[Yt-svn] yt: 5 new changesets

hg at spacepope.org hg at spacepope.org
Mon Apr 26 19:08:43 PDT 2010


hg Repository: yt
details:   yt/rev/02d9c851c577
changeset: 1612:02d9c851c577
user:      Matthew Turk <matthewturk at gmail.com>
date:
Mon Apr 26 13:12:04 2010 -0700
description:
Semi-functional quad-tree implementation.  Assumes RefineBy = 2 and doesn't
actually return points or de-allocate memory yet.  No checks for correctness
yet.  Takes a lot less time than old method of projecting, despite those
obvious caveats.

hg Repository: yt
details:   yt/rev/e1906cf72dac
changeset: 1613:e1906cf72dac
user:      Matthew Turk <matthewturk at gmail.com>
date:
Mon Apr 26 13:38:05 2010 -0700
description:
Adding deallocation method

hg Repository: yt
details:   yt/rev/ec26f1610e76
changeset: 1614:ec26f1610e76
user:      Matthew Turk <matthewturk at gmail.com>
date:
Mon Apr 26 14:33:55 2010 -0700
description:
Fixing the addition and counting mechanisms.  Quad tree now returns the correct
number of points per level, as compared to the old projection mechanism.

hg Repository: yt
details:   yt/rev/d4984db3c66f
changeset: 1615:d4984db3c66f
user:      Matthew Turk <matthewturk at gmail.com>
date:
Mon Apr 26 16:37:22 2010 -0700
description:
Nearing a working quadtree implementation.

hg Repository: yt
details:   yt/rev/dd182310083e
changeset: 1616:dd182310083e
user:      Matthew Turk <matthewturk at gmail.com>
date:
Mon Apr 26 19:07:11 2010 -0700
description:
Adding QuadTree to amr_utils.pyx.

diffstat:

 yt/_amr_utils/QuadTree.pyx |  257 ++++++++++++++++++++++++++++++++++++++++++
 yt/amr_utils.pyx           |    1 +
 2 files changed, 258 insertions(+), 0 deletions(-)

diffs (269 lines):

diff -r c7169b1b4c66 -r dd182310083e yt/_amr_utils/QuadTree.pyx
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/yt/_amr_utils/QuadTree.pyx	Mon Apr 26 19:07:11 2010 -0700
@@ -0,0 +1,257 @@
+"""
+A refine-by-two AMR-specific quadtree
+
+Author: Matthew Turk <matthewturk at gmail.com>
+Affiliation: UCSD
+Homepage: http://yt.enzotools.org/
+License:
+  Copyright (C) 2010 Matthew Turk.  All Rights Reserved.
+
+  This file is part of yt.
+
+  yt is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 3 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
+
+import numpy as np
+cimport numpy as np
+# Double up here for def'd functions
+cimport numpy as cnp
+cimport cython
+
+from stdlib cimport malloc, free, abs
+
+cdef extern from "stdlib.h":
+    # NOTE that size_t might not be int
+    void *alloca(int)
+
+cdef struct QuadTreeNode:
+    np.float64_t *val
+    np.float64_t weight_val
+    np.int64_t pos[2]
+    int level
+    int nvals
+    QuadTreeNode *children[2][2]
+
+cdef void QTN_add_value(QuadTreeNode *self,
+        np.float64_t *val, np.float64_t weight_val):
+    cdef int i
+    for i in range(self.nvals):
+        self.val[i] += val[i]
+    self.weight_val += weight_val
+
+cdef void QTN_refine(QuadTreeNode *self):
+    cdef int i, j, i1, j1
+    cdef np.int64_t npos[2]
+    cdef QuadTreeNode *node
+    for i in range(2):
+        npos[0] = self.pos[0] * 2 + i
+        for j in range(2):
+            npos[1] = self.pos[1] * 2 + j
+            # We have to be careful with allocation...
+            self.children[i][j] = QTN_initialize(
+                        npos,
+                        self.nvals, self.val, self.weight_val,
+                        self.level + 1)
+    for i in range(self.nvals): self.val[i] = 0.0
+    self.weight_val = 0.0
+
+cdef QuadTreeNode *QTN_initialize(np.int64_t pos[2], int nvals,
+                        np.float64_t *val, np.float64_t weight_val,
+                        int level):
+    cdef QuadTreeNode *node
+    cdef int i, j
+    node = <QuadTreeNode *> malloc(sizeof(QuadTreeNode))
+    node.pos[0] = pos[0]
+    node.pos[1] = pos[1]
+    node.nvals = nvals
+    node.val = <np.float64_t *> malloc(
+                nvals * sizeof(np.float64_t))
+    for i in range(nvals):
+        node.val[i] = val[i]
+    node.weight_val = weight_val
+    for i in range(2):
+        for j in range(2):
+            node.children[i][j] = NULL
+    node.level = level
+    return node
+
+cdef void QTN_free(QuadTreeNode *node):
+    cdef int i, j
+    for i in range(2):
+        for j in range(2):
+            if node.children[i][j] == NULL: continue
+            QTN_free(node.children[i][j])
+    free(node.val)
+    free(node)
+
+cdef class QuadTree:
+    cdef int nvals
+    cdef np.int64_t po2[80]
+    cdef QuadTreeNode ***root_nodes
+    cdef np.int64_t top_grid_dims[2]
+
+    def __cinit__(self, np.ndarray[np.int64_t, ndim=1] top_grid_dims,
+                  int nvals):
+        cdef int i, j
+        cdef QuadTreeNode *node
+        cdef np.int64_t pos[2]
+        cdef np.float64_t *vals = <np.float64_t *> alloca(
+                sizeof(np.float64_t)*nvals)
+        cdef np.float64_t weight_val = 0.0
+        self.nvals = nvals
+        for i in range(nvals): vals[i] = 0.0
+
+        self.top_grid_dims[0] = top_grid_dims[0]
+        self.top_grid_dims[1] = top_grid_dims[1]
+
+        # This wouldn't be necessary if we did bitshifting...
+        for i in range(80):
+            self.po2[i] = 2**i
+        self.root_nodes = <QuadTreeNode ***> \
+            malloc(sizeof(QuadTreeNode **) * top_grid_dims[0])
+
+        # We initialize our root values to 0.0.
+        for i in range(top_grid_dims[0]):
+            pos[0] = i
+            self.root_nodes[i] = <QuadTreeNode **> \
+                malloc(sizeof(QuadTreeNode *) * top_grid_dims[1])
+            for j in range(top_grid_dims[1]):
+                pos[1] = j
+                self.root_nodes[i][j] = QTN_initialize(
+                    pos, nvals, vals, weight_val, 0)
+
+    cdef void add_to_position(self,
+                 int level, np.int64_t pos[2],
+                 np.float64_t *val,
+                 np.float64_t weight_val):
+        cdef int i, j
+        cdef QuadTreeNode *node
+        node = self.find_on_root_level(pos, level)
+        cdef np.int64_t fac
+        for L in range(level):
+            if node.children[0][0] == NULL:
+                QTN_refine(node)
+            # Maybe we should use bitwise operators?
+            fac = self.po2[level - L - 1]
+            i = (pos[0] >= fac*(2*node.pos[0]+1))
+            j = (pos[1] >= fac*(2*node.pos[1]+1))
+            node = node.children[i][j]
+        QTN_add_value(node, val, weight_val)
+            
+    cdef QuadTreeNode *find_on_root_level(self, np.int64_t pos[2], int level):
+        # We need this because the root level won't just have four children
+        # So we find on the root level, then we traverse the tree.
+        cdef np.int64_t i, j
+        i = <np.int64_t> (pos[0] / self.po2[level])
+        j = <np.int64_t> (pos[1] / self.po2[level])
+        return self.root_nodes[i][j]
+        
+    
+    @cython.boundscheck(False)
+    @cython.wraparound(False)
+    def add_array_to_tree(self, int level,
+            np.ndarray[np.int64_t, ndim=1] pxs,
+            np.ndarray[np.int64_t, ndim=1] pys,
+            np.ndarray[np.float64_t, ndim=2] pvals,
+            np.ndarray[np.float64_t, ndim=1] pweight_vals):
+        cdef int np = pxs.shape[0]
+        cdef int p
+        cdef cnp.float64_t *vals
+        cdef cnp.float64_t *data = <cnp.float64_t *> pvals.data
+        cdef cnp.int64_t pos[2]
+        for p in range(np):
+            vals = data + self.nvals*p
+            pos[0] = pxs[p]
+            pos[1] = pys[p]
+            self.add_to_position(level, pos, vals, pweight_vals[p])
+
+    def add_grid_to_tree(self, int level,
+                         np.ndarray[np.int64_t, ndim=1] start_index,
+                         np.ndarray[np.float64_t, ndim=2] pvals,
+                         np.ndarray[np.float64_t, ndim=2] wvals,
+                         np.ndarray[np.int32_t, ndim=2] cm):
+        pass
+
+    @cython.boundscheck(False)
+    @cython.wraparound(False)
+    def get_all_from_level(self, int level, int count_only = 0):
+        cdef int i, j
+        cdef int total = 0
+        vals = []
+        for i in range(self.top_grid_dims[0]):
+            for j in range(self.top_grid_dims[1]):
+                total += self.count_at_level(self.root_nodes[i][j], level)
+        if count_only: return total
+        # Allocate our array
+        cdef np.ndarray[np.int64_t, ndim=2] npos
+        cdef np.ndarray[np.float64_t, ndim=2] nvals
+        cdef np.ndarray[np.float64_t, ndim=1] nwvals
+        npos = np.zeros( (total, 2), dtype='int64')
+        nvals = np.zeros( (total, self.nvals), dtype='float64')
+        nwvals = np.zeros( total, dtype='float64')
+        cdef np.int64_t curpos = 0
+        cdef np.int64_t *pdata = <np.int64_t *> npos.data
+        cdef np.float64_t *vdata = <np.float64_t *> nvals.data
+        cdef np.float64_t *wdata = <np.float64_t *> nwvals.data
+        for i in range(self.top_grid_dims[0]):
+            for j in range(self.top_grid_dims[1]):
+                curpos += self.fill_from_level(self.root_nodes[i][j],
+                    level, curpos, pdata, vdata, wdata)
+        return npos, nvals, nwvals
+
+    cdef int count_at_level(self, QuadTreeNode *node, int level):
+        cdef int i, j
+        # We only really return a non-zero, calculated value if we are at the
+        # level in question.
+        if node.level == level:
+            # We return 1 if there are no finer points at this level and zero
+            # if there are
+            return (node.children[0][0] == NULL)
+        if node.children[0][0] == NULL: return 0
+        cdef int count = 0
+        for i in range(2):
+            for j in range(2):
+                count += self.count_at_level(node.children[i][j], level)
+        return count
+
+    cdef int fill_from_level(self, QuadTreeNode *node, int level,
+                              np.int64_t curpos,
+                              np.int64_t *pdata,
+                              np.float64_t *vdata,
+                              np.float64_t *wdata):
+        cdef int i, j
+        if node.level == level:
+            if node.children[0][0] != NULL: return 0
+            for i in range(self.nvals):
+                vdata[self.nvals * curpos + i] = node.val[i]
+            wdata[curpos] = node.weight_val
+            pdata[curpos * 2] = node.pos[0]
+            pdata[curpos * 2 + 1] = node.pos[1]
+            return 1
+        if node.children[0][0] == NULL: return 0
+        cdef np.int64_t added = 0
+        for i in range(2):
+            for j in range(2):
+                added += self.fill_from_level(node.children[i][j],
+                        level, curpos + added, pdata, vdata, wdata)
+        return added
+
+    def __dealloc__(self):
+        cdef int i, j
+        for i in range(self.top_grid_dims[0]):
+            for j in range(self.top_grid_dims[1]):
+                QTN_free(self.root_nodes[i][j])
+            free(self.root_nodes[i])
+        free(self.root_nodes)
diff -r c7169b1b4c66 -r dd182310083e yt/amr_utils.pyx
--- a/yt/amr_utils.pyx	Mon Apr 26 09:57:45 2010 -0700
+++ b/yt/amr_utils.pyx	Mon Apr 26 19:07:11 2010 -0700
@@ -44,3 +44,4 @@
 include "_amr_utils/ContourFinding.pyx"
 include "_amr_utils/png_writer.pyx"
 include "_amr_utils/fortran_reader.pyx"
+include "_amr_utils/QuadTree.pyx"



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