Source code for geometry

#
##
##  This file is part of pyFormex 1.0.7  (Mon Jun 17 12:20:39 CEST 2019)
##  pyFormex is a tool for generating, manipulating and transforming 3D
##  geometrical models by sequences of mathematical operations.
##  Home page: http://pyformex.org
##  Project page:  http://savannah.nongnu.org/projects/pyformex/
##  Copyright 2004-2019 (C) Benedict Verhegghe (benedict.verhegghe@ugent.be)
##  Distributed under the GNU General Public License version 3 or later.
##
##  This program is free software: you can redistribute it and/or modify
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##  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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##
"""A generic interface to the Coords transformation methods

This module defines a generic Geometry superclass which adds all the
possibilities of coordinate transformations offered by the
Coords class to the derived classes.
"""
from __future__ import absolute_import, division, print_function

import numpy as np

import pyformex as pf

from abc import ABCMeta, abstractmethod
if pf.PY2:
     abstractbaseclass = object
if pf.PY3:
     from abc import ABC
     abstractbaseclass = ABC

from pyformex import utils
from pyformex.coords import Coords, Int
from pyformex.attributes import Attributes
from collections import OrderedDict
from pyformex.olist import List
import pyformex.arraytools as at


[docs]class Geometry(abstractbaseclass): """A generic geometry class allowing manipulation of large coordinate sets. The Geometry class is a generic parent class for all geometry classes. It is not intended to be used directly, but only through derived classes. Examples of derived classes are :class:`~formex.Formex`, :class:`~mesh.Mesh` and its subclass :class:`~trisurface.TriSurface`, :class:`~plugins.curve.Curve`. The basic entity of geometry is the point, defined by its coordinates. The Geometry class expects these to be stored in a :class:`~coords.Coords` object assigned to the :attr:`coords` attribute (it is the responsability of the derived class object initialisation to do this). The Geometry class exposes the following attributes of the :attr:`coords` attribute, so that they can be directly used on the Geometry object: :attr:`xyz`, :attr:`x`, :attr:`y`, :attr:`z`, :attr:`xy`, :attr:`yz`, :attr:`xz`. The Geometry class exposes a large set of Coords methods for direct used on the derived class objects. These methods are automatically executed on the ``coords`` attribute of the object. One set of such methods are those returning some information about the Coords: :meth:`points`, :meth:`bbox`, :meth:`center`, :meth:`bboxPoint`, :meth:`centroid`, :meth:`sizes`, :meth:`dsize`, :meth:`bsphere`, :meth:`bboxes`, :meth:`inertia`, :meth:`principalCS`, :meth:`principalSizes`, :meth:`distanceFromPlane`, :meth:`distanceFromLine`, :meth:`distanceFromPoint`, :meth:`directionalSize`, :meth:`directionalWidth`, :meth:`directionalExtremes`. Thus, if F is an instance of class :class:`~formex.Formex`, then one can use ``F.center()`` as a convenient shorthand for ``F.coords.center()``. Likewise, most of the transformation methods of the :class:~coords.Coords` class are exported through the Geometry class to the derived classes. When called, they will return a new object identical to the original, except for the coordinates, which are transformed by the specified method. Refer to the correponding :class:`~coords.Coords` method for the precise arguments of these methods: :meth:`scale`, :meth:`adjust`, :meth:`translate`, :meth:`centered`, :meth:`align`, :meth:`rotate`, :meth:`shear`, :meth:`reflect`, :meth:`affine`, :meth:`toCS`, :meth:`fromCS`, :meth:`transformCS`, :meth:`position`, :meth:`cylindrical`, :meth:`hyperCylindrical`, :meth:`toCylindrical`, :meth:`spherical`, :meth:`superSpherical`, :meth:`toSpherical`, :meth:`circulize`, :meth:`bump`, :meth:`flare`, :meth:`map`, :meth:`map1`, :meth:`mapd`, :meth:`copyAxes`, :meth:`swapAxes`, :meth:`rollAxes`, :meth:`projectOnPlane`, :meth:`projectOnSphere`, :meth:`projectOnCylinder`, :meth:`isopar`, :meth:`addNoise`, :meth:`rot`, :meth:`trl`. Geometry is a lot more than points however. Therefore the Geometry and its derived classes can represent higher level entities, such as lines, planes, circles, triangles, cubes,... These entities are often represented by multiple points: a line segment would e.g. need two points, a triangle three. Geometry subclasses can implement collections of many such entities, just like the :class:`~coords.Coords` can hold many points. We call these geometric entities 'elements'. The subclass must at least define a method :meth:`nelems` returning the number of elements in the object, even if there is only one. The Geometry class allows the attribution of a property number per element. This is an integer number that can be used as the subclass or user wants. It could be just the element number, or a key into a database with lots of more element attributes. The Geometry class provides methods to handle these property numbers. The Geometry class provides a separate mechanism to store attributes related to how the geometry should be rendered. For this purpose the class defines an ``attrib`` attribute which is an object of class :class:`~attributes.Attributes`. This attribute is callable to set any key/value pairs in its dict. For example, ``F.attrib(color=yellow)`` will make the object F always be drawn in yellow. The Geometry class provides for adding fields to instances of the derived classes. Fields are numerical data (scalar or vectorial) that are defined over the geometry. For example, if the geometry represents a surface, the gaussian curvature of that surface is a field defined over the surface. Field data are stored in :class:`~field.Field` objects and the Geometry object stores them internally in a dict object with the field name as key. The dict is kept in an attribute ``fields`` that is only created when the first Field is added to the object. Finally, the Geometry class also provides the interface for storing the Geometry object on a file in pyFormex's own 'pgf' format. Note ---- When subclassing the Geometry class, care should be taken to obey some rules in order for all the above to work properly. See `UserGuide`. Attributes ---------- coords: :class:`~coords.Coords` A Coords object that holds the coordinates of the points required to describe the type of geometry. prop: int array Element property numbers. This is a 1-dim int array with length :meth:`nelems`. Each element of the Geometry can thus be assigned an integer value. It is up the the subclass to define if and how its instances are divided into elements, and how to use this element property number. attrib: :class:`~attributes.Attributes` An Attributes object that is primarily used to define persisting drawing attributes (like color) for the Geometry object. fields: OrderedDict A dict with the Fields defined on the object. This atribute only exists when at least one Field has been defined. See :meth:`addField`. """ #_attributes_ = [ 'xyz', 'x', 'y', 'z', 'xy', 'xz', 'yz' ] def __init__(self): """Initialize a Geometry""" self.prop = None self.coords = None self.attrib = Attributes() ########################################################################## # # Set the coords # ########################################################################## if pf.PY2: __metaclass__ = ABCMeta def _set_coords_inplace(self, coords): """Replace the current coords with new ones. """ coords = Coords(coords) if coords.shape == self.coords.shape: self.coords = coords return self else: raise ValueError("Invalid reinitialization of Geometry coords") def _set_coords_copy(self, coords): """Return a copy of the object with new coordinates replacing the old. """ return self.copy()._set_coords_inplace(coords) # The default _set_coords inherited by subclasses _set_coords = _set_coords_copy def _coords_property1(funcname): """Export a property on the .coords attribute of the object. This is NOT a decorator function. It would be good to make it into a decorator though. """ doc ="""Return the ``%s`` property of the ``coords`` attribute of the Geometry object. See :attr:`coords.Coords.%s` for details. """ % (funcname, funcname) return property(lambda s: getattr(s.coords, funcname), doc=doc) def _coords_property3(func): """Call a method on the .coords attribute of the object. This is a decorator function. """ funcname = func.__name__ print(func.__code__.co_firstlineno) @property def newf(self, *args, **kargs): """Call the Coords %s method on the coords attribute""" return getattr(self.coords, funcname) #newf.__name__ = func.__name__ newf.fget.__doc__ ="""NEWDOC""" print(newf.fget.__code__.co_firstlineno) # = func.__code__.co_firstlineno return newf xyz = _coords_property1('xyz') x = _coords_property1('x') y = _coords_property1('y') z = _coords_property1('z') xy = _coords_property1('xy') xz = _coords_property1('xz') yz = _coords_property1('yz') @xyz.setter def xyz(self, value): self.coords.xyz = value @x.setter def x(self, value): self.coords.x = value @y.setter def y(self, value): self.coords.y = value @z.setter def z(self, value): self.coords.z = value @xy.setter def xy(self, value): self.coords.xy = value @yz.setter def yz(self, value): self.coords.yz = value @xz.setter def xz(self, value): self.coords.xz = value ########################################################################## # # Return information about the coords # ##########################################################################
[docs] @abstractmethod def nelems(self): """Return the number of elements in the Geometry. Returns ------- int The number of elements in the Geometry. This is an abstract method that should be reimplemented by the derived class. """ return 0
[docs] def level(self): """Return the dimensionality of the Geometry The level of a :class:`Geometry` is the dimensionality of the geometric object(s) represented: - 0: points - 1: line objects - 2: surface objects - 3: volume objects Returns ------- int The level of the Geometry, or -1 if it is unknown. This should be implemented by the derived class. The Geometry base class always returns -1. """ return -1
[docs] def info(self): """Return a short string representation about the object """ return "Geometry: coords shape = %s; level = %s" % ( self.coords.shape, self.level())
def _coords_method(func): """Call a method on the .coords attribute of the object. This is a decorator function. """ coords_func = getattr(Coords, func.__name__) def newf(self, *args, **kargs): """Call the Coords %s method on the coords attribute""" return coords_func(self.coords, *args, **kargs) newf.__name__ = func.__name__ newf.__doc__ ="""Call :meth:`~coords.Coords.%s` method on the ``coords`` attribute of the Geometry object. See :meth:`coords.Coords.%s` for details. """ % (func.__name__, func.__name__) return newf
[docs] @_coords_method def points(self): pass
[docs] @_coords_method def bbox(self): pass
[docs] @_coords_method def center(self): pass
[docs] @_coords_method def bboxPoint(self, *args, **kargs): pass
[docs] @_coords_method def centroid(self): pass
[docs] @_coords_method def sizes(self): pass
[docs] @_coords_method def dsize(self): pass
[docs] @_coords_method def bsphere(self): pass
[docs] @_coords_method def bboxes(self): pass
[docs] @_coords_method def inertia(self, *args, **kargs): pass
[docs] @_coords_method def principalCS(self, *args, **kargs): pass
[docs] @_coords_method def principalSizes(self): pass
[docs] @_coords_method def distanceFromPlane(self, *args, **kargs): pass
[docs] @_coords_method def distanceFromLine(self, *args, **kargs): pass
[docs] @_coords_method def distanceFromPoint(self, *args, **kargs): pass
[docs] @_coords_method def directionalSize(self, *args, **kargs): pass
[docs] @_coords_method def directionalWidth(self, *args, **kargs): pass
[docs] @_coords_method def directionalExtremes(self, *args, **kargs): pass
[docs] def convexHull(self, dir=None, return_mesh=True): """Return the convex hull of a Geometry. This is the :meth:`~coords.Coords.convexHull` applied to the ``coords`` attribute, but it has ``return_mesh=True`` as default. Returns ------- Mesh The convex hull of the geometry. """ return self.coords.convexHull(dir, return_mesh)
[docs] def testBbox(self, bb, dirs=(0, 1, 2), nodes='any', atol=0.): """Test which part of a Formex or Mesh is inside a given bbox. The Geometry object needs to have a :meth:`test` method, This is the case for the :class:`~formex.Formex` and :class:`~mesh.Mesh` classes. The test can be applied in 1, 2 or 3 viewing directions. Parameters ---------- bb: Coords (2,3) or alike The bounding box to test for. dirs: tuple of ints (0,1,2) The viewing directions in which to check the bbox bounds. nodes: Same as in :meth:`formex.Formex.test` or :meth:`mesh.Mesh.test`. Returns ------- bool array The array flags the elements that are inside the given bounding box. """ test = [self.test(nodes=nodes, dir=i, min=bb[0][i], max=bb[1][i], atol=atol) for i in dirs] return np.stack(test).all(axis=0)
########### Coords transformations ################# def _coords_transform(func): """Perform a transformation on the .coords attribute of the object. This is a decorator function. """ coords_func = getattr(Coords, func.__name__) def newf(self, *args, **kargs): """Apply a transformation to the coords attribute""" return self._set_coords(coords_func(self.coords, *args, **kargs)) newf.__name__ = func.__name__ newf.__doc__ ="""Apply the :class:`~coords.Coords.%s` transformation to the Geometry object. See :meth:`coords.Coords.%s` for details. """ % (func.__name__, func.__name__) return newf
[docs] @_coords_transform def scale(self, *args, **kargs): pass
[docs] def resized(self, size=1., tol=1.e-5): """Return a copy of the Geometry scaled to the given size. size can be a single value or a list of three values for the three coordinate directions. If it is a single value, all directions are scaled to the same size. Directions for which the geometry has a size smaller than tol times the maximum size are not rescaled. """ s = self.sizes() size = Coords(np.resize(size, (3,))) ignore = s<tol*s.max() s[ignore] = size[ignore] return self.scale(size/s)
[docs] @_coords_transform def adjust(self, *args, **kargs): pass
[docs] @_coords_transform def translate(self, *args, **kargs): pass
[docs] @_coords_transform def centered(self, *args, **kargs): pass
[docs] @_coords_transform def align(self, *args, **kargs): pass
[docs] @_coords_transform def rotate(self, *args, **kargs): pass
[docs] @_coords_transform def shear(self, *args, **kargs): pass
[docs] @_coords_transform def reflect(self, *args, **kargs): pass
[docs] @_coords_transform def affine(self, *args, **kargs): pass
[docs] @_coords_transform def toCS(self, *args, **kargs): pass
[docs] @_coords_transform def fromCS(self, *args, **kargs): pass
[docs] @_coords_transform def transformCS(self, *args, **kargs): pass
[docs] @_coords_transform def position(self, *args, **kargs): pass
[docs] @_coords_transform def cylindrical(self, *args, **kargs): pass
[docs] @_coords_transform def hyperCylindrical(self, *args, **kargs): pass
[docs] @_coords_transform def toCylindrical(self, *args, **kargs): pass
[docs] @_coords_transform def spherical(self, *args, **kargs): pass
[docs] @_coords_transform def superSpherical(self, *args, **kargs): pass
[docs] @_coords_transform def toSpherical(self, *args, **kargs): pass
[docs] @_coords_transform def circulize(self, *args, **kargs): pass
[docs] @_coords_transform def bump(self, *args, **kargs): pass
[docs] @_coords_transform def flare(self, *args, **kargs): pass
[docs] @_coords_transform def map(self, *args, **kargs): pass
[docs] @_coords_transform def map1(self, *args, **kargs): pass
[docs] @_coords_transform def mapd(self, *args, **kargs): pass
[docs] @_coords_transform def copyAxes(self, *args, **kargs): pass
[docs] @_coords_transform def swapAxes(self, *args, **kargs): pass
[docs] @_coords_transform def rollAxes(self, *args, **kargs): pass
[docs] @_coords_transform def projectOnPlane(self, *args, **kargs): pass
[docs] @_coords_transform def projectOnSphere(self, *args, **kargs): pass
[docs] @_coords_transform def projectOnCylinder(self, *args, **kargs): pass
[docs] @_coords_transform def isopar(self, *args, **kargs): pass
[docs] @_coords_transform def addNoise(self, *args, **kargs): pass
rot = rotate trl = translate ########################################################################## # # Operations on property numbers # ##########################################################################
[docs] def setProp(self, prop=None): """Create or destroy the property array for the Geometry. A property array is a 1-dim integer array with length equal to the number of elements in the Geometry. Each element thus has its own property number. These numbers can be used for any purpose. In derived classes like :class:`~formex.Formex` and :class`~mesh.Mesh` they play an import role when creating new geometry: new elements inherit the property number of their parent element. Properties are also preserved on pure coordinate transformations. Because elements with different property numbers can be drawn in different colors, the property numbers are also often used to impose color. Parameters ---------- prop: int, int :term:`array_like` or 'range' The property number(s) to assign to the elements. If a single int, all elements get the same property value. If the number of passed values is less than the number of elements, the list will be repeated. If more values are passed than the number of elements, the excess ones are ignored. A special value ``'range'`` may be given to set the property numbers equal to the element number. This is equivalent to passing ``arange(self.nelems())``. A value None (default) removes the properties from the Geometry. Returns ------- The calling object ``self``, with the new properties inserted or with the properties deleted if argument is None. Note ---- This is one of the few operations that change the object in-place. It still returns the object itself, so that this operation can be used in a chain with other operations. See Also -------- toProp: Create a valid set of properties for the object whereProp: Find the elements having some property value """ if prop is None: self.prop = None else: if isinstance(prop, str): if prop == 'range': prop = np.arange(self.nelems()) self.prop = self.toProp(prop) return self
[docs] def toProp(self, prop): """Create a valid set of properties for the object. Parameters ---------- prop: int or int :term: The property values to turn into a valid set for the object. If a single int, all elements get the same property value. If the number of passed values is less than the number of elements, the list will be repeated. If more values are passed than the number of elements, the excess ones are ignored. Returns ------- int array A 1-dim int array that is valid as a property array for the Geometry object. The length of the array will is ``self.nelems()`` and the dtype is :attr:`~arraytools.Int`. See Also -------- setProp: Set the properties for the object whereProp: Find the elements having some property value Note ---- When you set the properties (using :meth:`setProp`) you do not need to call this method to validate the properties. It is implicitely called from :meth:`setProp`. """ prop = at.checkArray1D(prop, kind='i', allow='u') return np.resize(prop, (self.nelems(),)).astype(at.Int)
[docs] def maxProp(self): """Return the highest property value used. Returns ------- int The highest value used in the properties array, or -1 if there are no properties. """ if self.prop is None: return -1 else: return self.prop.max()
[docs] def propSet(self): """Return a list with unique property values in use. Returns ------- int array The unique values in the properties array. If no properties are defined, an empty array is returned. """ if self.prop is None: return np.array([], dtype=at.Int) else: return np.unique(self.prop)
[docs] def whereProp(self, prop): """Find the elements having some property value. Parameters ---------- prop: int or int :term: The property value(s) to be found. Returns ------- int array A 1-dim int array with the indices of all the elements that have the property value ``prop``, or one of the values in ``prop``. If the object has no properties, an empty array is returned. See Also -------- setProp: Set the properties for the object toProp: Create a valid set of properties for the object selectProp: Return a Geometry object with only the matching elements """ if self.prop is not None: prop = np.unique(prop) if prop.size > 0: return np.concatenate([np.where(self.prop==v)[0] for v in prop]) return np.array([], dtype=at.Int)
########################################################################## # # Making copies and selections # ##########################################################################
[docs] def copy(self): """Return a deep copy of the Geometry object. Returns ------- Geometry (or subclass) object An object of the same class as the caller, having all the same data (for :attr:`coords`, :attr:`prop`, :attr:`attrib`, :attr:`fields`, and any other attributes possibly set by the subclass), but not sharing any data with the original object. Note ---- This is seldomly used, because it may cause wildly superfluous copying of data. Only used it if you absolutely require data that are independent of those of the caller. """ from copy import deepcopy return deepcopy(self)
@abstractmethod def _select(self, sel, compact=False): """Low level selection This is an abstract method and has to be reimplemented by the derived classes. """ pass
[docs] @utils.warning("warn_select_changed") def select(self, sel, compact=False): """Select some element(s) from a Geometry. Parameters ---------- sel: index-like The index of element(s) to be selected. This can be anything that can be used as an index in an array: - a single element number - a list, or array, of element numbers - a bool list, or array, of length self.nelems(), where True values flag the elements to be selected compact: bool, optional This option is only useful for subclasses that have a ``compact`` method, such as :class:`mesh.Mesh` and its subclasses. If True, the returned object will be compacted, i.e. unused nodes are removed and the nodes are renumbered from zero. If False (default), the node set and numbers are returned unchanged. Returns ------- Geometry (or subclass) object An object of the same class as the caller, but only containing the selected elements. See Also -------- cselect: Return all but the selected elements. clip: Like select, but with compact=True as default. """ return self._select(sel, compact=compact)
[docs] @utils.warning("warn_select_changed") def cselect(self, sel, compact=False): """Return the Geometry with the selected elements removed. Parameters ---------- sel: index-like The index of element(s) to be selected. This can be anything that can be used as an index in an array: - a single element number - a list, or array, of element numbers - a bool list, or array, of length self.nelems(), where True values flag the elements to be selected compact: bool, optional This option is only useful for subclasses that have a ``compact`` method, such as :class:`mesh.Mesh` and its subclasses. If True, the returned object will be compacted, i.e. unused nodes are removed and the nodes are renumbered from zero. If False (default), the node set and numbers are returned unchanged. Returns ------- Geometry (or subclass) object An object of the same class as the caller, but containing all but the selected elements. See Also -------- select: Return a Geometry with only the selected elements. cclip: Like cselect, but with compact=True as default. """ return self._select(at.complement(sel, self.nelems()), compact=compact)
[docs] @utils.warning("warn_clip_changed") def clip(self, sel): """Return a Geometry only containing the selected elements. This is equivalent with :meth:`select` but having ``compact=True`` as default. See Also -------- select: Return a Geometry with only the selected elements. cclip: The complement of clip, returning all but the selected elements. """ return self.select(sel, compact=True)
[docs] @utils.warning("warn_clip_changed") def cclip(self, sel): """Return a Geometry with the selected elements removed. This is equivalent with :meth:`select` but having ``compact=True`` as default. See Also -------- cselect: Return a Geometry with only the selected elements. clip: The complement of cclip, returning only the selected elements. """ return self.cselect(sel, compact=True)
[docs] def selectProp(self, prop, compact=False): """Select elements by their property value. Parameters ---------- prop: int or int :term: The property value(s) for which the elements should be selected. Returns ------- Geometry (or subclass) object An object of the same class as the caller, but only containing the elements that have a property value equal to ``prop``, or one of the values in ``prop``. If the input object has no properties, a copy containing all elements is returned. See Also -------- cselectProp: Return all but the elements with property ``prop``. whereProp: Get the numbers of the elements having a specified property. select: Select the elements with the specified indices. """ if self.prop is None: return self.copy() else: return self._select(self.whereProp(prop), compact=compact)
[docs] def cselectProp(self, prop, compact=False): """Return an object without the elements with property `val`. Parameters ---------- prop: int or int :term: The property value(s) of the elements that should be left out. Returns ------- Geometry (or subclass) object An object of the same class as the caller, with all but the elements that have a property value equal to ``prop``, or one of the values in ``prop``. If the input object has no properties, a copy containing all elements is returned. See Also -------- selectProp: Return only the elements with property ``prop``. whereProp: Get the numbers of the elements having a specified property. cselect: Remove elements by their index. """ if self.prop is None: return self.copy() else: return self.cselect(self.whereProp(prop), compact=compact)
[docs] def splitProp(self, prop=None, compact=True): """Partition a Geometry according to the values in prop. Parameters ---------- prop: int :term:`array_like`, optional A 1-dim int array with length ``self.nelems()`` to be used in place of the objects own :attr:`prop` attribute. If None (default), the latter will be used. Returns ------- :class:`~olist.List` of Geometry objects A list of objects of the same class as the caller. Each object in the list contains all the elements having the same value of `prop`. The number of objects in the list is equal to the number of unique values in `prop`. The list is sorted in ascending order of the `prop` value. If `prop` is None and the the object has no `prop` attribute, an empty list is returned. """ if prop is None: prop = self.prop else: prop = self.toProp(prop) if prop is None: split = [] else: split = [self.select(prop==p, compact=compact) for p in np.unique(prop)] return List(split)
########################################################################## # # Operations on fields # ########################################################################## @property def fields(self): """Return the Fields dict of the Geometry. If the Geometry has no Fields, an empty dict is returned. """ if hasattr(self, '_fields'): return self._fields else: return {}
[docs] def addField(self, fldtype, data, fldname): """Add :class:`~field.Field` data to the :class:`Geometry`. Field data are scalar or vectorial data defined over the Geometry. This convenience function creates a :class:`~field.Field` object with the specified data and adds it to the Geometry object's :attr:`fields` dict. Parameters ---------- fldtype: str The field type. See :class:`~field.Field` for details. data: :term: The field data. See :class:`~field.Field` for details. fldname: str The field name. See :class:`~field.Field` for details. This name is also used as key to store the Field in the :attr:`fields` dict. Returns ------- :class:`~field.Field` The constructed and stored Field object. Note ---- Whenever a Geometry object is exported to a PGF file, all Fields stored inside the Geometry object are included in the PGF file. See Also -------- getField: Retrieve a Field by its name. delField: Deleted a Field. convertField: Convert the Field to another Field type. fieldReport: Return a short report of the stored Fields """ from pyformex.field import Field if not hasattr(self, 'fieldtypes') or fldtype not in self.fieldtypes: raise ValueError("Can not add field of type '%s' to a %s" % (fldtype, self.__class__.__name__)) fld = Field(self, fldtype, data, fldname) return self._add_field(fld)
def _add_field(self, field): """Low level function to add a Field""" if not hasattr(self, '_fields'): self._fields = OrderedDict() self._fields[field.fldname] = field return field
[docs] def getField(self, fldname): """Get the data field with the specified name. Parameters ---------- fldname: str The name of the Field to retrieve. Returns ------- :class:`~field.Field` The data field with the specified name, if it exists in the Geometry object's :attr:`fields`. Returns None if no such key exists. """ if fldname in self.fields: return self.fields[fldname]
[docs] def delField(self, fldname): """Delete the Field with the specified name. Parameters ---------- fldname: str The name of the Field to delete from the Geometry object. A nonexisting name is silently ignored. Returns ------- None """ if fldname in self.fields: del self.fields[fldname]
[docs] def convertField(self, fldname, totype, toname): """Convert the data field with the specified name to another type. Parameters ---------- fldname: str The name of the data Field to convert to another type. A nonexisting name is silently ignored. totype: str The field type to convert to. See :class:`~field.Field` for details. toname: str The name of the new (converted) Field (and key to store it). If the same name is specified as the old Field, that one will be overwritten by the new. Otherwise, both will be kept in the Geometry object's :attr:`fields` dict. Returns ------- :class:`~field.Field` The converted and stored data field. Returns None if the original data field does not exist. """ if fldname in self.fields: fld = self.fields[fldname].convert(totype, toname) return self._add_field(fld)
[docs] def fieldReport(self): """Return a short report of the stored fields Returns ------- str A multiline string with the stored Fields' attributes: name, type, dtype and shape. """ return '\n'.join([ "Field '%s', fldtype '%s', dtype %s, shape %s" % \ (f.fldname, f.fldtype, f.data.dtype, f.data.shape) \ for f in self.fields.values()])
########################################################################## # # Export/import to/from PGF files # ##########################################################################
[docs] def write(self, filename, sep=' ', mode='w', **kargs): """Write a Geometry to a PGF file. This writes the Geometry to a pyFormex Geometry File (PGF) with the specified name. It is a convenient shorthand for:: writeGeomFile(filename, self, sep=sep, mode=mode, **kargs) See :func:`~script.writeGeomFile` for details. """ from pyformex.script import writeGeomFile writeGeomFile(filename, self, sep=sep, mode=mode, **kargs)
[docs] @classmethod def read(clas, filename): """Read a Geometry from a PGF file. This reads a single object (the object) from a PGF file and returns it. It is a convenient shorthand for:: next(readGeomFile(filename, 1).values()) See :func:`~script.readGeomFile` for details. """ from pyformex.script import readGeomFile res = readGeomFile(filename, 1) return next(iter(res.values()))
# End