Source code for yt.geometry.grid_geometry_handler

import abc
import weakref
from collections import defaultdict

import numpy as np

from yt.arraytypes import blankRecordArray
from yt.config import ytcfg
from yt.fields.derived_field import ValidateSpatial
from yt.fields.field_detector import FieldDetector
from yt.funcs import ensure_numpy_array, iter_fields
from yt.geometry.geometry_handler import ChunkDataCache, Index, YTDataChunk
from yt.utilities.definitions import MAXLEVEL
from yt.utilities.logger import ytLogger as mylog

from .grid_container import GridTree, MatchPointsToGrids


[docs] class GridIndex(Index, abc.ABC): """The index class for patch and block AMR datasets.""" float_type = "float64" _preload_implemented = False _index_properties = ( "grid_left_edge", "grid_right_edge", "grid_levels", "grid_particle_count", "grid_dimensions", ) def _setup_geometry(self): mylog.debug("Counting grids.") self._count_grids() mylog.debug("Initializing grid arrays.") self._initialize_grid_arrays() mylog.debug("Parsing index.") self._parse_index() mylog.debug("Constructing grid objects.") self._populate_grid_objects() mylog.debug("Re-examining index") self._initialize_level_stats() @abc.abstractmethod def _count_grids(self): pass @abc.abstractmethod def _parse_index(self): pass @abc.abstractmethod def _populate_grid_objects(self): pass def __del__(self): del self.grid_dimensions del self.grid_left_edge del self.grid_right_edge del self.grid_levels del self.grid_particle_count del self.grids @property def parameters(self): return self.dataset.parameters def _detect_output_fields_backup(self): # grab fields from backup file as well, if present return
[docs] def select_grids(self, level): """ Returns an array of grids at *level*. """ return self.grids[self.grid_levels.flat == level]
[docs] def get_levels(self): for level in range(self.max_level + 1): yield self.select_grids(level)
def _initialize_grid_arrays(self): mylog.debug("Allocating arrays for %s grids", self.num_grids) self.grid_dimensions = np.ones((self.num_grids, 3), "int32") self.grid_left_edge = self.ds.arr( np.zeros((self.num_grids, 3), self.float_type), "code_length" ) self.grid_right_edge = self.ds.arr( np.ones((self.num_grids, 3), self.float_type), "code_length" ) self.grid_levels = np.zeros((self.num_grids, 1), "int32") self.grid_particle_count = np.zeros((self.num_grids, 1), "int32")
[docs] def clear_all_data(self): """ This routine clears all the data currently being held onto by the grids and the data io handler. """ for g in self.grids: g.clear_data() self.io.queue.clear()
[docs] def get_smallest_dx(self): """ Returns (in code units) the smallest cell size in the simulation. """ return self.select_grids(self.grid_levels.max())[0].dds[:].min()
def _get_particle_type_counts(self): return {self.ds.particle_types_raw[0]: self.grid_particle_count.sum()} def _initialize_level_stats(self): # Now some statistics: # 0 = number of grids # 1 = number of cells # 2 = blank desc = {"names": ["numgrids", "numcells", "level"], "formats": ["int64"] * 3} self.level_stats = blankRecordArray(desc, MAXLEVEL) self.level_stats["level"] = list(range(MAXLEVEL)) self.level_stats["numgrids"] = [0 for i in range(MAXLEVEL)] self.level_stats["numcells"] = [0 for i in range(MAXLEVEL)] for level in range(self.max_level + 1): self.level_stats[level]["numgrids"] = np.sum(self.grid_levels == level) li = self.grid_levels[:, 0] == level self.level_stats[level]["numcells"] = ( self.grid_dimensions[li, :].prod(axis=1).sum() ) @property def grid_corners(self): return np.array( [ [ self.grid_left_edge[:, 0], self.grid_left_edge[:, 1], self.grid_left_edge[:, 2], ], [ self.grid_right_edge[:, 0], self.grid_left_edge[:, 1], self.grid_left_edge[:, 2], ], [ self.grid_right_edge[:, 0], self.grid_right_edge[:, 1], self.grid_left_edge[:, 2], ], [ self.grid_left_edge[:, 0], self.grid_right_edge[:, 1], self.grid_left_edge[:, 2], ], [ self.grid_left_edge[:, 0], self.grid_left_edge[:, 1], self.grid_right_edge[:, 2], ], [ self.grid_right_edge[:, 0], self.grid_left_edge[:, 1], self.grid_right_edge[:, 2], ], [ self.grid_right_edge[:, 0], self.grid_right_edge[:, 1], self.grid_right_edge[:, 2], ], [ self.grid_left_edge[:, 0], self.grid_right_edge[:, 1], self.grid_right_edge[:, 2], ], ], dtype="float64", )
[docs] def lock_grids_to_parents(self): r"""This function locks grid edges to their parents. This is useful in cases where the grid structure may be somewhat irregular, or where setting the left and right edges is a lossy process. It is designed to correct situations where left/right edges may be set slightly incorrectly, resulting in discontinuities in images and the like. """ mylog.info("Locking grids to parents.") for i, g in enumerate(self.grids): si = g.get_global_startindex() g.LeftEdge = self.ds.domain_left_edge + g.dds * si g.RightEdge = g.LeftEdge + g.ActiveDimensions * g.dds self.grid_left_edge[i, :] = g.LeftEdge self.grid_right_edge[i, :] = g.RightEdge
[docs] def print_stats(self): """ Prints out (stdout) relevant information about the simulation """ header = "{:>3}\t{:>6}\t{:>14}\t{:>14}".format( "level", "# grids", "# cells", "# cells^3" ) print(header) print(f"{len(header.expandtabs()) * '-'}") for level in range(MAXLEVEL): if (self.level_stats["numgrids"][level]) == 0: continue print( "% 3i\t% 6i\t% 14i\t% 14i" % ( level, self.level_stats["numgrids"][level], self.level_stats["numcells"][level], np.ceil(self.level_stats["numcells"][level] ** (1.0 / 3)), ) ) dx = self.select_grids(level)[0].dds[0] print("-" * 46) print( " \t% 6i\t% 14i" % (self.level_stats["numgrids"].sum(), self.level_stats["numcells"].sum()) ) print("\n") try: print(f"z = {self['CosmologyCurrentRedshift']:0.8f}") except Exception: pass print( "t = {:0.8e} = {:0.8e} = {:0.8e}".format( self.ds.current_time.in_units("code_time"), self.ds.current_time.in_units("s"), self.ds.current_time.in_units("yr"), ) ) print("\nSmallest Cell:") for item in ("Mpc", "pc", "AU", "cm"): print(f"\tWidth: {dx.in_units(item):0.3e}")
def _find_field_values_at_points(self, fields, coords): r"""Find the value of fields at a set of coordinates. Returns the values [field1, field2,...] of the fields at the given (x, y, z) points. Returns a numpy array of field values cross coords """ coords = self.ds.arr(ensure_numpy_array(coords), "code_length") grids = self._find_points(coords[:, 0], coords[:, 1], coords[:, 2])[0] fields = list(iter_fields(fields)) mark = np.zeros(3, dtype="int64") out = [] # create point -> grid mapping grid_index = {} for coord_index, grid in enumerate(grids): if grid not in grid_index: grid_index[grid] = [] grid_index[grid].append(coord_index) out = [] for field in fields: funit = self.ds._get_field_info(field).units out.append(self.ds.arr(np.empty(len(coords)), funit)) for grid in grid_index: cellwidth = (grid.RightEdge - grid.LeftEdge) / grid.ActiveDimensions for field_index, field in enumerate(fields): for coord_index in grid_index[grid]: mark = (coords[coord_index, :] - grid.LeftEdge) / cellwidth mark = np.array(mark, dtype="int64") out[field_index][coord_index] = grid[field][ mark[0], mark[1], mark[2] ] if len(fields) == 1: return out[0] return out def _find_points(self, x, y, z): """ Returns the (objects, indices) of leaf grids containing a number of (x,y,z) points """ x = ensure_numpy_array(x) y = ensure_numpy_array(y) z = ensure_numpy_array(z) if not len(x) == len(y) == len(z): raise ValueError("Arrays of indices must be of the same size") grid_tree = self._get_grid_tree() pts = MatchPointsToGrids(grid_tree, len(x), x, y, z) ind = pts.find_points_in_tree() return self.grids[ind], ind def _get_grid_tree(self): left_edge = self.ds.arr(np.zeros((self.num_grids, 3)), "code_length") right_edge = self.ds.arr(np.zeros((self.num_grids, 3)), "code_length") level = np.zeros((self.num_grids), dtype="int64") parent_ind = np.zeros((self.num_grids), dtype="int64") num_children = np.zeros((self.num_grids), dtype="int64") dimensions = np.zeros((self.num_grids, 3), dtype="int32") for i, grid in enumerate(self.grids): left_edge[i, :] = grid.LeftEdge right_edge[i, :] = grid.RightEdge level[i] = grid.Level if grid.Parent is None: parent_ind[i] = -1 else: parent_ind[i] = grid.Parent.id - grid.Parent._id_offset num_children[i] = np.int64(len(grid.Children)) dimensions[i, :] = grid.ActiveDimensions return GridTree( self.num_grids, left_edge, right_edge, dimensions, parent_ind, level, num_children, )
[docs] def convert(self, unit): return self.dataset.conversion_factors[unit]
def _identify_base_chunk(self, dobj): fast_index = None if dobj._type_name == "grid": dobj._chunk_info = np.empty(1, dtype="object") dobj._chunk_info[0] = weakref.proxy(dobj) elif getattr(dobj, "_grids", None) is None: gi = dobj.selector.select_grids( self.grid_left_edge, self.grid_right_edge, self.grid_levels ) if any(g.filename is not None for g in self.grids[gi]): _gsort = _grid_sort_mixed else: _gsort = _grid_sort_id grids = sorted(self.grids[gi], key=_gsort) dobj._chunk_info = np.empty(len(grids), dtype="object") for i, g in enumerate(grids): dobj._chunk_info[i] = g # These next two lines, when uncommented, turn "on" the fast index. # if dobj._type_name != "grid": # fast_index = self._get_grid_tree() if getattr(dobj, "size", None) is None: dobj.size = self._count_selection(dobj, fast_index=fast_index) if getattr(dobj, "shape", None) is None: dobj.shape = (dobj.size,) dobj._current_chunk = list( self._chunk_all(dobj, cache=False, fast_index=fast_index) )[0] def _count_selection(self, dobj, grids=None, fast_index=None): if fast_index is not None: return fast_index.count(dobj.selector) if grids is None: grids = dobj._chunk_info count = sum(g.count(dobj.selector) for g in grids) return count def _chunk_all(self, dobj, cache=True, fast_index=None): gobjs = getattr(dobj._current_chunk, "objs", dobj._chunk_info) fast_index = fast_index or getattr(dobj._current_chunk, "_fast_index", None) yield YTDataChunk(dobj, "all", gobjs, dobj.size, cache, fast_index=fast_index) def _chunk_spatial(self, dobj, ngz, sort=None, preload_fields=None): gobjs = getattr(dobj._current_chunk, "objs", dobj._chunk_info) if sort in ("+level", "level"): giter = sorted(gobjs, key=lambda g: g.Level) elif sort == "-level": giter = sorted(gobjs, key=lambda g: -g.Level) elif sort is None: giter = gobjs if preload_fields is None: preload_fields = [] preload_fields, _ = self._split_fields(preload_fields) if self._preload_implemented and len(preload_fields) > 0 and ngz == 0: giter = ChunkDataCache(list(giter), preload_fields, self) for og in giter: if ngz > 0: g = og.retrieve_ghost_zones(ngz, [], smoothed=True) else: g = og size = self._count_selection(dobj, [og]) if size == 0: continue # We don't want to cache any of the masks or icoords or fcoords for # individual grids. yield YTDataChunk(dobj, "spatial", [g], size, cache=False) _grid_chunksize = 1000 def _chunk_io( self, dobj, cache=True, local_only=False, preload_fields=None, chunk_sizing="auto", ): # local_only is only useful for inline datasets and requires # implementation by subclasses. if preload_fields is None: preload_fields = [] preload_fields, _ = self._split_fields(preload_fields) gfiles = defaultdict(list) gobjs = getattr(dobj._current_chunk, "objs", dobj._chunk_info) fast_index = dobj._current_chunk._fast_index for g in gobjs: # Force to be a string because sometimes g.filename is None. gfiles[str(g.filename)].append(g) # We can apply a heuristic here to make sure we aren't loading too # many grids all at once. if chunk_sizing == "auto": chunk_ngrids = len(gobjs) if chunk_ngrids > 0: nproc = int(ytcfg.get("yt", "internals", "global_parallel_size")) chunking_factor = np.int64( np.ceil(self._grid_chunksize * nproc / chunk_ngrids) ) size = max(self._grid_chunksize // chunking_factor, 1) else: size = self._grid_chunksize elif chunk_sizing == "config_file": size = ytcfg.get("yt", "chunk_size") elif chunk_sizing == "just_one": size = 1 elif chunk_sizing == "old": size = self._grid_chunksize else: raise RuntimeError( f"{chunk_sizing} is an invalid value for the 'chunk_sizing' argument." ) for fn in sorted(gfiles): gs = gfiles[fn] for grids in (gs[pos : pos + size] for pos in range(0, len(gs), size)): dc = YTDataChunk( dobj, "io", grids, self._count_selection(dobj, grids), cache=cache, fast_index=fast_index, ) # We allow four full chunks to be included. with self.io.preload(dc, preload_fields, 4.0 * size): yield dc def _icoords_to_fcoords( self, icoords: np.ndarray, ires: np.ndarray, axes: tuple[int, ...] | None = None, ) -> tuple[np.ndarray, np.ndarray]: """ Accepts icoords and ires and returns appropriate fcoords and fwidth. Mostly useful for cases where we have irregularly spaced or structured grids. """ dds = self.ds.domain_width[axes,] / ( self.ds.domain_dimensions[axes,] * self.ds.refine_by ** ires[:, None] ) pos = (0.5 + icoords) * dds + self.ds.domain_left_edge[axes,] return pos, dds def _add_mesh_sampling_particle_field(self, deposit_field, ftype, ptype): units = self.ds.field_info[ftype, deposit_field].units take_log = self.ds.field_info[ftype, deposit_field].take_log field_name = f"cell_{ftype}_{deposit_field}" def _mesh_sampling_particle_field(field, data): pos = data[ptype, "particle_position"] field_values = data[ftype, deposit_field] if isinstance(data, FieldDetector): return np.zeros(pos.shape[0]) i, j, k = np.floor((pos - data.LeftEdge) / data.dds).astype("int64").T # Make sure all particles are within the current grid, otherwise return nan maxi, maxj, maxk = field_values.shape mask = (i < maxi) & (j < maxj) & (k < maxk) mask &= (i >= 0) & (j >= 0) & (k >= 0) result = np.full(len(pos), np.nan, dtype="float64") if result.shape[0] > 0: result[mask] = field_values[i[mask], j[mask], k[mask]] return data.ds.arr(result, field_values.units) self.ds.add_field( (ptype, field_name), function=_mesh_sampling_particle_field, sampling_type="particle", units=units, take_log=take_log, validators=[ValidateSpatial()], )
def _grid_sort_id(g): return g.id def _grid_sort_mixed(g): if g.filename is None: return str(g.id) return g.filename