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Making parts of a line graph a different colour depending on their y value in Matplotlib

I'm making a program which takes a random list of data and will plot it.
I want the colour of the graph to change if it goes above a certain value.
https://matplotlib.org/gallery/lines_bars_and_markers/multicolored_line.html
Matplotlib has an entry on doing just this but it seems to require using a function as input for the graph not using lists.
Does anyone know how to either convert this to work for lists or another way of doing so?
Here's my code so far (without my horrific failed attempts to colour code them)
from matplotlib import pyplot as plt
import random
import sys
import numpy as np
#setting the max and min values where I want the colour to change
A_min = 2
B_max = 28
#makes lists for later
A_min_lin = []
B_max_lin = []
#simulating a corruption of the data where it returns all zeros
sim_crpt = random.randint(0,10)
print(sim_crpt)
randomy = []
if sim_crpt == 0:
randomy = []
#making the empty lists for corrupted data
for i in range(0,20):
randomy.append(0)
print(randomy)
else:
#making a random set of values for the y axis
for i in range(0,20):
n = random.randint(0,30)
randomy.append(n)
print(randomy)
#making an x axis for time
time = t = np.arange(0, 20, 1)
#Making a list to plot a straight line showing where the maximum and minimum values
for i in range(0, len(time)):
A_min_lin.append(A_min)
B_max_lin.append(B_max)
#Testing to see if more than 5 y values are zero to return if it's corrupted
tracker = 0
for i in (randomy):
if i == 0:
tracker += 1
if tracker > 5:
sys.exit("Error, no data")
#ploting and showing the different graphs
plt.plot(time,randomy)
plt.plot(time,A_min_lin)
plt.plot(time,B_max_lin)
plt.legend(['Data', 'Minimum for linear', "Maximum for linear"])
plt.show

You can use np.interp to generate the fine-grain data to plot:
# fine grain time
new_time = np.linspace(time.min(), time.max(), 1000)
# interpolate the y values
new_randomy = np.interp(new_time, time, randomy)
# this is copied from the link with few modification
points = np.array([new_time, new_randomy]).T.reshape(-1, 1, 2)
segments = np.concatenate([points[:-1], points[1:]], axis=1)
fig, axs = plt.subplots()
norm = plt.Normalize(new_randomy.min(), new_randomy.max())
lc = LineCollection(segments, cmap='viridis', norm=norm)
# Set the values used for colormapping
lc.set_array(new_randomy[1:])
lc.set_linewidth(2)
line = axs.add_collection(lc)
fig.colorbar(line, ax=axs)
# set the limits
axs.set_xlim(new_time.min(), new_time.max())
axs.set_ylim(new_randomy.min(), new_randomy.max())
plt.show()
Output:

Bar plot animation in Matplotlib (Loop Operation)_New

I would like to animate the data points which i receive from a DL model.
I have followed the answer from here.
I had created my animated plot which satisfies my requirement.
Kindly see the picture below, where it shows X axes labels Defect & No Defect start to raise from 0 and reach a maximum point.
I want two conditions to be met, after the animation completed,
How can I annotate or display a message in the plot after the animation gets completed. (for eg : in my case I want to display maximum value - either defect or No defect in the plot based on the value)
The picture shows below is for 1 iteration which ran for 100 frames. In the same way, i have another 30 iterations data where each of them should run for 100 frames using FuncAnimtaion, which produces animation graph for each iterations and display/annotate the maximum value at the end of iterations.
I can give my 30 iterations one by one and produce results, but how one can achieve in code totally.
Picture
Code
from matplotlib import animation
import matplotlib
from matplotlib import pyplot as plt
import numpy as np
def barlist(n):
# model detail
b = n + 1
c = X_test[0][:b].reshape((-1, b, X_test.shape[2])) # Input to model
mod = model.predict_on_batch(c) # DL Model which takes input c
pred = np.argmax(mod, axis=2) # Output a array
St = np.count_nonzero(pred == 0)
Rt = np.count_nonzero(pred)
return [St, Rt] # for every frame St, Rt gets updated & animate plot
fig = plt.figure()
axes = plt.axes()
axes.set_ylim([0, 110])
x = np.arange(0,2)
my_xticks = ['Defect','No Defect']
plt.xticks(x, my_xticks)
barcollection = plt.bar(x,[0, 0], width= 0.3)
n = 100 #Number of frames
def animate(i):
y = barlist(i)
for i, b in enumerate(barcollection):
b.set_height(y[i])
anim=animation.FuncAnimation(fig,animate,repeat=False,blit=False,frames=n,interval=50)
plt.show()

Adding quantitative values to differentiate data through colours in a scatterplot's legend in Python?

Currently, I'm working on an introductory paper on data manipulation and such; however... the CSV I'm working on has some things I wish to do a scatter graph on!
I want a scatter graph to show me the volume sold on certain items as well as their average price, differentiating all data according to their region (Through colours I assume).
So what I want is to know if I can add the region column as a quantitative value
or if there's a way to make this possible...
It's my first time using Python and I'm confused way too often

I'm not sure if this is what you mean, but here is some working code, assuming you have data in the format of [(country, volume, price), ...]. If not, you can change the inputs to the scatter method as needed.
import random
import pandas as pd
import matplotlib
import matplotlib.pyplot as plt
import numpy as np
n_countries = 50
# get the data into "countries", for example
countries = ...
# in this example: countries is [('BS', 21, 25), ('WZ', 98, 25), ...]
df = pd.DataFrame(countries)
# arbitrary method to get a color
def get_color(i, max_i):
cmap = matplotlib.cm.get_cmap('Spectral')
return cmap(i/max_i)
# get the figure and axis - make a larger figure to fit more points
# add labels for metric names
def get_fig_ax():
fig = plt.figure(figsize=(14,14))
ax = fig.add_subplot(1, 1, 1)
ax.set_xlabel('volume')
ax.set_ylabel('price')
return fig, ax
# switch around the assignments depending on your data
def get_x_y_labels():
x = df[1]
y = df[2]
labels = df[0]
return x, y, labels
offset = 1 # offset just so annotations aren't on top of points
x, y, labels = get_x_y_labels()
fig, ax = get_fig_ax()
# add a point and annotation for each of the labels/regions
for i, region in enumerate(labels):
ax.annotate(region, (x[i] + offset, y[i] + offset))
# note that you must use "label" for "legend" to work
ax.scatter(x[i], y[i], color=get_color(i, len(x)), label=region)
# Add the legend just outside of the plot.
# The .1, 0 at the end will put it outside
ax.legend(loc='upper right', bbox_to_anchor=(1, 1, .1, 0))
plt.show()

Adjusting x-axis in matplotlib

I have a range of values for every hour of year. Which means there are 24 x 365 = 8760 values. I want to plot this information neatly with matplotlib, with x-axis showing January, February......
Here is my current code:
from matplotlib import pyplot as plt
plt.plot(x_data,y_data,label=str("Plot"))
plt.xticks(rotation=45)
plt.xlabel("Time")
plt.ylabel("Y axis values")
plt.title("Y axis values vs Time")
plt.legend(loc='upper right')
axes = plt.gca()
axes.set_ylim([0,some_value * 3])
plt.show()
x_data is a list containing dates in datetime format. y_data contains values corresponding to the values in x_data. How can I get the plot neatly done with months on the X axis? An example:

You could create a scatter plot with horizontal lines as markers. The month is extracted by using the datetime module. In case the dates are not ordered, the plot sorts both lists first according to the date:
#creating a toy dataset for one year, random data points within month-specific limits
from datetime import date, timedelta
import random
x_data = [date(2017, 1, 1) + timedelta(days = i) for i in range(365)]
random.shuffle(x_data)
y_data = [random.randint(50 * (i.month - 1), 50 * i.month) for i in x_data]
#the actual plot starts here
from matplotlib import pyplot as plt
#get a scatter plot with horizontal markers for each data point
#in case the dates are not ordered, sort first the dates and the y values accordingly
plt.scatter([day.strftime("%b") for day in sorted(x_data)], [y for _xsorted, y in sorted(zip(x_data, y_data))], marker = "_", s = 900)
plt.show()
Output
The disadvantage is obviously that the lines have a fixed length. Also, if a month doesn't have a data point, it will not appear in the graph.
Edit 1:
You could also use Axes.hlines, as seen here.
This has the advantage, that the line length changes with the window size. And you don't have to pre-sort the lists, because each start and end point is calculated separately.
The toy dataset is created as above.
from matplotlib import pyplot as plt
#prepare the axis with categories Jan to Dec
x_ax = [date(2017, 1, 1) + timedelta(days = 31 * i) for i in range(12)]
#create invisible bar chart to retrieve start and end points from automatically generated bars
Bars = plt.bar([month.strftime("%b") for month in x_ax], [month.month for month in x_ax], align = "center", alpha = 0)
start_1_12 = [plt.getp(item, "x") for item in Bars]
end_1_12 = [plt.getp(item, "x") + plt.getp(item, "width") for item in Bars]
#retrieve start and end point for each data point line according to its month
x_start = [start_1_12[day.month - 1] for day in x_data]
x_end = [end_1_12[day.month - 1] for day in x_data]
#plot hlines for all data points
plt.hlines(y_data, x_start, x_end, colors = "blue")
plt.show()
Output
Edit 2:
Now your description of the problem is totally different from what you show in your question. You want a simple line plot with specific axis formatting. This can be found easily in the matplotlib documentation and all over SO. An example, how to achieve this with the above created toy dataset would be:
import matplotlib.pyplot as plt
from matplotlib.dates import DateFormatter, MonthLocator
ax = plt.subplot(111)
ax.plot([day for day in sorted(x_data)], [y for _xsorted, y in sorted(zip(x_data, y_data))], "r.-")
ax.xaxis.set_major_locator(MonthLocator(bymonthday=15))
ax.xaxis.set_minor_locator(MonthLocator())
ax.xaxis.set_major_formatter(DateFormatter("%B"))
plt.show()
Output

Generate a heatmap in MatPlotLib using a scatter data set

My question is almost exactly similar to this one. However, I'm not satisfied with the answers, because I want to generate an actual heatmap, without explicitely binning the data.
To be precise, I would like to display the function that is the result of a convolution between the scatter data and a custom kernel, such as 1/x^2.
How should I implement this with matplotlib?
EDIT: Basically, what I have done is this. The result is here. I'd like to keep everything, the axis, the title, the labels and so on. Basically just change the plot to be like I described, while re-implementing as little as possible.

Convert your time series data into a numeric format with matplotlib.dats.date2num. Lay down a rectangular grid that spans your x and y ranges and do your convolution on that plot. Make a pseudo-color plot of your convolution and then reformat the x labels to be dates.
The label formatting is a little messy, but reasonably well documented. You just need to replace AutoDateFormatter with DateFormatter and an appropriate formatting string.
You'll need to tweak the constants in the convolution for your data.
import numpy as np
import datetime as dt
import pylab as plt
import matplotlib.dates as dates
t0 = dt.date.today()
t1 = t0+dt.timedelta(days=10)
times = np.linspace(dates.date2num(t0), dates.date2num(t1), 10)
dt = times[-1]-times[0]
price = 100 - (times-times.mean())**2
dp = price.max() - price.min()
volume = np.linspace(1, 100, 10)
tgrid = np.linspace(times.min(), times.max(), 100)
pgrid = np.linspace(70, 110, 100)
tgrid, pgrid = np.meshgrid(tgrid, pgrid)
heat = np.zeros_like(tgrid)
for t,p,v in zip(times, price, volume):
delt = (t-tgrid)**2
delp = (p-pgrid)**2
heat += v/( delt + delp*1.e-2 + 5.e-1 )**2
fig = plt.figure()
ax = fig.add_subplot(111)
ax.pcolormesh(tgrid, pgrid, heat, cmap='gist_heat_r')
plt.scatter(times, price, volume, marker='x')
locator = dates.DayLocator()
ax.xaxis.set_major_locator(locator)
ax.xaxis.set_major_formatter(dates.AutoDateFormatter(locator))
fig.autofmt_xdate()
plt.show()