From 981351165dbab740145d109b00782f0c41f2244b Mon Sep 17 00:00:00 2001
From: Rémi Flamary <remi.flamary@gmail.com>
Date: Wed, 2 Nov 2016 17:13:43 +0100
Subject: add mapping estimation (still debugging)

---
 ot/optim.py | 106 ++++++++++++++++++++++++++++++------------------------------
 1 file changed, 53 insertions(+), 53 deletions(-)

(limited to 'ot/optim.py')

diff --git a/ot/optim.py b/ot/optim.py
index 1afbea3..dcefd24 100644
--- a/ot/optim.py
+++ b/ot/optim.py
@@ -12,21 +12,21 @@ from .lp import emd
 def line_search_armijo(f,xk,pk,gfk,old_fval,args=(),c1=1e-4,alpha0=0.99):
     """
     Armijo linesearch function that works with matrices
-    
-    find an approximate minimum of f(xk+alpha*pk) that satifies the 
-    armijo conditions. 
-    
+
+    find an approximate minimum of f(xk+alpha*pk) that satifies the
+    armijo conditions.
+
     Parameters
     ----------
 
     f : function
         loss function
-    xk : np.ndarray 
+    xk : np.ndarray
         initial position
-    pk : np.ndarray 
+    pk : np.ndarray
         descent direction
     gfk : np.ndarray
-        gradient of f at xk        
+        gradient of f at xk
     old_fval: float
         loss value at xk
     args : tuple, optional
@@ -35,7 +35,7 @@ def line_search_armijo(f,xk,pk,gfk,old_fval,args=(),c1=1e-4,alpha0=0.99):
         c1 const in armijo rule (>0)
     alpha0 : float, optional
         initial step (>0)
-  
+
     Returns
     -------
     alpha : float
@@ -44,49 +44,49 @@ def line_search_armijo(f,xk,pk,gfk,old_fval,args=(),c1=1e-4,alpha0=0.99):
         nb of function call
     fa : float
         loss value at step alpha
-    
+
     """
     xk = np.atleast_1d(xk)
     fc = [0]
-    
+
     def phi(alpha1):
         fc[0] += 1
         return f(xk + alpha1*pk, *args)
-    
+
     if old_fval is None:
         phi0 = phi(0.)
     else:
         phi0 = old_fval
-    
+
     derphi0 = np.sum(pk*gfk) # Quickfix for matrices
     alpha,phi1 = scalar_search_armijo(phi,phi0,derphi0,c1=c1,alpha0=alpha0)
-    
+
     return alpha,fc[0],phi1
 
 
 def cg(a,b,M,reg,f,df,G0=None,numItermax = 200,stopThr=1e-9,verbose=False,log=False):
     """
     Solve the general regularized OT problem with conditional gradient
-    
+
         The function solves the following optimization problem:
-    
+
     .. math::
         \gamma = arg\min_\gamma <\gamma,M>_F + reg*f(\gamma)
-        
+
         s.t. \gamma 1 = a
-        
-             \gamma^T 1= b 
-             
+
+             \gamma^T 1= b
+
              \gamma\geq 0
     where :
-    
+
     - M is the (ns,nt) metric cost matrix
     - :math:`f` is the regularization term ( and df is its gradient)
     - a and b are source and target weights (sum to 1)
-    
+
     The algorithm used for solving the problem is conditional gradient as discussed in  [1]_
-    
-             
+
+
     Parameters
     ----------
     a : np.ndarray (ns,)
@@ -94,7 +94,7 @@ def cg(a,b,M,reg,f,df,G0=None,numItermax = 200,stopThr=1e-9,verbose=False,log=Fa
     b : np.ndarray (nt,)
         samples in the target domain
     M : np.ndarray (ns,nt)
-        loss matrix        
+        loss matrix
     reg : float
         Regularization term >0
     G0 :  np.ndarray (ns,nt), optional
@@ -107,87 +107,87 @@ def cg(a,b,M,reg,f,df,G0=None,numItermax = 200,stopThr=1e-9,verbose=False,log=Fa
         Print information along iterations
     log : bool, optional
         record log if True
-    
+
     Returns
     -------
     gamma: (ns x nt) ndarray
         Optimal transportation matrix for the given parameters
     log: dict
-        log dictionary return only if log==True in parameters 
-    
-        
+        log dictionary return only if log==True in parameters
+
+
     References
     ----------
-    
+
     .. [1] Ferradans, S., Papadakis, N., Peyré, G., & Aujol, J. F. (2014). Regularized discrete optimal transport. SIAM Journal on Imaging Sciences, 7(3), 1853-1882.
-        
+
     See Also
     --------
     ot.lp.emd : Unregularized optimal ransport
     ot.bregman.sinkhorn : Entropic regularized optimal transport
-           
+
     """
-    
+
     loop=1
-    
+
     if log:
         log={'loss':[]}
-    
+
     if G0 is None:
         G=np.outer(a,b)
     else:
         G=G0
-    
+
     def cost(G):
         return np.sum(M*G)+reg*f(G)
-        
+
     f_val=cost(G)
     if log:
         log['loss'].append(f_val)
-    
+
     it=0
-    
+
     if verbose:
         print('{:5s}|{:12s}|{:8s}'.format('It.','Loss','Delta loss')+'\n'+'-'*32)
         print('{:5d}|{:8e}|{:8e}'.format(it,f_val,0))
-    
+
     while loop:
-        
+
         it+=1
         old_fval=f_val
-        
-        
+
+
         # problem linearization
         Mi=M+reg*df(G)
-        
+
         # solve linear program
         Gc=emd(a,b,Mi)
-        
+
         deltaG=Gc-G
-        
+
         # line search
         alpha,fc,f_val = line_search_armijo(cost,G,deltaG,Mi,f_val)
-        
+
         G=G+alpha*deltaG
-        
+
         # test convergence
         if it>=numItermax:
             loop=0
-        
+
         delta_fval=(f_val-old_fval)/abs(f_val)
         if abs(delta_fval)<stopThr:
             loop=0
-            
-        
+
+
         if log:
-            log['loss'].append(f_val)        
-        
+            log['loss'].append(f_val)
+
         if verbose:
             if it%20 ==0:
                 print('{:5s}|{:12s}|{:8s}'.format('It.','Loss','Delta loss')+'\n'+'-'*32)
             print('{:5d}|{:8e}|{:8e}'.format(it,f_val,delta_fval))
 
-    
+
     if log:
         return G,log
     else:
-- 
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