working TCC (Test response funciton)

app/lib/irt/item_response_function.py

@@ -1,4 +1,4 @@
-from models.three_parameter_logitistc import ThreeParameterLogistic
+from lib.irt.models.three_parameter_logistic import ThreeParameterLogistic
 
 class ItemResponseFunction():
   def __init__(self, irt_model):
@@ -6,7 +6,7 @@ class ItemResponseFunction():
 
   def calculate(self, **kwargs):
     if self.model_data.model == '3PL':
-      return ThreeParameterLogistic.new(self.model_data, kwargs).result
+      return ThreeParameterLogistic(self.model_data, kwargs).result()
     else:
       # potentially error out
       return None

app/lib/irt/models/three_parameter_logistic.py

@@ -7,7 +7,6 @@ class ThreeParameterLogistic:
     self.theta = kwargs['theta']
 
   def result(self):
-    a = self.model_params.a
-    c = self.model_params.c
-
-    return c + (1 - c) * (1 / (1 + e**(-a * (self.theta - self.b_param))))
+    a = self.model_params.a_param
+    c = self.model_params.c_param
+    return c + (1 - c) * (1 / (1 + self.e**(-a * (self.theta - self.b_param))))

app/lib/irt/test_response_function.py

@@ -1,12 +1,17 @@
+from lib.irt.item_response_function import ItemResponseFunction
+
 # otherwise known as the Test Characteristic Curve (TCC)
 class TestResponseFunction():
-  def __init__(self, irf):
-    self.irf = irf
+  def __init__(self, irt_model):
+    self.irt_model = irt_model
+    self.irf = ItemResponseFunction(irt_model)
 
   def calculate(self, items, **kwargs):
-    result = 0
+    sum = 0
 
     for item in items:
-      result += irf.calculate(b_param=item.b_param, theta=kwargs['theta'])
+      result = self.irf.calculate(b_param=item.b_param, theta=kwargs['theta'])
+      item.irf = result
+      sum += item.irf
 
-    return result
+    return sum