Change tick text in matplotlib chart

Question

Assume if I wanted to change the tick label of '2' from Y axis to 'B' I used plt.yticsk(2,'B') but it seem to not work out

Is there any way to modify it? here's the code:

import matplotlib.pyplot as plt 

y = [-1,2,3,4,5,0,1]
x = [3,5,3,9,7,1,4]

colorsValue = []
for value in x:
    if value < 4:
        colorsValue.append('yellow')
    elif value >= 4:
        colorsValue.append('red')
    else:
        colorsValue.append('orange')

plt.barh(y, x, color = colorsValue)

plt.ylabel('Y')
plt.xlabel('X')

plt.yticks(2,'b')

plt.show()

score 2 · Accepted Answer · edited Jan 06 '22 at 13:48

you could find inspiration by checking how making what you expect here: https://www.python-graph-gallery.com/191-custom-axis-on-matplotlib-chart

The result might be as below:

import matplotlib.pyplot as plt

y = [-1,2,3,4,5,0,1]
x = [3,5,3,9,7,1,4]
yticks = ['-1','b','3','4','5','0','1']

colorsValue = []
for value in x:
    if value < 4:
        colorsValue.append('yellow')
    elif value >= 4:
        colorsValue.append('red')
    else:
        colorsValue.append('orange')

plt.barh(y, x, color = colorsValue)

plt.ylabel('Y')
plt.xlabel('X')

plt.yticks(y,yticks)

plt.show()

Is that the result you expected?

thanks for your help with chart displaying @Mr. T – ngenne Jan 06 '22 at 13:52 — ngenne, Jan 06 '22 at 13:52

jgru · Answer 2 · 2022-01-06T16:33:27.270

1

you need to query the locations (so-called ticks) and labels first, then you can modify those and set those to your pyplot-object named plt:

import matplotlib.pyplot as plt 
import matplotlib.text

y = [-1,2,3,4,5,0,1]
x = [3,5,3,9,7,1,4]

colorsValue = []
for value in x:
    if value < 4:
        colorsValue.append('yellow')
    elif value >= 4:
        colorsValue.append('red')
    else:
        colorsValue.append('orange')

plt.barh(y, x, color = colorsValue)

plt.ylabel('Y')
plt.xlabel('X')

ticks, labels = plt.yticks()
for i,t in enumerate(ticks):
    labels[i].set_text(t)
    if t == 2:
        labels[i].set_text('b')
plt.yticks(ticks,labels)

plt.show()

This is the resulting plot:

edited Jan 06 '22 at 16:33

answered Jan 06 '22 at 13:39

jgru

181
5

I thought, that it is only of relevance to change on label. The solution could be easily extended to preserve the other, pre-existing labels. I updated my answer, please check it , @Mr.T – jgru Jan 06 '22 at 16:23
Thanks for helping out with embedding the figure, @Mr.T! – jgru Jan 06 '22 at 16:34

Change tick text in matplotlib chart

2 Answers2