Python - Plotting Error Bar Chart with Uneven Errors (High and Low)

user_10602630 0
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I am new on Stack Overflow so apologize if this is a duplicate question or is vague - I am also new at Python and coding in general.

I am wanting to create an error bar graph that has unequal "error limits" on high versus low.

I will be plotting average temperature for a month, with the upper error needing to be the highest temperature of the month and the lower error needing to be the lowest temperature of the month.

I understand how to use an error bar with the errors being equal, but do not understand how to make them unequal.

A picture has been added for reference. A shortened example of the lists I will be using to graph are:

temps_avg = [46, 49, 58, 69, 73, 79, 84]
temps_high = [78, 80, 82, 88, 88, 93, 101]
temps_low = [21, 29, 25, 48, 54, 62, 70]

Bar Chart I'd Like to Duplicate but without Even Error Bars

Bar Chart I'd Like to Duplicate but without Even Error Bars

errorbar matplotlib python
2 Answers

You can place the low and high error limits inside a tuple in the yerr arg of matplotlib's bar plot:

import matplotlib.pyplot as plt
fig, ax = plt.subplots()
ax.bar([0,1,2,3,4,5,6], temps_avg, yerr = (temps_low,temps_high))
user_84478850

Looks to me you can do either of

  1. Draw upper and lower limits separately using lolims, uplims arguments (see here)
  2. Pass the y argument to errorbar so that upper and lower errors are equal, i.e. in your case y = (temps_high+temps_low)/2, this way using temp_avg only to plot line but not the errors.
user_21319570
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