How do I remove the axis tick marks on seaborn heatmap - matplotlib

I have a seaborn heatmap but i need to remove the axis tick marks that show as dashes. I want the tick labels but just need to remove the dash (-) at each tick on both axes. My current code is:
sns.heatmap(df, annot=True, fmt='.2f', center=0)
I tried despine and that didnt work.

#ImportanceOfBeingEarnest had a nice answer in the comments that I wanted to add as an answer (in case the comment gets deleted).
For a heatmap:
ax = sns.heatmap(df, annot=True, fmt='.2f', center=0)
ax.tick_params(left=False, bottom=False) ## other options are right and top
If this were instead a clustermap (like here How to remove x and y axis labels in a clustermap?), you'd have an extra call:
g = sns.clustermap(...)
g.ax_heatmap.tick_params(left=False, bottom=False)
And for anyone who wanders in here looking for the related task of removing tick labels, see this answer (https://stackoverflow.com/a/26428792/3407933).

ax = sns.heatmap(df, annot=True, fmt='.2f', center=0)
ax.tick_params(axis='both', which='both', length=0)
ax is a matplotlib.axes object. All axes parameters can be changed in this object, and here's an example from the matplotlib tutorial on how to change tick parameters. both selects both x and y axis, and then their length is changed to 0, so that the ticks are not visible anymore.

Related

matplotlib tick label anchor -- right align tick labels (on right side axis) and "clip" the left (west) side of the tick labels to the axis

I would like to use the "west" anchor for my tick labels for a twinx (right-side) axis. Looking at the plot below, for example, I would like the left side of the tick labels to be aligned with the right axis.
I attempted a few things below, to no avail.
import matplotlib.pyplot as plt
X = [1,2,3]
fig, ax = plt.subplots()
ax.plot(X)
ax.set_ylim([1,3])
ax.set_yticks(X)
axR = ax.twinx()
axR.set_ylim(ax.get_ylim())
axR.set_yticks(ax.get_yticks())
axR.set_yticklabels(['-1.00', '2.00', '3.00'], ha='right')
# axR.set_yticklabels(['-1.00', '2.00', '3.00'], ha='right', bbox_to_anchor='W')
# axR.set_yticklabels(['-1.00', '2.00', '3.00'], ha='right', bbox=dict(bbox_to_anchor='W'))
# bbox can have args from: https://matplotlib.org/stable/api/_as_gen/matplotlib.patches.FancyBboxPatch.html#matplotlib.patches.FancyBboxPatch
fig.show()
So I had the same problem and stumbled on this question. I tried quite a bit and I basically decided I would need to find the right side of the labels when they are left aligned on the right side and then right align them from this point.
I tried a few things but don't have a lot of experience, so it's not perfect, but it seems to work by finding the coordinates as a bbox. I converted that back and forth to get it as an array (probably a shorter way that I don't know). I then took the gap of the largest one and added that to the spacing.
A few notes: I'm doing this on a subplot, hence ax2. I've also already moved the axis tick labels to the right side with ax2.yaxis.tick_right()
r = plt.gcf().canvas.get_renderer()
coord = ax2.yaxis.get_tightbbox(r)
ytickcoord = [yticks.get_window_extent() for yticks in ax2.get_yticklabels()]
inv = ax2.transData.inverted()
ytickdata = [inv.transform(a) for a in ytickcoord]
ytickdatadisplay = [ax2.transData.transform(a) for a in ytickdata]
gap = [a[1][0]-a[0][0] for a in ytickdatadisplay]
for tick in ax2.yaxis.get_majorticklabels():
tick.set_horizontalalignment("right")
ax2.yaxis.set_tick_params(pad=max(gap)+1)}
Update: I have recently been sent the solution to a similar problem with left alignment on the left side. From this solution, I believe this can be simplified to:
import matplotlib as mpl
import matplotlib.pyplot as plt
fig = plt.figure(figsize =(5,3))
ax = fig.add_axes([0,0,1,1])
plt.plot([0,100,200])
ax.yaxis.tick_right()
# Draw plot to have current tick label positions
plt.draw()
# Read max width of tick labels
ytickcoord = max([yticks.get_window_extent(renderer = plt.gcf().canvas.get_renderer()).width for yticks in ax.get_yticklabels()])
# Change ticks to right aligned
ax.axes.set_yticklabels(ax.yaxis.get_majorticklabels(),ha = "right")
# Add max width of tick labels
ax.yaxis.set_tick_params(pad=ytickcoord+1)
plt.show()
plt.close("all")

How to change Bar-Chart Figure Size [duplicate]

I can't figure out how to rotate the text on the X Axis. Its a time stamp, so as the number of samples increase, they get closer and closer until they overlap. I'd like to rotate the text 90 degrees so as the samples get closer together, they aren't overlapping.
Below is what I have, it works fine with the exception that I can't figure out how to rotate the X axis text.
import sys
import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt
import datetime
font = {'family' : 'normal',
'weight' : 'bold',
'size' : 8}
matplotlib.rc('font', **font)
values = open('stats.csv', 'r').readlines()
time = [datetime.datetime.fromtimestamp(float(i.split(',')[0].strip())) for i in values[1:]]
delay = [float(i.split(',')[1].strip()) for i in values[1:]]
plt.plot(time, delay)
plt.grid(b='on')
plt.savefig('test.png')
This works for me:
plt.xticks(rotation=90)
Many "correct" answers here but I'll add one more since I think some details are left out of several. The OP asked for 90 degree rotation but I'll change to 45 degrees because when you use an angle that isn't zero or 90, you should change the horizontal alignment as well; otherwise your labels will be off-center and a bit misleading (and I'm guessing many people who come here want to rotate axes to something other than 90).
Easiest / Least Code
Option 1
plt.xticks(rotation=45, ha='right')
As mentioned previously, that may not be desirable if you'd rather take the Object Oriented approach.
Option 2
Another fast way (it's intended for date objects but seems to work on any label; doubt this is recommended though):
fig.autofmt_xdate(rotation=45)
fig you would usually get from:
fig = plt.gcf()
fig = plt.figure()
fig, ax = plt.subplots()
fig = ax.figure
Object-Oriented / Dealing directly with ax
Option 3a
If you have the list of labels:
labels = ['One', 'Two', 'Three']
ax.set_xticks([1, 2, 3])
ax.set_xticklabels(labels, rotation=45, ha='right')
In later versions of Matplotlib (3.5+), you can just use set_xticks alone:
ax.set_xticks([1, 2, 3], labels, rotation=45, ha='right')
Option 3b
If you want to get the list of labels from the current plot:
# Unfortunately you need to draw your figure first to assign the labels,
# otherwise get_xticklabels() will return empty strings.
plt.draw()
ax.set_xticks(ax.get_xticks())
ax.set_xticklabels(ax.get_xticklabels(), rotation=45, ha='right')
As above, in later versions of Matplotlib (3.5+), you can just use set_xticks alone:
ax.set_xticks(ax.get_xticks(), ax.get_xticklabels(), rotation=45, ha='right')
Option 4
Similar to above, but loop through manually instead.
for label in ax.get_xticklabels():
label.set_rotation(45)
label.set_ha('right')
Option 5
We still use pyplot (as plt) here but it's object-oriented because we're changing the property of a specific ax object.
plt.setp(ax.get_xticklabels(), rotation=45, ha='right')
Option 6
This option is simple, but AFAIK you can't set label horizontal align this way so another option might be better if your angle is not 90.
ax.tick_params(axis='x', labelrotation=45)
Edit:
There's discussion of this exact "bug" but a fix hasn't been released (as of 3.4.0):
https://github.com/matplotlib/matplotlib/issues/13774
Easy way
As described here, there is an existing method in the matplotlib.pyplot figure class that automatically rotates dates appropriately for you figure.
You can call it after you plot your data (i.e.ax.plot(dates,ydata) :
fig.autofmt_xdate()
If you need to format the labels further, checkout the above link.
Non-datetime objects
As per languitar's comment, the method I suggested for non-datetime xticks would not update correctly when zooming, etc. If it's not a datetime object used as your x-axis data, you should follow Tommy's answer:
for tick in ax.get_xticklabels():
tick.set_rotation(45)
Try pyplot.setp. I think you could do something like this:
x = range(len(time))
plt.xticks(x, time)
locs, labels = plt.xticks()
plt.setp(labels, rotation=90)
plt.plot(x, delay)
Appart from
plt.xticks(rotation=90)
this is also possible:
plt.xticks(rotation='vertical')
I came up with a similar example. Again, the rotation keyword is.. well, it's key.
from pylab import *
fig = figure()
ax = fig.add_subplot(111)
ax.bar( [0,1,2], [1,3,5] )
ax.set_xticks( [ 0.5, 1.5, 2.5 ] )
ax.set_xticklabels( ['tom','dick','harry'], rotation=45 ) ;
If you want to apply rotation on the axes object, the easiest way is using tick_params. For example.
ax.tick_params(axis='x', labelrotation=90)
Matplotlib documentation reference here.
This is useful when you have an array of axes as returned by plt.subplots, and it is more convenient than using set_xticks because in that case you need to also set the tick labels, and also more convenient that those that iterate over the ticks (for obvious reasons)
If using plt:
plt.xticks(rotation=90)
In case of using pandas or seaborn to plot, assuming ax as axes for the plot:
ax.set_xticklabels(ax.get_xticklabels(), rotation=90)
Another way of doing the above:
for tick in ax.get_xticklabels():
tick.set_rotation(45)
My answer is inspired by cjohnson318's answer, but I didn't want to supply a hardcoded list of labels; I wanted to rotate the existing labels:
for tick in ax.get_xticklabels():
tick.set_rotation(45)
The simplest solution is to use:
plt.xticks(rotation=XX)
but also
# Tweak spacing to prevent clipping of tick-labels
plt.subplots_adjust(bottom=X.XX)
e.g for dates I used rotation=45 and bottom=0.20 but you can do some test for your data
import pylab as pl
pl.xticks(rotation = 90)
To rotate the x-axis label to 90 degrees
for tick in ax.get_xticklabels():
tick.set_rotation(45)
It will depend on what are you plotting.
import matplotlib.pyplot as plt
x=['long_text_for_a_label_a',
'long_text_for_a_label_b',
'long_text_for_a_label_c']
y=[1,2,3]
myplot = plt.plot(x,y)
for item in myplot.axes.get_xticklabels():
item.set_rotation(90)
For pandas and seaborn that give you an Axes object:
df = pd.DataFrame(x,y)
#pandas
myplot = df.plot.bar()
#seaborn
myplotsns =sns.barplot(y='0', x=df.index, data=df)
# you can get xticklabels without .axes cause the object are already a
# isntance of it
for item in myplot.get_xticklabels():
item.set_rotation(90)
If you need to rotate labels you may need change the font size too, you can use font_scale=1.0 to do that.

removing ticklabels python

I am plotting a multipanel figure in python using a pandas dataframe. I have used the shorter version:
df1_5.plot(subplots=True, sharex=True);
which removes xtick labels on all but the bottom figure in a 5 row by 1 column figure format.
However in order to customize the plots, I was more explicit about how I plotted and used the following code:
fig, axes = plt.subplots(nrows=5, ncols=1, figsize=(8, 5))
df11_15['V11'].plot(ax=axes[0], ylim=(0, 7)); axes[0].set_title('V1')
df11_15['V12'].plot(ax=axes[1], ylim=(0, 7)); axes[1].set_title('V12')
df11_15['V13'].plot(ax=axes[2], ylim=(-0.5, 1.0)); axes[2].set_title('V13')
df11_15['V14'].plot(ax=axes[3], ylim=(-0.5,0.5)); axes[3].set_title('V14')
df11_15['V15'].plot(ax=axes[4], ylim=(-0.5, 0.5)); axes[4].set_title('V15')
I would like to remove the xticklabels from the upper four plots. Can you tell me how to do this?
I tried:
axes[3].set_axisticklabels()
but was told there was no attribute error named this.
Try this
for label in ax[3].get_xticklabels():
label.set_visible(False)
For completeness I will also provide example on how this works in a loop
# generate 2x4 matrix of subplots
fig, axs = plt.subplots(nrows=4, ncols=2)
for i,ax in enumerate(fig.axes):
# fill histograms with random numbers
ax.hist(np.random.normal(size = 100), bins=20)
# set the same xlim so that making labels invisible makes sense
ax.set_xlim([-4,4])
# make labels invisible only if "ax" is not in the last row
if not ax.is_last_row():
for label in ax.get_xticklabels():
label.set_visible(False)

Matplotlib Subplots -- Get Rid of Tick Labels Altogether

Is there a way to get rid of tick labels altogether when creating an array of subplots in Matplotlib? I am currently needing to specify each plot based on the row and column of a larger data set to which the plot corresponds. I've attempted to use the ax.set_xticks([]) and the similar y-axis command, to no avail.
I recognize that it's probably an unusual request to want to make a plot with no axis data whatsoever, but that's what I need. And I need it to automatically apply to all of the subplots in the array.
You have the right method. Maybe you are not applying the set_xticks to the correct axes.
An example:
import matplotlib.pyplot as plt
import numpy as np
ncols = 5
nrows = 3
# create the plots
fig = plt.figure()
axes = [ fig.add_subplot(nrows, ncols, r * ncols + c) for r in range(0, nrows) for c in range(0, ncols) ]
# add some data
for ax in axes:
ax.plot(np.random.random(10), np.random.random(10), '.')
# remove the x and y ticks
for ax in axes:
ax.set_xticks([])
ax.set_yticks([])
This gives:
Note that each axis instance is stored in a list (axes) and then they can be easily manipulated. As usual, there are several ways of doing this, this is just an example.
Even more concise than #DrV 's answer, remixing #mwaskom's comment, a complete and total one-liner to get rid of all axes in all subplots:
# do some plotting...
plt.subplot(121),plt.imshow(image1)
plt.subplot(122),plt.imshow(image2)
# ....
# one liner to remove *all axes in all subplots*
plt.setp(plt.gcf().get_axes(), xticks=[], yticks=[]);
Note: this must be called before any calls to plt.show()
The commands are the same for subplots
fig = plt.figure()
ax1 = fig.add_subplot(211)
ax2 = fig.add_subplot(212)
ax1.plot([1,2])
ax1.tick_params(
axis='x', # changes apply to the x-axis
which='both', # both major and minor ticks are affected
bottom='off', # ticks along the bottom edge are off
top='off', # ticks along the top edge are off
labelbottom='off' # labels along the bottom edge are off)
)
plt.draw()
You can get rid of the default subplot x and y ticks with simply running the following codes:
fig, ax = plt.subplots()
ax.xaxis.set_major_locator(plt.NullLocator())
ax.yaxis.set_major_locator(plt.NullLocator())
for i in range(3):
ax = fig.add_subplot(3, 1, i+1)
...
Just by adding the 2 aforementioned lines just after fig, ax = plt.subplots() you can remove the default ticks.
One can remove the xticks or yticks by
ax.get_xaxis().set_visible(False)
ax.get_yaxis().set_visible(False)
If you want to turn off also the spines, so having no axis at all, you can use:
ax.spines['bottom'].set_visible(False)
ax.spines['left'].set_visible(False)
And if you want to turn everything off at once, use:
ax.axis("off")

Reducing the distance between two boxplots

I'm drawing the bloxplot shown below using python and matplotlib. Is there any way I can reduce the distance between the two boxplots on the X axis?
This is the code that I'm using to get the figure above:
import matplotlib.pyplot as plt
from matplotlib import rcParams
rcParams['ytick.direction'] = 'out'
rcParams['xtick.direction'] = 'out'
fig = plt.figure()
xlabels = ["CG", "EG"]
ax = fig.add_subplot(111)
ax.boxplot([values_cg, values_eg])
ax.set_xticks(np.arange(len(xlabels))+1)
ax.set_xticklabels(xlabels, rotation=45, ha='right')
fig.subplots_adjust(bottom=0.3)
ylabels = yticks = np.linspace(0, 20, 5)
ax.set_yticks(yticks)
ax.set_yticklabels(ylabels)
ax.tick_params(axis='x', pad=10)
ax.tick_params(axis='y', pad=10)
plt.savefig(os.path.join(output_dir, "output.pdf"))
And this is an example closer to what I'd like to get visually (although I wouldn't mind if the boxplots were even a bit closer to each other):
You can either change the aspect ratio of plot or use the widths kwarg (doc) as such:
ax.boxplot([values_cg, values_eg], widths=1)
to make the boxes wider.
Try changing the aspect ratio using
ax.set_aspect(1.5) # or some other float
The larger then number, the narrower (and taller) the plot should be:
a circle will be stretched such that the height is num times the width. aspect=1 is the same as aspect=’equal’.
http://matplotlib.org/api/axes_api.html#matplotlib.axes.Axes.set_aspect
When your code writes:
ax.set_xticks(np.arange(len(xlabels))+1)
You're putting the first box plot on 0 and the second one on 1 (event though you change the tick labels afterwards), just like in the second, "wanted" example you gave they are set on 1,2,3.
So i think an alternative solution would be to play with the xticks position and the xlim of the plot.
for example using
ax.set_xlim(-1.5,2.5)
would place them closer.
positions : array-like, optional
Sets the positions of the boxes. The ticks and limits are automatically set to match the positions. Defaults to range(1, N+1) where N is the number of boxes to be drawn.
https://matplotlib.org/3.1.1/api/_as_gen/matplotlib.pyplot.boxplot.html
This should do the job!
As #Stevie mentioned, you can use the positions kwarg (doc) to manually set the x-coordinates of the boxes:
ax.boxplot([values_cg, values_eg], positions=[1, 1.3])