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SF.net SVN: matplotlib:[5864] trunk/matplotlib/lib/matplotlib/quiver.py
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From: <ef...@us...> - 2008-07-25 03:53:22
|
Revision: 5864
http://matplotlib.svn.sourceforge.net/matplotlib/?rev=5864&view=rev
Author: efiring
Date: 2008-07-25 03:53:18 +0000 (Fri, 25 Jul 2008)
Log Message:
-----------
Fix quiver whitespace
Modified Paths:
--------------
trunk/matplotlib/lib/matplotlib/quiver.py
Modified: trunk/matplotlib/lib/matplotlib/quiver.py
===================================================================
--- trunk/matplotlib/lib/matplotlib/quiver.py 2008-07-25 03:41:21 UTC (rev 5863)
+++ trunk/matplotlib/lib/matplotlib/quiver.py 2008-07-25 03:53:18 UTC (rev 5864)
@@ -5,8 +5,8 @@
direction of the vector, with the size of the arrow related to the
magnitude of the vector.
-Barbs are like quiver in that they point along a vector, but
-the magnitude of the vector is given schematically by the presence of barbs
+Barbs are like quiver in that they point along a vector, but
+the magnitude of the vector is given schematically by the presence of barbs
or flags on the barb.
This will also become a home for things such as standard
@@ -23,7 +23,7 @@
import matplotlib.artist as martist
import matplotlib.font_manager as font_manager
from matplotlib.cbook import delete_masked_points
-from matplotlib.patches import CirclePolygon
+from matplotlib.patches import CirclePolygon
import math
@@ -506,63 +506,63 @@
quiver_doc = _quiver_doc
-_barbs_doc = """
-Plot a 2-D field of barbs.
-
-call signatures::
-
- barb(U, V, **kw)
- barb(U, V, C, **kw)
- barb(X, Y, U, V, **kw)
- barb(X, Y, U, V, C, **kw)
-
-Arguments:
-
- *X*, *Y*:
- The x and y coordinates of the barb locations
- (default is head of barb; see *pivot* kwarg)
-
- *U*, *V*:
- give the *x* and *y* components of the barb shaft
-
- *C*:
- an optional array used to map colors to the barbs
-
-All arguments may be 1-D or 2-D arrays or sequences. If *X* and *Y*
-are absent, they will be generated as a uniform grid. If *U* and *V*
-are 2-D arrays but *X* and *Y* are 1-D, and if len(*X*) and len(*Y*)
-match the column and row dimensions of *U*, then *X* and *Y* will be
-expanded with :func:`numpy.meshgrid`.
-
-*U*, *V*, *C* may be masked arrays, but masked *X*, *Y* are not
-supported at present.
-
-Keyword arguments:
-
- *length*:
- Length of the barb in points; the other parts of the barb
- are scaled against this.
- Default is 9
-
- *pivot*: [ 'tip' | 'middle' ]
- The part of the arrow that is at the grid point; the arrow
+_barbs_doc = """
+Plot a 2-D field of barbs.
+
+call signatures::
+
+ barb(U, V, **kw)
+ barb(U, V, C, **kw)
+ barb(X, Y, U, V, **kw)
+ barb(X, Y, U, V, C, **kw)
+
+Arguments:
+
+ *X*, *Y*:
+ The x and y coordinates of the barb locations
+ (default is head of barb; see *pivot* kwarg)
+
+ *U*, *V*:
+ give the *x* and *y* components of the barb shaft
+
+ *C*:
+ an optional array used to map colors to the barbs
+
+All arguments may be 1-D or 2-D arrays or sequences. If *X* and *Y*
+are absent, they will be generated as a uniform grid. If *U* and *V*
+are 2-D arrays but *X* and *Y* are 1-D, and if len(*X*) and len(*Y*)
+match the column and row dimensions of *U*, then *X* and *Y* will be
+expanded with :func:`numpy.meshgrid`.
+
+*U*, *V*, *C* may be masked arrays, but masked *X*, *Y* are not
+supported at present.
+
+Keyword arguments:
+
+ *length*:
+ Length of the barb in points; the other parts of the barb
+ are scaled against this.
+ Default is 9
+
+ *pivot*: [ 'tip' | 'middle' ]
+ The part of the arrow that is at the grid point; the arrow
rotates about this point, hence the name *pivot*.
- Default is 'tip'
-
- *barbcolor*: [ color | color sequence ]
- Specifies the color all parts of the barb except any flags.
- This parameter is analagous to the *edgecolor* parameter
- for polygons, which can be used instead. However this parameter
- will override facecolor.
-
- *flagcolor*: [ color | color sequence ]
- Specifies the color of any flags on the barb.
- This parameter is analagous to the *facecolor* parameter
- for polygons, which can be used instead. However this parameter
- will override facecolor. If this is not set (and *C* has not either)
- then *flagcolor* will be set to match *barbcolor* so that the barb
- has a uniform color. If *C* has been set, *flagcolor* has no effect.
-
+ Default is 'tip'
+
+ *barbcolor*: [ color | color sequence ]
+ Specifies the color all parts of the barb except any flags.
+ This parameter is analagous to the *edgecolor* parameter
+ for polygons, which can be used instead. However this parameter
+ will override facecolor.
+
+ *flagcolor*: [ color | color sequence ]
+ Specifies the color of any flags on the barb.
+ This parameter is analagous to the *facecolor* parameter
+ for polygons, which can be used instead. However this parameter
+ will override facecolor. If this is not set (and *C* has not either)
+ then *flagcolor* will be set to match *barbcolor* so that the barb
+ has a uniform color. If *C* has been set, *flagcolor* has no effect.
+
*sizes*:
A dictionary of coefficients specifying the ratio of a given feature
to the length of the barb. Only those values one wishes to override
@@ -576,7 +576,7 @@
A flag on whether the empty barbs (circles) that are drawn should be filled
with the flag color. If they are not filled, they will be drawn such that
no color is applied to the center.
- Default is False
+ Default is False
*rounding*:
A flag to indicate whether the vector magnitude should be rounded when
@@ -588,7 +588,7 @@
*barb_increments*:
A dictionary of increments specifying values to associate with different
parts of the barb. Only those values one wishes to override need to be
- included.
+ included.
'half' - half barbs (Default is 5)
'full' - full barbs (Default is 10)
'flag' - flags (default is 50)
@@ -602,66 +602,66 @@
wind barbs having these features point towards low pressure in the
Northern Hemisphere.)
Default is False
-
-Barbs are traditionally used in meteorology as a way to plot the speed
-and direction of wind observations, but can technically be used to plot
-any two dimensional vector quantity. As opposed to arrows, which give
-vector magnitude by the length of the arrow, the barbs give more quantitative
-information about the vector magnitude by putting slanted lines or a triangle
-for various increments in magnitude, as show schematically below:
-
- /\ \
- / \ \
- / \ \ \
-/ \ \ \
-------------------------------
-
+
+Barbs are traditionally used in meteorology as a way to plot the speed
+and direction of wind observations, but can technically be used to plot
+any two dimensional vector quantity. As opposed to arrows, which give
+vector magnitude by the length of the arrow, the barbs give more quantitative
+information about the vector magnitude by putting slanted lines or a triangle
+for various increments in magnitude, as show schematically below:
+
+ /\ \
+ / \ \
+ / \ \ \
+/ \ \ \
+------------------------------
+
The largest increment is given by a triangle (or "flag"). After those come full
-lines (barbs). The smallest increment is a half line. There is only, of
-course, ever at most 1 half line. If the magnitude is small and only needs a
-single half-line and no full lines or triangles, the half-line is offset from
-the end of the barb so that it can be easily distinguished from barbs with a
-single full line. The magnitude for the barb shown above would nominally be
-65, using the standard increments of 50, 10, and 5.
-
-linewidths and edgecolors can be used to customize the barb.
-Additional :class:`~matplotlib.collections.PolyCollection`
-keyword arguments:
-
-%(PolyCollection)s
-""" % martist.kwdocd
+lines (barbs). The smallest increment is a half line. There is only, of
+course, ever at most 1 half line. If the magnitude is small and only needs a
+single half-line and no full lines or triangles, the half-line is offset from
+the end of the barb so that it can be easily distinguished from barbs with a
+single full line. The magnitude for the barb shown above would nominally be
+65, using the standard increments of 50, 10, and 5.
-class Barbs(collections.PolyCollection):
- '''
- Specialized PolyCollection for barbs.
-
+linewidths and edgecolors can be used to customize the barb.
+Additional :class:`~matplotlib.collections.PolyCollection`
+keyword arguments:
+
+%(PolyCollection)s
+""" % martist.kwdocd
+
+class Barbs(collections.PolyCollection):
+ '''
+ Specialized PolyCollection for barbs.
+
The only API method is set_UVC(), which can be used
to change the size, orientation, and color of the
arrows. Locations are changed using the set_offsets() collection
method.Possibly this method will be useful in animations.
-
- There is one internal function _find_tails() which finds exactly
- what should be put on the barb given the vector magnitude. From there
- _make_barbs() is used to find the vertices of the polygon to represent the
- barb based on this information.
- '''
- #This may be an abuse of polygons here to render what is essentially maybe
- #1 triangle and a series of lines. It works fine as far as I can tell
- #however.
- def __init__(self, ax, *args, **kw):
- self._pivot = kw.pop('pivot', 'tip')
- self._length = kw.pop('length', 7)
- barbcolor = kw.pop('barbcolor', None)
- flagcolor = kw.pop('flagcolor', None)
+
+ There is one internal function _find_tails() which finds exactly
+ what should be put on the barb given the vector magnitude. From there
+ _make_barbs() is used to find the vertices of the polygon to represent the
+ barb based on this information.
+ '''
+ #This may be an abuse of polygons here to render what is essentially maybe
+ #1 triangle and a series of lines. It works fine as far as I can tell
+ #however.
+ def __init__(self, ax, *args, **kw):
+ self._pivot = kw.pop('pivot', 'tip')
+ self._length = kw.pop('length', 7)
+ barbcolor = kw.pop('barbcolor', None)
+ flagcolor = kw.pop('flagcolor', None)
self.sizes = kw.pop('sizes', dict())
self.fill_empty = kw.pop('fill_empty', False)
self.barb_increments = kw.pop('barb_increments', dict())
self.rounding = kw.pop('rounding', True)
self.flip = kw.pop('flip_barb', False)
- #Flagcolor and and barbcolor provide convenience parameters for setting
- #the facecolor and edgecolor, respectively, of the barb polygon. We
- #also work here to make the flag the same color as the rest of the barb
+ #Flagcolor and and barbcolor provide convenience parameters for setting
+ #the facecolor and edgecolor, respectively, of the barb polygon. We
+ #also work here to make the flag the same color as the rest of the barb
#by default
if None in (barbcolor, flagcolor):
kw['edgecolors'] = 'face'
@@ -671,109 +671,109 @@
kw['facecolors'] = barbcolor
else:
#Set to facecolor passed in or default to black
- kw.setdefault('facecolors', 'k')
+ kw.setdefault('facecolors', 'k')
else:
kw['edgecolors'] = barbcolor
kw['facecolors'] = flagcolor
-
- #Parse out the data arrays from the various configurations supported
+
+ #Parse out the data arrays from the various configurations supported
x, y, u, v, c = self._parse_args(*args)
self.x = x
- self.y = y
- xy = np.hstack((x[:,np.newaxis], y[:,np.newaxis]))
+ self.y = y
+ xy = np.hstack((x[:,np.newaxis], y[:,np.newaxis]))
- #Make a collection
+ #Make a collection
barb_size = self._length**2 / 4 #Empirically determined
collections.PolyCollection.__init__(self, [], (barb_size,), offsets=xy,
- transOffset=ax.transData, **kw)
- self.set_transform(transforms.IdentityTransform())
+ transOffset=ax.transData, **kw)
+ self.set_transform(transforms.IdentityTransform())
self.set_UVC(u, v, c)
-
- __init__.__doc__ = """
- The constructor takes one required argument, an Axes
- instance, followed by the args and kwargs described
- by the following pylab interface documentation:
- %s""" % _barbs_doc
-
- def _find_tails(self, mag, rounding=True, half=5, full=10, flag=50):
+
+ __init__.__doc__ = """
+ The constructor takes one required argument, an Axes
+ instance, followed by the args and kwargs described
+ by the following pylab interface documentation:
+ %s""" % _barbs_doc
+
+ def _find_tails(self, mag, rounding=True, half=5, full=10, flag=50):
'''Find how many of each of the tail pieces is necessary. Flag
specifies the increment for a flag, barb for a full barb, and half for
- half a barb. Mag should be the magnitude of a vector (ie. >= 0).
-
- This returns a tuple of:
- (number of flags, number of barbs, half_flag, empty_flag)
- half_flag is a boolean whether half of a barb is needed, since there
+ half a barb. Mag should be the magnitude of a vector (ie. >= 0).
+
+ This returns a tuple of:
+ (number of flags, number of barbs, half_flag, empty_flag)
+ half_flag is a boolean whether half of a barb is needed, since there
should only ever be one half on a given barb. Empty flag is an array
of flags to easily tell if a barb is empty (too low to plot any
- barbs/flags.'''
+ barbs/flags.'''
#If rounding, round to the nearest multiple of half, the smallest
#increment
if rounding:
mag = half * (mag / half + 0.5).astype(np.int)
-
- num_flags = np.floor(mag / flag).astype(np.int)
- mag = np.mod(mag, flag)
-
- num_barb = np.floor(mag / full).astype(np.int)
- mag = np.mod(mag, full)
-
+
+ num_flags = np.floor(mag / flag).astype(np.int)
+ mag = np.mod(mag, flag)
+
+ num_barb = np.floor(mag / full).astype(np.int)
+ mag = np.mod(mag, full)
+
half_flag = mag >= half
empty_flag = ~(half_flag | (num_flags > 0) | (num_barb > 0))
-
- return num_flags, num_barb, half_flag, empty_flag
-
+
+ return num_flags, num_barb, half_flag, empty_flag
+
def _make_barbs(self, u, v, nflags, nbarbs, half_barb, empty_flag, length,
- pivot, sizes, fill_empty, flip):
+ pivot, sizes, fill_empty, flip):
'''This function actually creates the wind barbs. u and v are
components of the vector in the x and y directions, respectively.
nflags, nbarbs, and half_barb, empty_flag are, respectively, the number
of flags, number of barbs, flag for half a barb, and flag for empty
- barb, ostensibly obtained from _find_tails. length is the length of
- the barb staff in points. pivot specifies the point on the barb around
- which the entire barb should be rotated. Right now valid options are
+ barb, ostensibly obtained from _find_tails. length is the length of
+ the barb staff in points. pivot specifies the point on the barb around
+ which the entire barb should be rotated. Right now valid options are
'head' and 'middle'. sizes is a dictionary of coefficients specifying
the ratio of a given feature to the length of the barb. These features
include:
-
+
spacing - space between features (flags, full/half barbs)
height - height (distance from shaft of top) of a flag or full barb
width - width of a flag, twice the width of a full barb
- emptybarb - radius of the circle used for low magnitudes
-
+ emptybarb - radius of the circle used for low magnitudes
+
fill_empty specifies whether the circle representing an empty barb
should be filled or not (this changes the drawing of the polygon).
flip is a flag indicating whether the features should be flipped to
the other side of the barb (useful for winds in the southern
hemisphere.
-
- This function returns list of arrays of vertices, defining a polygon for
- each of the wind barbs. These polygons have been rotated to properly
+
+ This function returns list of arrays of vertices, defining a polygon for
+ each of the wind barbs. These polygons have been rotated to properly
align with the vector direction.'''
-
- #These control the spacing and size of barb elements relative to the
- #length of the shaft
- spacing = length * sizes.get('spacing', 0.125)
- full_height = length * sizes.get('height', 0.4)
+
+ #These control the spacing and size of barb elements relative to the
+ #length of the shaft
+ spacing = length * sizes.get('spacing', 0.125)
+ full_height = length * sizes.get('height', 0.4)
full_width = length * sizes.get('width', 0.25)
- empty_rad = length * sizes.get('emptybarb', 0.15)
-
- #Controls y point where to pivot the barb.
- pivot_points = dict(tip=0.0, middle=-length/2.)
+ empty_rad = length * sizes.get('emptybarb', 0.15)
+ #Controls y point where to pivot the barb.
+ pivot_points = dict(tip=0.0, middle=-length/2.)
+
#Check for flip
if flip: full_height = -full_height
-
- endx = 0.0
- endy = pivot_points[pivot.lower()]
-
- #Get the appropriate angle for the vector components. The offset is due
- #to the way the barb is initially drawn, going down the y-axis. This
- #makes sense in a meteorological mode of thinking since there 0 degrees
- #corresponds to north (the y-axis traditionally)
- angles = -(ma.arctan2(v, u) + np.pi/2)
-
+
+ endx = 0.0
+ endy = pivot_points[pivot.lower()]
+
+ #Get the appropriate angle for the vector components. The offset is due
+ #to the way the barb is initially drawn, going down the y-axis. This
+ #makes sense in a meteorological mode of thinking since there 0 degrees
+ #corresponds to north (the y-axis traditionally)
+ angles = -(ma.arctan2(v, u) + np.pi/2)
+
#Used for low magnitude. We just get the vertices, so if we make it
#out here, it can be reused. The center set here should put the
#center of the circle at the location(offset), rather than at the
@@ -784,7 +784,7 @@
else:
#If we don't want the empty one filled, we make a degenerate polygon
#that wraps back over itself
- empty_barb = np.concatenate((circ, circ[::-1]))
+ empty_barb = np.concatenate((circ, circ[::-1]))
barb_list = []
for index, angle in np.ndenumerate(angles):
@@ -795,77 +795,77 @@
#orientation
barb_list.append(empty_barb)
continue
-
- poly_verts = [(endx, endy)]
- offset = length
-
- #Add vertices for each flag
- for i in range(nflags[index]):
+
+ poly_verts = [(endx, endy)]
+ offset = length
+
+ #Add vertices for each flag
+ for i in range(nflags[index]):
#The spacing that works for the barbs is a little to much for
- #the flags, but this only occurs when we have more than 1 flag.
- if offset != length: offset += spacing / 2.
- poly_verts.extend([[endx, endy + offset],
- [endx + full_height, endy - full_width/2 + offset],
- [endx, endy - full_width + offset]])
-
- offset -= full_width + spacing
-
+ #the flags, but this only occurs when we have more than 1 flag.
+ if offset != length: offset += spacing / 2.
+ poly_verts.extend([[endx, endy + offset],
+ [endx + full_height, endy - full_width/2 + offset],
+ [endx, endy - full_width + offset]])
+
+ offset -= full_width + spacing
+
#Add vertices for each barb. These really are lines, but works
#great adding 3 vertices that basically pull the polygon out and
- #back down the line
- for i in range(nbarbs[index]):
- poly_verts.extend([(endx, endy + offset),
- (endx + full_height, endy + offset + full_width/2),
- (endx, endy + offset)])
-
- offset -= spacing
-
- #Add the vertices for half a barb, if needed
- if half_barb[index]:
- #If the half barb is the first on the staff, traditionally it is
- #offset from the end to make it easy to distinguish from a barb
- #with a full one
- if offset == length:
- poly_verts.append((endx, endy + offset))
- offset -= 1.5 * spacing
- poly_verts.extend([(endx, endy + offset),
- (endx + full_height/2, endy + offset + full_width/4),
- (endx, endy + offset)])
-
- #Rotate the barb according the angle. Making the barb first and then
- #rotating it made the math for drawing the barb really easy. Also,
- #the transform framework makes doing the rotation simple.
+ #back down the line
+ for i in range(nbarbs[index]):
+ poly_verts.extend([(endx, endy + offset),
+ (endx + full_height, endy + offset + full_width/2),
+ (endx, endy + offset)])
+
+ offset -= spacing
+
+ #Add the vertices for half a barb, if needed
+ if half_barb[index]:
+ #If the half barb is the first on the staff, traditionally it is
+ #offset from the end to make it easy to distinguish from a barb
+ #with a full one
+ if offset == length:
+ poly_verts.append((endx, endy + offset))
+ offset -= 1.5 * spacing
+ poly_verts.extend([(endx, endy + offset),
+ (endx + full_height/2, endy + offset + full_width/4),
+ (endx, endy + offset)])
+
+ #Rotate the barb according the angle. Making the barb first and then
+ #rotating it made the math for drawing the barb really easy. Also,
+ #the transform framework makes doing the rotation simple.
poly_verts = transforms.Affine2D().rotate(-angle).transform(
- poly_verts)
- barb_list.append(poly_verts)
-
- return barb_list
-
- #Taken shamelessly from Quiver
- def _parse_args(self, *args):
- X, Y, U, V, C = [None]*5
- args = list(args)
- if len(args) == 3 or len(args) == 5:
- C = ma.asarray(args.pop(-1)).ravel()
- V = ma.asarray(args.pop(-1))
+ poly_verts)
+ barb_list.append(poly_verts)
+
+ return barb_list
+
+ #Taken shamelessly from Quiver
+ def _parse_args(self, *args):
+ X, Y, U, V, C = [None]*5
+ args = list(args)
+ if len(args) == 3 or len(args) == 5:
+ C = ma.asarray(args.pop(-1)).ravel()
+ V = ma.asarray(args.pop(-1))
U = ma.asarray(args.pop(-1))
- nn = np.shape(U)
- nc = nn[0]
- nr = 1
- if len(nn) > 1:
- nr = nn[1]
- if len(args) == 2: # remaining after removing U,V,C
- X, Y = [np.array(a).ravel() for a in args]
- if len(X) == nc and len(Y) == nr:
- X, Y = [a.ravel() for a in np.meshgrid(X, Y)]
- else:
- indexgrid = np.meshgrid(np.arange(nc), np.arange(nr))
- X, Y = [np.ravel(a) for a in indexgrid]
- return X, Y, U, V, C
+ nn = np.shape(U)
+ nc = nn[0]
+ nr = 1
+ if len(nn) > 1:
+ nr = nn[1]
+ if len(args) == 2: # remaining after removing U,V,C
+ X, Y = [np.array(a).ravel() for a in args]
+ if len(X) == nc and len(Y) == nr:
+ X, Y = [a.ravel() for a in np.meshgrid(X, Y)]
+ else:
+ indexgrid = np.meshgrid(np.arange(nc), np.arange(nr))
+ X, Y = [np.ravel(a) for a in indexgrid]
+ return X, Y, U, V, C
def set_UVC(self, U, V, C=None):
self.u = ma.asarray(U).ravel()
- self.v = ma.asarray(V).ravel()
+ self.v = ma.asarray(V).ravel()
if C is not None:
c = ma.asarray(C).ravel()
x,y,u,v,c = delete_masked_points(self.x.ravel(), self.y.ravel(),
@@ -874,20 +874,20 @@
x,y,u,v = delete_masked_points(self.x.ravel(), self.y.ravel(),
self.u, self.v)
- magnitude = np.sqrt(u*u + v*v)
+ magnitude = np.sqrt(u*u + v*v)
flags, barbs, halves, empty = self._find_tails(magnitude,
- self.rounding, **self.barb_increments)
-
+ self.rounding, **self.barb_increments)
+
#Get the vertices for each of the barbs
-
+
plot_barbs = self._make_barbs(u, v, flags, barbs, halves, empty,
self._length, self._pivot, self.sizes, self.fill_empty, self.flip)
self.set_verts(plot_barbs)
-
+
#Set the color array
if C is not None:
self.set_array(c)
-
+
#Update the offsets in case the masked data changed
xy = np.hstack((x[:,np.newaxis], y[:,np.newaxis]))
self._offsets = xy
@@ -897,7 +897,7 @@
Set the offsets for the barb polygons. This saves the offets passed in
and actually sets version masked as appropriate for the existing U/V
data. *offsets* should be a sequence.
-
+
ACCEPTS: sequence of pairs of floats
'''
self.x = xy[:,0]
@@ -908,5 +908,4 @@
collections.PolyCollection.set_offsets(self, xy)
set_offsets.__doc__ = collections.PolyCollection.set_offsets.__doc__
- barbs_doc = _barbs_doc
-
+ barbs_doc = _barbs_doc
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