From 7b4f9d3fc47c998c31d47953bbe0ae3cac777516 Mon Sep 17 00:00:00 2001
From: Julien Gacon <gaconju@gmail.com>
Date: Mon, 4 Jul 2022 10:57:07 +0200
Subject: [PATCH] Fix ``maxfun`` default in ``L_BFGS``
 (Qiskit/qiskit-terra#8285)

* Fix maxfun and rm deprecated arg

* update docs, rm "epsilon"

* add reno

* lint

* update reno
---
 qiskit_algorithms/optimizers/l_bfgs_b.py | 23 +++++++++++------------
 1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/qiskit_algorithms/optimizers/l_bfgs_b.py b/qiskit_algorithms/optimizers/l_bfgs_b.py
index 1b5cf676..6b26ee80 100644
--- a/qiskit_algorithms/optimizers/l_bfgs_b.py
+++ b/qiskit_algorithms/optimizers/l_bfgs_b.py
@@ -16,7 +16,6 @@
 
 import numpy as np
 
-
 from .scipy_optimizer import SciPyOptimizer
 
 
@@ -39,7 +38,7 @@ class L_BFGS_B(SciPyOptimizer):  # pylint: disable=invalid-name
     and also to form an estimate of the Hessian matrix (second derivative) of :math:`f`.
     L-BFGS-B extends L-BFGS to handle simple, per-variable bound constraints.
 
-    Uses scipy.optimize.fmin_l_bfgs_b.
+    Uses ``scipy.optimize.fmin_l_bfgs_b``.
     For further detail, please refer to
     https://docs.scipy.org/doc/scipy/reference/optimize.minimize-lbfgsb.html
     """
@@ -49,10 +48,9 @@ class L_BFGS_B(SciPyOptimizer):  # pylint: disable=invalid-name
     # pylint: disable=unused-argument
     def __init__(
         self,
-        maxfun: int = 1000,
+        maxfun: int = 15000,
         maxiter: int = 15000,
         ftol: float = 10 * np.finfo(float).eps,
-        factr: Optional[float] = None,
         iprint: int = -1,
         eps: float = 1e-08,
         options: Optional[dict] = None,
@@ -63,17 +61,18 @@ def __init__(
         Args:
             maxfun: Maximum number of function evaluations.
             maxiter: Maximum number of iterations.
-            ftol: The iteration stops when (f\^k - f\^{k+1})/max{\|f\^k\|,\|f\^{k+1}\|,1} <= ftol.
-            iprint: Controls the frequency of output. iprint < 0 means no output;
-                iprint = 0 print only one line at the last iteration; 0 < iprint < 99
-                print also f and \|proj g\| every iprint iterations; iprint = 99 print
-                details of every iteration except n-vectors; iprint = 100 print also the
-                changes of active set and final x; iprint > 100 print details of
-                every iteration including x and g.
+            ftol: The iteration stops when
+                :math:`(f^k - f^{k+1}) / \max\{|f^k|, |f^{k+1}|,1\} \leq \text{ftol}`.
+            iprint: Controls the frequency of output. ``iprint < 0`` means no output;
+                ``iprint = 0`` print only one line at the last iteration; ``0 < iprint < 99``
+                print also :math:`f` and :math:`|\text{proj} g|` every iprint iterations;
+                ``iprint = 99`` print details of every iteration except n-vectors; ``iprint = 100``
+                print also the changes of active set and final :math:`x`; ``iprint > 100`` print
+                details of every iteration including :math:`x` and :math:`g`.
             eps: If jac is approximated, use this value for the step size.
             options: A dictionary of solver options.
             max_evals_grouped: Max number of default gradient evaluations performed simultaneously.
-            kwargs: additional kwargs for scipy.optimize.minimize.
+            kwargs: additional kwargs for ``scipy.optimize.minimize``.
         """
         if options is None:
             options = {}