Fix Visual for hill_saturation function (Issue pymc-labs#851 ) (pymc…

…-labs#857)

* Fix plotting by evaluating tensors.

* Add space after sphinx directive.

* Remove indentation from blank line.

* Add shared y axis for subplots.

---------

Co-authored-by: Patrick Robotham <[email protected]>
Co-authored-by: Will Dean <[email protected]>

pymc_marketing/mmm/transformers.py

@@ -924,47 +924,50 @@ def hill_saturation(
 
     .. plot::
         :context: close-figs
+
         import numpy as np
         import matplotlib.pyplot as plt
         from pymc_marketing.mmm.transformers import hill_saturation
         x = np.linspace(0, 10, 100)
         # Varying sigma
         sigmas = [0.5, 1, 1.5]
-        plt.figure(figsize=(12, 4))
+        fig, axes = plt.subplots(1, 3, figsize=(12, 4), sharey=True)
         for i, sigma in enumerate(sigmas):
             plt.subplot(1, 3, i+1)
-            y = hill_saturation(x, sigma, 2, 5)
+            y = hill_saturation(x, sigma, 2, 5).eval()
             plt.plot(x, y)
             plt.xlabel('x')
-            plt.ylabel('Hill Saturation')
             plt.title(f'Sigma = {sigma}')
+        plt.subplot(1,3,1)
+        plt.ylabel('Hill Saturation')
         plt.tight_layout()
         plt.show()
         # Varying beta
         betas = [1, 2, 3]
-        plt.figure(figsize=(12, 4))
+        fig, axes = plt.subplots(1, 3, figsize=(12, 4), sharey=True)
         for i, beta in enumerate(betas):
             plt.subplot(1, 3, i+1)
-            y = hill_saturation(x, 1, beta, 5)
+            y = hill_saturation(x, 1, beta, 5).eval()
             plt.plot(x, y)
             plt.xlabel('x')
-            plt.ylabel('Hill Saturation')
             plt.title(f'Beta = {beta}')
+        plt.subplot(1,3,1)
+        plt.ylabel('Hill Saturation')
         plt.tight_layout()
         plt.show()
         # Varying lam
         lams = [3, 5, 7]
-        plt.figure(figsize=(12, 4))
+        fig, axes = plt.subplots(1, 3, figsize=(12, 4), sharey=True)
         for i, lam in enumerate(lams):
             plt.subplot(1, 3, i+1)
-            y = hill_saturation(x, 1, 2, lam)
+            y = hill_saturation(x, 1, 2, lam).eval()
             plt.plot(x, y)
             plt.xlabel('x')
-            plt.ylabel('Hill Saturation')
             plt.title(f'Lambda = {lam}')
+        plt.subplot(1,3,1)
+        plt.ylabel('Hill Saturation')
         plt.tight_layout()
         plt.show()
-
     Parameters
     ----------
     x : float or array-like