Text wrapping works only for vertical labels in matplotlib
Question:
Consider the following plot, where we plot the same data into panel A with vertical labels and into panel B with horizontal labels using text wrapping.
import matplotlib.pyplot as plt
x = "Very long label"
y = "Even much longer label"
z = "Now this is what I call a really long label"
l = [x, y, z]
d = [3, 1, 4]
fig, (axA, axB) = plt.subplots(1, 2, figsize=(10, 5))
axA.bar(l, d)
font_dictA={"va": "center", "ha": "right", "rotation": 90, "wrap": True}
axA.set_xticklabels(l, fontdict= font_dictA)
axA.set_title("Case A: vertical labels")
axB.bar(l, d)
font_dictB={"va": "top", "ha": "center", "rotation": 0, "wrap": True}
axB.set_xticklabels(l, fontdict= font_dictB)
axB.set_title("Case B: horizontal labels")
plt.subplots_adjust(bottom=0.2)
plt.show()
giving the following output:
I assume that text wrapping does not work for horizontal labels is caused by differences in the bounding box calculation which is determined by taking the axis and border into consideration (vertical labels), but not adjacent label text boxes (horizontal labels). Can we easily set the text box dimensions of the labels for the horizontal labels (think: define their max-width)?
Please note that I only want to wrap the text of labels/legends/text with matplotlib functionality; I do not ask for external libraries like textwrap nor for other solutions like rotating labels.
Answers:
Text wrapping doesn’t wrap text to not overlap, it wraps text when it tries to go outside the figure.
For vertical labels it seems as matplotlib wraps the text to have nice labels but it just prevents the text to go outside the figure. You can verify this when you set a tight layout – no wrapping occurs, just the axes is being shrinked to accommodate for the labels so that there’s no need to wrap them (provided it’s possible).
If you make the horizontal label so long that they would go outside the figure they will be wrapped, but only those that would go outside the figure.
See also this source code comment in Text#_get_wrapped_text()
Return a copy of the text with new lines added, so that the text is
wrapped relative to the parent figure.
You can use this code to rotate your text label.
import matplotlib.pyplot as plt
fig = plt.figure()
axis = fig.add_axes([0,0,1,1])
y = [10,20,30]
x = ["This is a large text","Bigger text label","Data can be big"]
axis.bar(x,y)
axis.tick_params(axis='x', rotation=90) # this line is responsible for text label orientation
plt.show()
Consider the following plot, where we plot the same data into panel A with vertical labels and into panel B with horizontal labels using text wrapping.
import matplotlib.pyplot as plt
x = "Very long label"
y = "Even much longer label"
z = "Now this is what I call a really long label"
l = [x, y, z]
d = [3, 1, 4]
fig, (axA, axB) = plt.subplots(1, 2, figsize=(10, 5))
axA.bar(l, d)
font_dictA={"va": "center", "ha": "right", "rotation": 90, "wrap": True}
axA.set_xticklabels(l, fontdict= font_dictA)
axA.set_title("Case A: vertical labels")
axB.bar(l, d)
font_dictB={"va": "top", "ha": "center", "rotation": 0, "wrap": True}
axB.set_xticklabels(l, fontdict= font_dictB)
axB.set_title("Case B: horizontal labels")
plt.subplots_adjust(bottom=0.2)
plt.show()
giving the following output:
I assume that text wrapping does not work for horizontal labels is caused by differences in the bounding box calculation which is determined by taking the axis and border into consideration (vertical labels), but not adjacent label text boxes (horizontal labels). Can we easily set the text box dimensions of the labels for the horizontal labels (think: define their max-width)?
Please note that I only want to wrap the text of labels/legends/text with matplotlib functionality; I do not ask for external libraries like textwrap nor for other solutions like rotating labels.
Text wrapping doesn’t wrap text to not overlap, it wraps text when it tries to go outside the figure.
For vertical labels it seems as matplotlib wraps the text to have nice labels but it just prevents the text to go outside the figure. You can verify this when you set a tight layout – no wrapping occurs, just the axes is being shrinked to accommodate for the labels so that there’s no need to wrap them (provided it’s possible).
If you make the horizontal label so long that they would go outside the figure they will be wrapped, but only those that would go outside the figure.
See also this source code comment in Text#_get_wrapped_text()
Return a copy of the text with new lines added, so that the text is
wrapped relative to the parent figure.
You can use this code to rotate your text label.
import matplotlib.pyplot as plt
fig = plt.figure()
axis = fig.add_axes([0,0,1,1])
y = [10,20,30]
x = ["This is a large text","Bigger text label","Data can be big"]
axis.bar(x,y)
axis.tick_params(axis='x', rotation=90) # this line is responsible for text label orientation
plt.show()