unemployment¶

from math import pi

from bokeh.io import show
from bokeh.models import ColumnDataSource, HoverTool, LinearColorMapper
from bokeh.plotting import figure
from bokeh.sampledata.unemployment1948 import data

data['Year'] = [str(x) for x in data['Year']]

years = list(data['Year'])
months = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]

data = data.set_index('Year')

# this is the colormap from the original NYTimes plot
colors = ["#75968f", "#a5bab7", "#c9d9d3", "#e2e2e2", "#dfccce", "#ddb7b1", "#cc7878", "#933b41", "#550b1d"]
mapper = LinearColorMapper(palette=colors)
# Set up the data for plotting. We will need to have values for every
# pair of year/month names. Map the rate to a color.
month = []
year = []
color = []
rate = []
for y in years:
    for m in months:
        month.append(m)
        year.append(y)
        monthly_rate = data[m][y]
        rate.append(monthly_rate)

source = ColumnDataSource(
    data=dict(month=month, year=year, rate=rate)
)

TOOLS = "hover,save,pan,box_zoom,wheel_zoom"

p = figure(title="US Unemployment (1948 - 2013)",
           x_range=years, y_range=list(reversed(months)),
           x_axis_location="above", plot_width=900, plot_height=400,
           tools=TOOLS)

p.grid.grid_line_color = None
p.axis.axis_line_color = None
p.axis.major_tick_line_color = None
p.axis.major_label_text_font_size = "5pt"
p.axis.major_label_standoff = 0
p.xaxis.major_label_orientation = pi / 3

p.rect(x="year", y="month", width=1, height=1,
       source=source,
       fill_color={'field': 'rate', 'transform': mapper},
       line_color=None)

p.select_one(HoverTool).tooltips = [
    ('date', '@month @year'),
    ('rate', '@rate'),
]

show(p)      # show the plot