I'm trying to add the curved text to the Gauge plot using matplotlib in python
import os, sys
import matplotlib
import seaborn as sns
from matplotlib import cm
# from matplotlib import pyplot as plt
import matplotlib.pyplot as plt
from matplotlib.ticker import FuncFormatter
from matplotlib.patches import Circle, Wedge, Rectangle
# below some functions to deal with some basic trigonometry that we'll be using
# to draw the wedges (i.e. the sectors of the gauge) and to point the arrow to the right sector
def degree_range(n):
start = np.linspace(0,180,n+1, endpoint=True)[0:-1]
end = np.linspace(0,180,n+1, endpoint=True)[1::]
mid_points = start + ((end-start)/2.)
return np.c_[start, end], mid_points
def rot_text(ang):
rotation = np.degrees(np.radians(ang) * np.pi / np.pi - np.radians(90))
return rotation
def gauge(labels=['LOW','MEDIUM','HIGH','VERY HIGH','EXTREME'],
colors='jet_r',
arrow=1,
title='',
size = (6,3),
fname=False):
N = len(labels)
if arrow > N:
raise Exception("\n\nThe category ({}) is greated than \
the length\nof the labels ({})".format(arrow, N))
"""
if colors is a string, we assume it's a matplotlib colormap
and we discretize in N discrete colors
"""
if isinstance(colors, str):
cmap = cm.get_cmap(colors, N)
cmap = cmap(np.arange(N))
colors = cmap[::-1,:].tolist()
if isinstance(colors, list):
if len(colors) == N:
colors = colors[::-1]
else:
raise Exception("\n\nnumber of colors {} not equal \
to number of categories{}\n".format(len(colors), N))
"""
begins the plotting
"""
fig, ax = plt.subplots(figsize=size, dpi=100) # figsize=(5,5)
ang_range, mid_points = degree_range(N)
labels = labels[::-1]
"""
plots the sectors and the arcs
"""
patches = []
for ang, c in zip(ang_range, colors):
# sectors
patches.append(Wedge((0.,0.), .4, *ang, facecolor='w', lw=2))
# arcs
patches.append(Wedge((0.,0.), .4, *ang, width=0.10, facecolor=c, lw=2, alpha=0.5))
[ax.add_patch(p) for p in patches]
"""
set the labels (e.g. 'LOW','MEDIUM',...)
"""
for mid, lab in zip(mid_points, labels):
ax.text(0.35 * np.cos(np.radians(mid)),
0.35 * np.sin(np.radians(mid)),
lab,
horizontalalignment='center',
verticalalignment='center',
fontsize=8,
fontweight='bold',
rotation = rot_text(mid))
"""
set the bottom banner and the title
"""
r = Rectangle((-0.4,-0.1),0.8,0.1, facecolor='w', lw=2)
ax.add_patch(r)
ax.text(0,
-0.05,
title,
horizontalalignment='center',
verticalalignment='center',
fontsize=14,
fontweight='bold')
"""
plots the arrow now
"""
pos = mid_points[abs(arrow - N)]
ax.arrow(0,
0,
0.225 * np.cos(np.radians(pos)),
0.225 * np.sin(np.radians(pos)),
width=0.04,
head_width=0.09,
head_length=0.1,
fc='k',
ec='k')
ax.add_patch(Circle((0, 0), radius=0.02, facecolor='k'))
ax.add_patch(Circle((0, 0), radius=0.01, facecolor='w', zorder=11))
"""
removes frame and ticks, and makes axis equal and tight
"""
ax.set_frame_on(False)
ax.axes.set_xticks([])
ax.axes.set_yticks([])
ax.axis('equal')
plt.tight_layout()
if fname:
fig.savefig(fname, dpi=200)
gauge(labels=['LOW','MEDIUM','HIGH','VERY HIGH','EXTREME','CRITICAL'], \
colors=["#5F4690","#1D6996","#38A6A5","#0F8554","#73AF48","#EDAD08"], arrow=3, size=(5,3), title='drought severity index')
Here the text is rotated but not following the arc curve
How to annotate curved text in matplotlib figure?
