--- a/tvii/logistic_regression.py	Mon Sep 04 12:01:57 2017 -0700
+++ b/tvii/logistic_regression.py	Mon Sep 04 12:04:58 2017 -0700
@@ -81,30 +81,3 @@
     A = sigmoid(np.dot(w.T, X) + b)
     cost = np.sum(Y*np.log(A) + (1 - Y)*np.log(1 - A))
     return (-1./m)*cost
-
-
-def logistic_regression(_):
-    """the slow way"""
-    J = 0
-    dw1 =0
-    dw2=0
-    db=0
-    raise NotImplementedError('TODO')
-
-
-def logistic_regression(nx):
-    dw = np.zeros(nx)
-    # TODO
-    # z = np.dot(wT, x) + b  # "boradcasting
-    raise NotImplementedError('TODO')
-
-# derivatives:
-# dz1 = a1 - y1 ; dz2 = a2 - y2 ; ....
-# dZ = [ dz1 dz2 ... dzm ]
-# Z = w'X + b = np.dot(w', X) + b
-# A sigmoid(Z)
-#dZ = A - Y
-#dw = (1./m)*X*dZ'
-#db = (1./m)*np.sum(dZ)
-# w -= alpha*dw
-# b -= alpha*db