Notebook

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Version Check¶

Plotly's python API is updated frequesntly. Run pip install plotly --upgrade to update your Plotly version.

In [1]:

import plotly
plotly.__version__

Out[1]:

'2.0.2'

Basic Quiver Plot¶

In [2]:

import plotly.plotly as py
import plotly.figure_factory as ff

import numpy as np

x,y = np.meshgrid(np.arange(0, 2, .2), np.arange(0, 2, .2))
u = np.cos(x)*y
v = np.sin(x)*y

fig = ff.create_quiver(x, y, u, v)
py.iplot(fig, filename='Quiver Plot Example')

Out[2]:

Quiver Plot with Points¶

In [3]:

import plotly.plotly as py
import plotly.figure_factory as ff
import plotly.graph_objs as go

import numpy as np

x,y = np.meshgrid(np.arange(-2, 2, .2),
                  np.arange(-2, 2, .25))
z = x*np.exp(-x**2 - y**2)
v, u = np.gradient(z, .2, .2)

# Create quiver figure
fig = ff.create_quiver(x, y, u, v,
                       scale=.25,
                       arrow_scale=.4,
                       name='quiver',
                       line=dict(width=1))

# Create points
points = go.Scatter(x=[-.7, .75], y=[0,0],
                    mode='markers',
                    marker=dict(size=12),
                    name='points')

# Add points to figure
fig['data'].append(points)

py.iplot(fig, filename='Quiver with Points')

Out[3]:

Reference¶

In [4]:

help(ff.create_quiver)

Help on function create_quiver in module plotly.figure_factory._quiver:

create_quiver(x, y, u, v, scale=0.1, arrow_scale=0.3, angle=0.3490658503988659, **kwargs)
    Returns data for a quiver plot.
    
    :param (list|ndarray) x: x coordinates of the arrow locations
    :param (list|ndarray) y: y coordinates of the arrow locations
    :param (list|ndarray) u: x components of the arrow vectors
    :param (list|ndarray) v: y components of the arrow vectors
    :param (float in [0,1]) scale: scales size of the arrows(ideally to
        avoid overlap). Default = .1
    :param (float in [0,1]) arrow_scale: value multiplied to length of barb
        to get length of arrowhead. Default = .3
    :param (angle in radians) angle: angle of arrowhead. Default = pi/9
    :param kwargs: kwargs passed through plotly.graph_objs.Scatter
        for more information on valid kwargs call
        help(plotly.graph_objs.Scatter)
    
    :rtype (dict): returns a representation of quiver figure.
    
    Example 1: Trivial Quiver
    ```
    import plotly.plotly as py
    from plotly.figure_factory import create_quiver
    
    import math
    
    # 1 Arrow from (0,0) to (1,1)
    fig = create_quiver(x=[0], y=[0], u=[1], v=[1], scale=1)
    
    py.plot(fig, filename='quiver')
    ```
    
    Example 2: Quiver plot using meshgrid
    ```
    import plotly.plotly as py
    from plotly.figure_factory import create_quiver
    
    import numpy as np
    import math
    
    # Add data
    x,y = np.meshgrid(np.arange(0, 2, .2), np.arange(0, 2, .2))
    u = np.cos(x)*y
    v = np.sin(x)*y
    
    #Create quiver
    fig = create_quiver(x, y, u, v)
    
    # Plot
    py.plot(fig, filename='quiver')
    ```
    
    Example 3: Styling the quiver plot
    ```
    import plotly.plotly as py
    from plotly.figure_factory import create_quiver
    import numpy as np
    import math
    
    # Add data
    x, y = np.meshgrid(np.arange(-np.pi, math.pi, .5),
                       np.arange(-math.pi, math.pi, .5))
    u = np.cos(x)*y
    v = np.sin(x)*y
    
    # Create quiver
    fig = create_quiver(x, y, u, v, scale=.2, arrow_scale=.3, angle=math.pi/6,
                        name='Wind Velocity', line=Line(width=1))
    
    # Add title to layout
    fig['layout'].update(title='Quiver Plot')
    
    # Plot
    py.plot(fig, filename='quiver')
    ```

In [5]:

from IPython.display import display, HTML

display(HTML('<link href="//fonts.googleapis.com/css?family=Open+Sans:600,400,300,200|Inconsolata|Ubuntu+Mono:400,700" rel="stylesheet" type="text/css" />'))
display(HTML('<link rel="stylesheet" type="text/css" href="http://help.plot.ly/documentation/all_static/css/ipython-notebook-custom.css">'))

! pip install git+https://github.com/plotly/publisher.git --upgrade
import publisher
publisher.publish(
    'quiver.ipynb', 'python/quiver-plots/', 'Python Quiver Plots | plotly',
    'How to make a quiver plot in Python. A quiver plot displays velocity vectors a arrows. ',
    title = 'Python Quiver Plots | plotly',
    name = 'Quiver Plots',
    has_thumbnail='true', thumbnail='thumbnail/quiver-plot.jpg', 
    language='python', 
    display_as='scientific', order=12,
    ipynb= '~notebook_demo/42')  

/usr/local/lib/python2.7/site-packages/IPython/nbconvert.py:13: ShimWarning:

The `IPython.nbconvert` package has been deprecated. You should import from nbconvert instead.

/usr/local/lib/python2.7/site-packages/publisher/publisher.py:53: UserWarning:

Did you "Save" this notebook before running this command? Remember to save, always save.

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