40 lines
1.4 KiB
Python
40 lines
1.4 KiB
Python
import matplotlib.pyplot as plt
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import numpy as np
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# Initial population at year 1
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initial_population = 1_000_000
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death_rate = 0.10
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# Start and stop years for the graph
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start_year = 4000
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stop_year = 10000
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interval = 500 # Interval for plotting data points
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# Calculate the population at the start of the start_year
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current_population = initial_population
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for _ in range(start_year // 100): # Dividing by 100 as the death rate is applied every 100 years
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current_population -= death_rate * current_population
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# Now calculate and plot the population from start_year to stop_year
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years = np.arange(start_year, stop_year + 1, interval)
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population_values = []
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for year in years:
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# Apply the death rate for each interval (interval/100 times for each period)
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for _ in range(interval // 100):
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current_population -= death_rate * current_population
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population_values.append(current_population)
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# Create the graph with labels for each data point
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plt.figure(figsize=(8, 6))
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plt.plot(years, population_values, marker='o', linestyle='-', color='b')
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plt.xlabel('Years')
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plt.ylabel('Population')
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plt.title(f'Population Projection from Year {start_year} to {stop_year}')
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# Adding labels to the data points
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for i, txt in enumerate(population_values):
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plt.annotate(f"{int(txt):,}", (years[i], population_values[i]), textcoords="offset points", xytext=(0,10), ha='center')
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plt.grid(True)
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plt.show()
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