a0c8 100644
--- a/pysuperconductor/os_gap_calc.py
+++ b/pysuperconductor/os_gap_calc.py
@@ -1,6 +1,9 @@
 import numpy  # type: ignore
 import scipy.integrate as integrate  # type: ignore
 import scipy.optimize  # type: ignore
+import logging
+
+from typing import Tuple
 
 
 def energy(freq: float, delta: float) -> float:
@@ -68,3 +71,22 @@ def n_integral(temp: float, delta: float, mu_star: float) -> float:
 	lower = integrate.quad(integrand, 0, intermediate)[0]
 	upper = integrate.quad(integrand, intermediate, numpy.inf)[0]
 	return lower + upper
+
+
+def find_gap_for_n(
+	temp: float,
+	n_bare: float,
+	debye_frequency: float,
+	nv: float
+) -> Tuple[float, float]:
+	n = n_bare * find_gap(0, 0, debye_frequency, nv)
+	nv_inv = 1 / nv
+	sol = scipy.optimize.root(
+		lambda x: [
+			gap_integral(temp, x[0], x[1], debye_frequency) - nv_inv,
+			n_integral(temp, x[0], x[1]) - n
+		],
+		x0=[debye_frequency / (numpy.sinh(nv_inv)), 0]
+	)
+	logging.debug(sol)
+	return sol.x
diff --git a/tests/test_os_gap_calc.py b/tests/test_os_gap_calc.py
index 2e6935f..57e168e 100644
--- a/tests/test_os_gap_calc.py
+++ b/tests/test_os_gap_calc.py
@@ -67,3 +67,12 @@ def test_n_integral():
 		verbose=True
 	)
 	assert not record
+
+
+def test_find_n_gap():
+	actual = pysuperconductor.os_gap_calc.find_gap_for_n(.3, .1, 100, .2)
+	numpy.testing.assert_almost_equal(
+		actual[0], 1.0296692197710933,
+		decimal=7, err_msg="did not find correct delta",
+		verbose=True
+	)