From 49721d12b0faa489f7fea0a31b531ab2d46744fd Mon Sep 17 00:00:00 2001
From: Isuru Fernando <isuruf@gmail.com>
Date: Mon, 24 Jun 2019 20:12:08 +0200
Subject: [PATCH] Remove deriv multiplier
---
sumpy/expansion/__init__.py | 9 +++------
sumpy/expansion/pde_utils.py | 37 +-----------------------------------
sumpy/tools.py | 12 ------------
3 files changed, 4 insertions(+), 54 deletions(-)
diff --git a/sumpy/expansion/__init__.py b/sumpy/expansion/__init__.py
index 384fe64a..60f6eb5b 100644
--- a/sumpy/expansion/__init__.py
+++ b/sumpy/expansion/__init__.py
@@ -30,7 +30,7 @@ from pytools import memoize_method
import sumpy.symbolic as sym
from collections import defaultdict
from sumpy.tools import add_mi, find_linear_independent_row, CoeffIdentifier
-from .pde_utils import (make_pde_syms, process_pde, laplacian, div, grad,
+from .pde_utils import (make_pde_syms, laplacian, div, grad,
PDE)
__doc__ = """
@@ -485,7 +485,6 @@ class LinearPDEBasedExpansionTermsWrangler(ExpansionTermsWrangler):
from sumpy.tools import nullspace
pdes, iexpr, nexpr = self.get_pdes()
- pdes, multiplier = process_pde(pdes)
if nexpr == 1:
return pdes
@@ -523,11 +522,9 @@ class LinearPDEBasedExpansionTermsWrangler(ExpansionTermsWrangler):
indep_row = find_linear_independent_row(n)
if len(indep_row) > 0:
pde_dict = {}
- min_order = min(sum(mis[k]) for k in indep_row.keys())
+ mult = indep_row[max(indep_row.keys())]
for k, v in indep_row.items():
- mi = mis[k]
- mult = multiplier**(sum(mi)-min_order)
- pde_dict[CoeffIdentifier(mi, 0)] = v * mult
+ pde_dict[CoeffIdentifier(mis[k], 0)] = v / mult
plog.done()
return PDE(self.dim, pde_dict)
diff --git a/sumpy/expansion/pde_utils.py b/sumpy/expansion/pde_utils.py
index 23152e9a..34c669ac 100644
--- a/sumpy/expansion/pde_utils.py
+++ b/sumpy/expansion/pde_utils.py
@@ -23,8 +23,7 @@ THE SOFTWARE.
"""
from collections import defaultdict
-from sumpy.tools import CoeffIdentifier, add_mi, nth_root_assume_positive
-import sumpy.symbolic as sym
+from sumpy.tools import CoeffIdentifier, add_mi
class PDE(object):
@@ -152,40 +151,6 @@ def div(pde):
return PDE(pde.dim, dict(result))
-def process_pde(pde):
- """
- Process a PDE object to return a PDE and a multiplier such that
- the sum of multiplier ** order * derivative * coefficient gives the
- original PDE `pde`.
- """
- multiplier = None
- for eq in pde.eqs:
- for ident1, val1 in eq.items():
- for ident2, val2 in eq.items():
- s1 = sum(ident1.mi)
- s2 = sum(ident2.mi)
- if s1 == s2:
- continue
- m = nth_root_assume_positive(val1/val2, s2 - s1)
- if multiplier is None and not isinstance(m, (int, sym.Integer)):
- multiplier = m
-
- if multiplier is None:
- return pde, 1
- eqs = []
- for eq in pde.eqs:
- new_eq = dict()
- for i, (k, v) in enumerate(eq.items()):
- new_eq[k] = v * multiplier**sum(k.mi)
- if i == 0:
- val = new_eq[k]
- new_eq[k] /= sym.sympify(val)
- if isinstance(new_eq[k], sym.Integer):
- new_eq[k] = int(new_eq[k])
- eqs.append(new_eq)
- return PDE(pde.dim, *eqs), multiplier
-
-
def make_pde_syms(dim, nexprs):
"""
Returns a list of expressions of size `nexprs` to create a PDE
diff --git a/sumpy/tools.py b/sumpy/tools.py
index 38a021d4..345b176f 100644
--- a/sumpy/tools.py
+++ b/sumpy/tools.py
@@ -757,18 +757,6 @@ def solve_symbolic(A, b): # noqa: N803
CoeffIdentifier = namedtuple('CoeffIdentifier', ['mi', 'iexpr'])
-def nth_root_assume_positive(expr, n):
- """
- Get the nth root of a symbolic expression assuming that
- the symbols are positive.
- """
- expr = sym.sympify(expr)
- if expr.is_Pow:
- return expr.args[0] ** (expr.args[1] / sym.Integer(n))
- else:
- return expr ** (sym.Integer(1)/n)
-
-
def find_linear_independent_row(nullspace):
"""
This method does elementary row operations to figure out the first row
--
GitLab