Pandas to MatPlotLib with Dollar Signs - python-3.x

Given the following data frame:
import pandas as pd
df=pd.DataFrame({'A':['$0-$20','$20+']})
df
A
0 0−20
1 $20+
I'd like to create a bar chart in MatPlotLib but I can't seem to get the dollar signs to show up correctly.
Here's what I have:
import matplotlib.pyplot as plt
import numpy as np
y=df.B
x=df.A
ind=np.arange(len(x))
fig, ax = plt.subplots(1, 1, figsize = (2,2))
plt.bar(ind, y, align='center', width=.5, edgecolor='none', color='grey')
ax.patch.set_facecolor('none')
ax.patch.set_alpha(0)
ax.set_ylim([0,5])
ax.set_xlabel(x,fontsize=12,rotation=0,color='grey')
ax.set_xticklabels('')
ax.set_yticklabels('')
I can get the labels to display "better" if I use df.A.values.tolist(), but that just corrects the format.
I'd like each label to display under each bar with the intended original format (with dollar signs).
Thanks in advance!

To specify the xticklabels, pass tick_label=x to plt.bar.
Matplotlib parses labels using a subset of the TeX markup
language. Dollar
signs indicate the beginning (and end) of math mode. So pairs of bare dollar signs are
getting unintentionally swallowed. Currently, there is no a way to disable mathtex parsing. So to prevent the dollar signs from being interpreted as math markup, replace the
bare $ with \$:
df['A'] = df['A'].str.replace('$', '\$')
For example,
import numpy as np
import matplotlib.pyplot as plt
import pandas as pd
df = pd.DataFrame({'A': ['$0-$20', '$20+'], 'B': [10,20]})
df['A'] = df['A'].str.replace('$', '\$')
y = df['B']
x = df['A']
ind = np.arange(len(x))
fig, ax = plt.subplots(1, 1, figsize=(2, 2))
plt.bar(ind, y,
tick_label=x,
align='center', width=.5, edgecolor='none',
color='grey')
plt.show()
Alternatively, you could use df.plot(kind='bar'):
import numpy as np
import matplotlib.pyplot as plt
import pandas as pd
df = pd.DataFrame({'A': ['$0-$20', '$20+'], 'B': [10,20]})
df['A'] = df['A'].str.replace('$', '\$')
fig, ax = plt.subplots(1, 1, figsize=(2, 2))
df.plot(kind='bar', x='A', y='B',
align='center', width=.5, edgecolor='none',
color='grey', ax=ax)
plt.xticks(rotation=25)
plt.show()

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Thank you for your help.

How to add color and legend by points' label one by one in python?

I want to divide and color points,val_lab(611,3) by their labels,pred_LAB(611,)
import numpy as np
import pandas as pd
import matplotlib.pyplot as plt
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#cmap = 'rainbow'
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In your solution you would want to replace c = pred_LAB with c = pred_LAB[i]. But you do not have to use a for loop to plot the data. You can just use the following:
import numpy as np
import pandas as pd
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
# generate random input data
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pred_LAB = np.random.uniform(0,1, (611,))
# plot data
fig = plt.figure()
ax = plt.axes(projection = '3d')
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ax.set_ylabel('A')
ax.set_zlabel('B')
# create one 3D scatter plot - no for loop
ax.scatter3D(
val_lab[:,0],
val_lab[:,1],
val_lab[:,2],
s = 8,
marker='o',
c = pred_LAB,
cmap = 'rainbow',
label='my points'
)
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plt.show()

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Please find the attached figure as well. Your help is much appreciated. :)
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In your example, you could try something like
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