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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"

"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

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<title>matplotlib.sankey — Matplotlib 3.0.3 documentation</title>

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<h1>Source code for matplotlib.sankey</h1><div class="highlight"><pre>

"""

Module for creating Sankey diagrams using matplotlib

"""

import logging

from types import SimpleNamespace

import numpy as np

from matplotlib.cbook import iterable

from matplotlib.path import Path

from matplotlib.patches import PathPatch

from matplotlib.transforms import Affine2D

from matplotlib import docstring

from matplotlib import rcParams

_log = logging.getLogger(__name__)

__author__ = "Kevin L. Davies"

__credits__ = ["Yannick Copin"]

__license__ = "BSD"

__version__ = "2011/09/16"

# Angles [deg/90]

RIGHT = 0

UP = 1

# LEFT = 2

DOWN = 3

<div class="viewcode-block" id="Sankey"><a class="viewcode-back" href="../../api/sankey_api.html#matplotlib.sankey.Sankey">[docs]</a>class Sankey(object):

"""

Sankey diagram in matplotlib

Sankey diagrams are a specific type of flow diagram, in which

the width of the arrows is shown proportionally to the flow

quantity. They are typically used to visualize energy or

material or cost transfers between processes.

`Wikipedia (6/1/2011) <https://en.wikipedia.org/wiki/Sankey_diagram>`_

"""

def __init__(self, ax=None, scale=1.0, unit='', format='%G', gap=0.25,

radius=0.1, shoulder=0.03, offset=0.15, head_angle=100,

margin=0.4, tolerance=1e-6, **kwargs):

"""

Create a new Sankey instance.

Optional keyword arguments:

=============== ===================================================

Field Description

=============== ===================================================

*ax* axes onto which the data should be plotted

If *ax* isn't provided, new axes will be created.

*scale* scaling factor for the flows

*scale* sizes the width of the paths in order to

maintain proper layout. The same scale is applied

to all subdiagrams. The value should be chosen

such that the product of the scale and the sum of

the inputs is approximately 1.0 (and the product of

the scale and the sum of the outputs is

approximately -1.0).

*unit* string representing the physical unit associated

with the flow quantities

If *unit* is None, then none of the quantities are

labeled.

*format* a Python number formatting string to be used in

labeling the flow as a quantity (i.e., a number

times a unit, where the unit is given)

*gap* space between paths that break in/break away

to/from the top or bottom

*radius* inner radius of the vertical paths

*shoulder* size of the shoulders of output arrowS

*offset* text offset (from the dip or tip of the arrow)

*head_angle* angle of the arrow heads (and negative of the angle

of the tails) [deg]

*margin* minimum space between Sankey outlines and the edge

of the plot area

*tolerance* acceptable maximum of the magnitude of the sum of

flows

The magnitude of the sum of connected flows cannot

be greater than *tolerance*.

=============== ===================================================

The optional arguments listed above are applied to all subdiagrams so

that there is consistent alignment and formatting.

If :class:`Sankey` is instantiated with any keyword arguments other

than those explicitly listed above (``**kwargs``), they will be passed

to :meth:`add`, which will create the first subdiagram.

In order to draw a complex Sankey diagram, create an instance of

:class:`Sankey` by calling it without any kwargs::

sankey = Sankey()

Then add simple Sankey sub-diagrams::

sankey.add() # 1

sankey.add() # 2

#...

sankey.add() # n

Finally, create the full diagram::

sankey.finish()

Or, instead, simply daisy-chain those calls::

Sankey().add().add... .add().finish()

.. seealso::

:meth:`add`

:meth:`finish`

**Examples:**

.. plot:: gallery/specialty_plots/sankey_basics.py

"""

# Check the arguments.

if gap < 0:

raise ValueError(

"The gap is negative.\nThis isn't allowed because it "

"would cause the paths to overlap.")

if radius > gap:

raise ValueError(

"The inner radius is greater than the path spacing.\n"

"This isn't allowed because it would cause the paths to overlap.")

if head_angle < 0:

raise ValueError(

"The angle is negative.\nThis isn't allowed "

"because it would cause inputs to look like "

"outputs and vice versa.")

if tolerance < 0:

raise ValueError(

"The tolerance is negative.\nIt must be a magnitude.")

# Create axes if necessary.

if ax is None:

import matplotlib.pyplot as plt

fig = plt.figure()

ax = fig.add_subplot(1, 1, 1, xticks=[], yticks=[])

self.diagrams = []

# Store the inputs.

self.ax = ax

self.unit = unit

self.format = format

self.scale = scale

self.gap = gap

self.radius = radius

self.shoulder = shoulder

self.offset = offset

self.margin = margin

self.pitch = np.tan(np.pi * (1 - head_angle / 180.0) / 2.0)

self.tolerance = tolerance

# Initialize the vertices of tight box around the diagram(s).

self.extent = np.array((np.inf, -np.inf, np.inf, -np.inf))

# If there are any kwargs, create the first subdiagram.

if len(kwargs):

self.add(**kwargs)

def _arc(self, quadrant=0, cw=True, radius=1, center=(0, 0)):

"""

Return the codes and vertices for a rotated, scaled, and translated

90 degree arc.

Optional keyword arguments:

=============== ==========================================

Keyword Description

=============== ==========================================

*quadrant* uses 0-based indexing (0, 1, 2, or 3)

*cw* if True, clockwise

*center* (x, y) tuple of the arc's center

=============== ==========================================

"""

# Note: It would be possible to use matplotlib's transforms to rotate,

# scale, and translate the arc, but since the angles are discrete,

# it's just as easy and maybe more efficient to do it here.

ARC_CODES = [Path.LINETO,

Path.CURVE4,

Path.CURVE4]

# Vertices of a cubic Bezier curve approximating a 90 deg arc

# These can be determined by Path.arc(0,90).

ARC_VERTICES = np.array([[1.00000000e+00, 0.00000000e+00],

[1.00000000e+00, 2.65114773e-01],

[8.94571235e-01, 5.19642327e-01],

[7.07106781e-01, 7.07106781e-01],

[5.19642327e-01, 8.94571235e-01],

[2.65114773e-01, 1.00000000e+00],

# Insignificant

# [6.12303177e-17, 1.00000000e+00]])

[0.00000000e+00, 1.00000000e+00]])

if quadrant == 0 or quadrant == 2:

if cw:

vertices = ARC_VERTICES

else:

vertices = ARC_VERTICES[:, ::-1] # Swap x and y.

elif quadrant == 1 or quadrant == 3:

# Negate x.

if cw:

# Swap x and y.

vertices = np.column_stack((-ARC_VERTICES[:, 1],

ARC_VERTICES[:, 0]))

else:

ARC_VERTICES[:, 1]))

if quadrant > 1:

radius = -radius # Rotate 180 deg.

return list(zip(ARC_CODES, radius * vertices +

np.tile(center, (ARC_VERTICES.shape[0], 1))))

def _add_input(self, path, angle, flow, length):

"""

Add an input to a path and return its tip and label locations.

"""

if angle is None:

return [0, 0], [0, 0]

else:

x, y = path[-1][1] # Use the last point as a reference.

dipdepth = (flow / 2) * self.pitch

if angle == RIGHT:

x -= length

dip = [x + dipdepth, y + flow / 2.0]

path.extend([(Path.LINETO, [x, y]),

(Path.LINETO, dip),

(Path.LINETO, [x, y + flow]),

(Path.LINETO, [x + self.gap, y + flow])])

label_location = [dip[0] - self.offset, dip[1]]

else: # Vertical

x -= self.gap

if angle == UP:

sign = 1

else:

sign = -1

dip = [x - flow / 2, y - sign * (length - dipdepth)]

if angle == DOWN:

quadrant = 2

else:

quadrant = 1

# Inner arc isn't needed if inner radius is zero

if self.radius:

path.extend(self._arc(quadrant=quadrant,

cw=angle == UP,

radius=self.radius,

center=(x + self.radius,

y - sign * self.radius)))

else:

(Path.LINETO, dip),

(Path.LINETO, [x - flow, y - sign * length])])

cw=angle == DOWN,

radius=flow + self.radius,

path.append((Path.LINETO, [x - flow, y + sign * flow]))

label_location = [dip[0], dip[1] - sign * self.offset]

return dip, label_location

def _add_output(self, path, angle, flow, length):

"""

Append an output to a path and return its tip and label locations.

.. note:: *flow* is negative for an output.

"""

if angle is None:

else:

tipheight = (self.shoulder - flow / 2) * self.pitch

if angle == RIGHT:

x += length

tip = [x + tipheight, y + flow / 2.0]

(Path.LINETO, tip),

(Path.LINETO, [x, y - self.shoulder + flow]),

(Path.LINETO, [x - self.gap, y + flow])])

label_location = [tip[0] + self.offset, tip[1]]

else: # Vertical

x += self.gap

if angle == UP:

sign = 1

else:

sign = -1

tip = [x - flow / 2.0, y + sign * (length + tipheight)]

if angle == UP:

quadrant = 3

else:

quadrant = 0

# Inner arc isn't needed if inner radius is zero

if self.radius:

cw=angle == UP,

radius=self.radius,

center=(x - self.radius,

y + sign * self.radius)))

else:

(Path.LINETO, [x - self.shoulder,

y + sign * length]),

(Path.LINETO, tip),

(Path.LINETO, [x + self.shoulder - flow,

y + sign * length]),

(Path.LINETO, [x - flow, y + sign * length])])

cw=angle == DOWN,

radius=self.radius - flow,

label_location = [tip[0], tip[1] + sign * self.offset]

return tip, label_location

def _revert(self, path, first_action=Path.LINETO):

"""

A path is not simply revertable by path[::-1] since the code

specifies an action to take from the **previous** point.

"""

reverse_path = []

next_code = first_action

for code, position in path[::-1]:

reverse_path.append((next_code, position))

next_code = code

return reverse_path

# This might be more efficient, but it fails because 'tuple' object

# doesn't support item assignment:

# path[1] = path[1][-1:0:-1]

# path[1][0] = first_action

# path[2] = path[2][::-1]

# return path

<div class="viewcode-block" id="Sankey.add"><a class="viewcode-back" href="../../api/sankey_api.html#matplotlib.sankey.Sankey.add">[docs]</a> @docstring.dedent_interpd

def add(self, patchlabel='', flows=None, orientations=None, labels='',

trunklength=1.0, pathlengths=0.25, prior=None, connect=(0, 0),

rotation=0, **kwargs):

"""

Add a simple Sankey diagram with flows at the same hierarchical level.

Return value is the instance of :class:`Sankey`.

Optional keyword arguments:

=============== ===================================================

Keyword Description

=============== ===================================================

*patchlabel* label to be placed at the center of the diagram

Note: *label* (not *patchlabel*) will be passed to

the patch through ``**kwargs`` and can be used to

create an entry in the legend.

*flows* array of flow values

By convention, inputs are positive and outputs are

negative.

*orientations* list of orientations of the paths

Valid values are 1 (from/to the top), 0 (from/to

the left or right), or -1 (from/to the bottom). If

*orientations* == 0, inputs will break in from the

left and outputs will break away to the right.

*labels* list of specifications of the labels for the flows

Each value may be *None* (no labels), '' (just

label the quantities), or a labeling string. If a

single value is provided, it will be applied to all

flows. If an entry is a non-empty string, then the

quantity for the corresponding flow will be shown

below the string. However, if the *unit* of the

main diagram is None, then quantities are never

shown, regardless of the value of this argument.

*trunklength* length between the bases of the input and output

groups

*pathlengths* list of lengths of the arrows before break-in or

after break-away

If a single value is given, then it will be applied

to the first (inside) paths on the top and bottom,

and the length of all other arrows will be

justified accordingly. The *pathlengths* are not

applied to the horizontal inputs and outputs.

*prior* index of the prior diagram to which this diagram

should be connected

*connect* a (prior, this) tuple indexing the flow of the

prior diagram and the flow of this diagram which

should be connected

If this is the first diagram or *prior* is *None*,

*connect* will be ignored.

*rotation* angle of rotation of the diagram [deg]

*rotation* is ignored if this diagram is connected

to an existing one (using *prior* and *connect*).

The interpretation of the *orientations* argument

will be rotated accordingly (e.g., if *rotation*

== 90, an *orientations* entry of 1 means to/from

the left).

=============== ===================================================

Valid kwargs are :meth:`matplotlib.patches.PathPatch` arguments:

%(Patch)s

As examples, ``fill=False`` and ``label='A legend entry'``.

By default, ``facecolor='#bfd1d4'`` (light blue) and

``linewidth=0.5``.

The indexing parameters (*prior* and *connect*) are zero-based.

The flows are placed along the top of the diagram from the inside out

in order of their index within the *flows* list or array. They are

placed along the sides of the diagram from the top down and along the

bottom from the outside in.

If the sum of the inputs and outputs is nonzero, the discrepancy

will appear as a cubic Bezier curve along the top and bottom edges of

the trunk.

.. seealso::

:meth:`finish`

"""

# Check and preprocess the arguments.

if flows is None:

flows = np.array([1.0, -1.0])

else:

flows = np.array(flows)

n = flows.shape[0] # Number of flows

if rotation is None:

rotation = 0

else:

# In the code below, angles are expressed in deg/90.

rotation /= 90.0

if orientations is None:

orientations = [0, 0]

if len(orientations) != n:

raise ValueError(

"orientations and flows must have the same length.\n"

"orientations has length %d, but flows has length %d."

% (len(orientations), n))

if labels != '' and getattr(labels, '__iter__', False):

# iterable() isn't used because it would give True if labels is a

# string

if len(labels) != n:

raise ValueError(

"If labels is a list, then labels and flows must have the "

"same length.\nlabels has length %d, but flows has length %d."

% (len(labels), n))

else:

labels = [labels] * n

if trunklength < 0:

raise ValueError(

"trunklength is negative.\nThis isn't allowed, because it would "

"cause poor layout.")

if np.abs(np.sum(flows)) > self.tolerance:

_log.info("The sum of the flows is nonzero (%f).\nIs the "

"system not at steady state?", np.sum(flows))

scaled_flows = self.scale * flows

gain = sum(max(flow, 0) for flow in scaled_flows)

loss = sum(min(flow, 0) for flow in scaled_flows)

if not (0.5 <= gain <= 2.0):

_log.info(

"The scaled sum of the inputs is %f.\nThis may "

"cause poor layout.\nConsider changing the scale so"

" that the scaled sum is approximately 1.0.", gain)

if not (-2.0 <= loss <= -0.5):

_log.info(

"The scaled sum of the outputs is %f.\nThis may "

"cause poor layout.\nConsider changing the scale so"

" that the scaled sum is approximately 1.0.", gain)

if prior is not None:

if prior < 0:

raise ValueError("The index of the prior diagram is negative.")

if min(connect) < 0:

raise ValueError(

"At least one of the connection indices is negative.")

if prior >= len(self.diagrams):

raise ValueError(

"The index of the prior diagram is %d, but there are "

"only %d other diagrams.\nThe index is zero-based."

% (prior, len(self.diagrams)))

if connect[0] >= len(self.diagrams[prior].flows):

raise ValueError(

"The connection index to the source diagram is %d, but "

"that diagram has only %d flows.\nThe index is zero-based."

% (connect[0], len(self.diagrams[prior].flows)))

if connect[1] >= n:

raise ValueError(

"The connection index to this diagram is %d, but this diagram"

"has only %d flows.\n The index is zero-based."

% (connect[1], n))

if self.diagrams[prior].angles[connect[0]] is None:

raise ValueError(

"The connection cannot be made. Check that the magnitude "

"of flow %d of diagram %d is greater than or equal to the "

"specified tolerance." % (connect[0], prior))

flow_error = (self.diagrams[prior].flows[connect[0]] +

flows[connect[1]])

if abs(flow_error) >= self.tolerance:

raise ValueError(

"The scaled sum of the connected flows is %f, which is not "

"within the tolerance (%f)." % (flow_error, self.tolerance))

# Determine if the flows are inputs.

are_inputs = [None] * n

for i, flow in enumerate(flows):

if flow >= self.tolerance:

are_inputs[i] = True

elif flow <= -self.tolerance:

are_inputs[i] = False

else:

_log.info(

"The magnitude of flow %d (%f) is below the "

"tolerance (%f).\nIt will not be shown, and it "

"cannot be used in a connection."

% (i, flow, self.tolerance))

# Determine the angles of the arrows (before rotation).

angles = [None] * n

for i, (orient, is_input) in enumerate(zip(orientations, are_inputs)):

if orient == 1:

if is_input:

angles[i] = DOWN

elif not is_input:

# Be specific since is_input can be None.

angles[i] = UP

elif orient == 0:

if is_input is not None:

angles[i] = RIGHT

else:

if orient != -1:

raise ValueError(

"The value of orientations[%d] is %d, "

"but it must be [ -1 | 0 | 1 ]." % (i, orient))

if is_input:

angles[i] = UP

elif not is_input:

angles[i] = DOWN

# Justify the lengths of the paths.

if iterable(pathlengths):

if len(pathlengths) != n:

raise ValueError(

"If pathlengths is a list, then pathlengths and flows must "

"have the same length.\npathlengths has length %d, but flows "

"has length %d." % (len(pathlengths), n))

else: # Make pathlengths into a list.

urlength = pathlengths

ullength = pathlengths

lrlength = pathlengths

lllength = pathlengths

d = dict(RIGHT=pathlengths)

pathlengths = [d.get(angle, 0) for angle in angles]

# Determine the lengths of the top-side arrows

# from the middle outwards.

for i, (angle, is_input, flow) in enumerate(zip(angles, are_inputs,

scaled_flows)):

if angle == DOWN and is_input:

pathlengths[i] = ullength

ullength += flow

elif angle == UP and not is_input:

pathlengths[i] = urlength

urlength -= flow # Flow is negative for outputs.

# Determine the lengths of the bottom-side arrows

# from the middle outwards.

for i, (angle, is_input, flow) in enumerate(reversed(list(zip(

angles, are_inputs, scaled_flows)))):

if angle == UP and is_input:

pathlengths[n - i - 1] = lllength

lllength += flow

elif angle == DOWN and not is_input:

lrlength -= flow

# Determine the lengths of the left-side arrows

# from the bottom upwards.

has_left_input = False

for i, (angle, is_input, spec) in enumerate(reversed(list(zip(

angles, are_inputs, zip(scaled_flows, pathlengths))))):

if angle == RIGHT:

if is_input:

if has_left_input:

else:

has_left_input = True

# Determine the lengths of the right-side arrows

# from the top downwards.

has_right_output = False

for i, (angle, is_input, spec) in enumerate(zip(

angles, are_inputs, list(zip(scaled_flows, pathlengths)))):

if angle == RIGHT:

if not is_input:

if has_right_output:

pathlengths[i] = 0

else:

has_right_output = True

# Begin the subpaths, and smooth the transition if the sum of the flows

# is nonzero.

urpath = [(Path.MOVETO, [(self.gap - trunklength / 2.0), # Upper right

gain / 2.0]),

(Path.LINETO, [(self.gap - trunklength / 2.0) / 2.0,

gain / 2.0]),

(Path.CURVE4, [(self.gap - trunklength / 2.0) / 8.0,

gain / 2.0]),

(Path.CURVE4, [(trunklength / 2.0 - self.gap) / 8.0,

-loss / 2.0]),

(Path.LINETO, [(trunklength / 2.0 - self.gap) / 2.0,

-loss / 2.0]),

(Path.LINETO, [(trunklength / 2.0 - self.gap),

-loss / 2.0])]

llpath = [(Path.LINETO, [(trunklength / 2.0 - self.gap), # Lower left

loss / 2.0]),

(Path.LINETO, [(trunklength / 2.0 - self.gap) / 2.0,

loss / 2.0]),

(Path.CURVE4, [(trunklength / 2.0 - self.gap) / 8.0,

loss / 2.0]),

-gain / 2.0]),

-gain / 2.0])]

lrpath = [(Path.LINETO, [(trunklength / 2.0 - self.gap), # Lower right

loss / 2.0])]

ulpath = [(Path.LINETO, [self.gap - trunklength / 2.0, # Upper left

gain / 2.0])]

# Add the subpaths and assign the locations of the tips and labels.

tips = np.zeros((n, 2))

label_locations = np.zeros((n, 2))

# Add the top-side inputs and outputs from the middle outwards.

for i, (angle, is_input, spec) in enumerate(zip(

if angle == DOWN and is_input:

tips[i, :], label_locations[i, :] = self._add_input(

ulpath, angle, *spec)

urpath, angle, *spec)

# Add the bottom-side inputs and outputs from the middle outwards.

for i, (angle, is_input, spec) in enumerate(reversed(list(zip(

if angle == UP and is_input:

tip, label_location = self._add_input(llpath, angle, *spec)

tips[n - i - 1, :] = tip

label_locations[n - i - 1, :] = label_location

tip, label_location = self._add_output(lrpath, angle, *spec)

# Add the left-side inputs from the bottom upwards.

has_left_input = False

for i, (angle, is_input, spec) in enumerate(reversed(list(zip(

if angle == RIGHT and is_input:

if not has_left_input:

# Make sure the lower path extends

# at least as far as the upper one.

if llpath[-1][1][0] > ulpath[-1][1][0]:

llpath.append((Path.LINETO, [ulpath[-1][1][0],

llpath[-1][1][1]]))

has_left_input = True

# Add the right-side outputs from the top downwards.

has_right_output = False

for i, (angle, is_input, spec) in enumerate(zip(

if angle == RIGHT and not is_input:

if not has_right_output:

# Make sure the upper path extends

# at least as far as the lower one.

if urpath[-1][1][0] < lrpath[-1][1][0]:

urpath.append((Path.LINETO, [lrpath[-1][1][0],

urpath[-1][1][1]]))

has_right_output = True

urpath, angle, *spec)

# Trim any hanging vertices.

if not has_left_input:

ulpath.pop()

llpath.pop()

if not has_right_output:

lrpath.pop()

urpath.pop()

# Concatenate the subpaths in the correct order (clockwise from top).

path = (urpath + self._revert(lrpath) + llpath + self._revert(ulpath) +

[(Path.CLOSEPOLY, urpath[0][1])])

# Create a patch with the Sankey outline.

codes, vertices = zip(*path)

vertices = np.array(vertices)

def _get_angle(a, r):

if a is None:

return None

else:

return a + r

if prior is None:

if rotation != 0: # By default, none of this is needed.

angles = [_get_angle(angle, rotation) for angle in angles]

rotate = Affine2D().rotate_deg(rotation * 90).transform_affine

tips = rotate(tips)

label_locations = rotate(label_locations)

vertices = rotate(vertices)

text = self.ax.text(0, 0, s=patchlabel, ha='center', va='center')

else:

rotation = (self.diagrams[prior].angles[connect[0]] -

angles[connect[1]])

tips = rotate(tips)

offset = self.diagrams[prior].tips[connect[0]] - tips[connect[1]]

translate = Affine2D().translate(*offset).transform_affine

tips = translate(tips)

label_locations = translate(rotate(label_locations))

vertices = translate(rotate(vertices))

kwds = dict(s=patchlabel, ha='center', va='center')

if rcParams['_internal.classic_mode']:

fc = kwargs.pop('fc', kwargs.pop('facecolor', '#bfd1d4'))

lw = kwargs.pop('lw', kwargs.pop('linewidth', 0.5))

else:

if fc is None:

fc = next(self.ax._get_patches_for_fill.prop_cycler)['color']

patch = PathPatch(Path(vertices, codes), fc=fc, lw=lw, **kwargs)

self.ax.add_patch(patch)

# Add the path labels.

texts = []

for number, angle, label, location in zip(flows, angles, labels,

label_locations):

if label is None or angle is None:

label = ''

elif self.unit is not None:

quantity = self.format % abs(number) + self.unit

if label != '':

label += "\n"

label += quantity

texts.append(self.ax.text(x=location[0], y=location[1],

s=label,

ha='center', va='center'))

# Text objects are placed even they are empty (as long as the magnitude

# of the corresponding flow is larger than the tolerance) in case the

# user wants to provide labels later.

# Expand the size of the diagram if necessary.

self.extent = (min(np.min(vertices[:, 0]),

np.min(label_locations[:, 0]),

self.extent[0]),

max(np.max(vertices[:, 0]),

np.max(label_locations[:, 0]),

self.extent[1]),

min(np.min(vertices[:, 1]),

self.extent[2]),

self.extent[3]))

# Include both vertices _and_ label locations in the extents; there are

# where either could determine the margins (e.g., arrow shoulders).

# Add this diagram as a subdiagram.

self.diagrams.append(

SimpleNamespace(patch=patch, flows=flows, angles=angles, tips=tips,

text=text, texts=texts))

# Allow a daisy-chained call structure (see docstring for the class).

return self</div>

<div class="viewcode-block" id="Sankey.finish"><a class="viewcode-back" href="../../api/sankey_api.html#matplotlib.sankey.Sankey.finish">[docs]</a> def finish(self):

"""

Adjust the axes and return a list of information about the Sankey

subdiagram(s).

Return value is a list of subdiagrams represented with the following

fields:

=============== ===================================================

Field Description

=============== ===================================================

*patch* Sankey outline (an instance of

:class:`~maplotlib.patches.PathPatch`)

*flows* values of the flows (positive for input, negative

for output)

*angles* list of angles of the arrows [deg/90]

For example, if the diagram has not been rotated,

an input to the top side will have an angle of 3

(DOWN), and an output from the top side will have

an angle of 1 (UP). If a flow has been skipped

(because its magnitude is less than *tolerance*),

then its angle will be *None*.

*tips* array in which each row is an [x, y] pair

indicating the positions of the tips (or "dips") of

the flow paths

If the magnitude of a flow is less the *tolerance*

for the instance of :class:`Sankey`, the flow is

skipped and its tip will be at the center of the

diagram.

*text* :class:`~matplotlib.text.Text` instance for the

label of the diagram

*texts* list of :class:`~matplotlib.text.Text` instances

for the labels of flows

=============== ===================================================

.. seealso::

:meth:`add`

"""

self.ax.axis([self.extent[0] - self.margin,

self.extent[1] + self.margin,

self.extent[2] - self.margin,

self.extent[3] + self.margin])

self.ax.set_aspect('equal', adjustable='datalim')

return self.diagrams</div></div>

</pre></div>

</div>

</div>

Last updated on Feb 28, 2019.

Created using

<a href="http://sphinx-doc.org/">Sphinx</a> 1.8.4.

Doc version v3.0.3-2-gfc177a9cd.

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