input_sensitivity and ard plotting

GPy/kern/_src/add.py

@@ -83,7 +83,7 @@ class Add(Kern):
         from white import White
         from rbf import RBF
         #from rbf_inv import RBFInv
-        #from bias import Bias
+        from bias import Bias
         from linear import Linear
         #ffrom fixed import Fixed
 
@@ -131,11 +131,11 @@ class Add(Kern):
 
 
     def gradients_Z_variational(self, dL_dKmm, dL_dpsi0, dL_dpsi1, dL_dpsi2, mu, S, Z):
-        from white import white
-        from rbf import rbf
+        from white import White
+        from rbf import RBF
         #from rbf_inv import rbfinv
-        #from bias import bias
-        from linear import linear
+        from bias import Bias
+        from linear import Linear
         #ffrom fixed import fixed
 
         target = np.zeros(Z.shape)
@@ -146,15 +146,15 @@ class Add(Kern):
             for p2, is2 in zip(self._parameters_, self.input_slices):
                 if p2 is p1:
                     continue
-                if isinstance(p2, white):
+                if isinstance(p2, White):
                     continue
-                elif isinstance(p2, bias):
+                elif isinstance(p2, Bias):
                     eff_dL_dpsi1 += dL_dpsi2.sum(1) * p2.variance * 2.
                 else:
-                    eff_dL_dpsi1 += dL_dpsi2.sum(1) * p2.psi1(z[:,is2], mu[:,is2], s[:,is2]) * 2.
+                    eff_dL_dpsi1 += dL_dpsi2.sum(1) * p2.psi1(Z[:,is2], mu[:,is2], S[:,is2]) * 2.
 
 
-            target += p1.gradients_z_variational(dL_dkmm, dL_dpsi0, eff_dL_dpsi1, dL_dpsi2, mu[:,is1], s[:,is1], z[:,is1])
+            target += p1.gradients_z_variational(dL_dKmm, dL_dpsi0, eff_dL_dpsi1, dL_dpsi2, mu[:,is1], S[:,is1], Z[:,is1])
         return target
 
     def gradients_muS_variational(self, dL_dKmm, dL_dpsi0, dL_dpsi1, dL_dpsi2, mu, S, Z):
@@ -195,6 +195,12 @@ class Add(Kern):
         from ..plotting.matplot_dep import kernel_plots
         kernel_plots.plot(self,*args)
 
+    def input_sensitivity(self):
+        in_sen = np.zeros((self.input_dim, self.num_params))
+        for i, [p, i_s] in enumerate(zip(self._parameters_, self.input_slices)):
+            in_sen[i_s, i] = p.input_sensitivity()
+        return in_sen
+    
     def _getstate(self):
         """
         Get the current state of the class,

GPy/kern/_src/bias.py

@@ -28,12 +28,12 @@ class Bias(Kern):
         self.variance.gradient = dL_dK.sum()
 
     def update_gradients_diag(self, dL_dKdiag, X):
-        self.variance.gradient = dL_dK.sum()
+        self.variance.gradient = dL_dKdiag.sum()
 
-    def gradients_X(self, dL_dK,X, X2, target):
+    def gradients_X(self, dL_dK,X, X2):
         return np.zeros(X.shape)
 
-    def gradients_X_diag(self,dL_dKdiag,X,target):
+    def gradients_X_diag(self,dL_dKdiag,X):
         return np.zeros(X.shape)
 
 

GPy/kern/_src/kern.py

@@ -61,16 +61,20 @@ class Kern(Parameterized):
     def gradients_q_variational(self, dL_dKmm, dL_dpsi0, dL_dpsi1, dL_dpsi2, Z, posterior_variational):
         raise NotImplementedError
     
-    def plot_ARD(self, *args):
-        """If an ARD kernel is present, plot a bar representation using matplotlib
-
-        See GPy.plotting.matplot_dep.plot_ARD
-        """
+    def plot_ARD(self, *args, **kw):
+        if "matplotlib" in sys.modules:
+            from ...plotting.matplot_dep import kernel_plots
+            self.plot_ARD.__doc__ += kernel_plots.plot_ARD.__doc__
         assert "matplotlib" in sys.modules, "matplotlib package has not been imported."
         from ...plotting.matplot_dep import kernel_plots
-        return kernel_plots.plot_ARD(self,*args)
-
-
+        return kernel_plots.plot_ARD(self,*args,**kw)
+    
+    def input_sensitivity(self):
+        """
+        Returns the sensitivity for each dimension of this kernel.
+        """
+        return np.zeros(self.input_dim)
+    
     def __add__(self, other):
         """ Overloading of the '+' operator. for more control, see self.add """
         return self.add(other)

GPy/kern/_src/linear.py

@@ -252,3 +252,6 @@ class Linear(Kern):
 
         return np.dot(ZA, inner).swapaxes(0, 1)  # NOTE: self.ZAinner \in [num_inducing x N x input_dim]!
 
+    def input_sensitivity(self):
+        if self.ARD: return self.variances
+        else: return self.variances.repeat(self.input_dim)

GPy/kern/_src/rbf.py

@@ -382,3 +382,7 @@ class RBF(Kern):
                      type_converters=weave.converters.blitz, **self.weave_options)
 
         return mudist, mudist_sq, psi2_exponent, psi2
+
+    def input_sensitivity(self):
+        if self.ARD: return 1./self.lengthscale
+        else: return (1./self.lengthscale).repeat(self.input_dim)