Related
I am trying to fix how python plots my data.
Say:
x = [0,5,9,10,15]
y = [0,1,2,3,4]
matplotlib.pyplot.plot(x,y)
matplotlib.pyplot.show()
The x axis' ticks are plotted in intervals of 5. Is there a way to make it show intervals of 1?
You could explicitly set where you want to tick marks with plt.xticks:
plt.xticks(np.arange(min(x), max(x)+1, 1.0))
For example,
import numpy as np
import matplotlib.pyplot as plt
x = [0,5,9,10,15]
y = [0,1,2,3,4]
plt.plot(x,y)
plt.xticks(np.arange(min(x), max(x)+1, 1.0))
plt.show()
(np.arange was used rather than Python's range function just in case min(x) and max(x) are floats instead of ints.)
The plt.plot (or ax.plot) function will automatically set default x and y limits. If you wish to keep those limits, and just change the stepsize of the tick marks, then you could use ax.get_xlim() to discover what limits Matplotlib has already set.
start, end = ax.get_xlim()
ax.xaxis.set_ticks(np.arange(start, end, stepsize))
The default tick formatter should do a decent job rounding the tick values to a sensible number of significant digits. However, if you wish to have more control over the format, you can define your own formatter. For example,
ax.xaxis.set_major_formatter(ticker.FormatStrFormatter('%0.1f'))
Here's a runnable example:
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.ticker as ticker
x = [0,5,9,10,15]
y = [0,1,2,3,4]
fig, ax = plt.subplots()
ax.plot(x,y)
start, end = ax.get_xlim()
ax.xaxis.set_ticks(np.arange(start, end, 0.712123))
ax.xaxis.set_major_formatter(ticker.FormatStrFormatter('%0.1f'))
plt.show()
Another approach is to set the axis locator:
import matplotlib.ticker as plticker
loc = plticker.MultipleLocator(base=1.0) # this locator puts ticks at regular intervals
ax.xaxis.set_major_locator(loc)
There are several different types of locator depending upon your needs.
Here is a full example:
import matplotlib.pyplot as plt
import matplotlib.ticker as plticker
x = [0,5,9,10,15]
y = [0,1,2,3,4]
fig, ax = plt.subplots()
ax.plot(x,y)
loc = plticker.MultipleLocator(base=1.0) # this locator puts ticks at regular intervals
ax.xaxis.set_major_locator(loc)
plt.show()
I like this solution (from the Matplotlib Plotting Cookbook):
import matplotlib.pyplot as plt
import matplotlib.ticker as ticker
x = [0,5,9,10,15]
y = [0,1,2,3,4]
tick_spacing = 1
fig, ax = plt.subplots(1,1)
ax.plot(x,y)
ax.xaxis.set_major_locator(ticker.MultipleLocator(tick_spacing))
plt.show()
This solution give you explicit control of the tick spacing via the number given to ticker.MultipleLocater(), allows automatic limit determination, and is easy to read later.
In case anyone is interested in a general one-liner, simply get the current ticks and use it to set the new ticks by sampling every other tick.
ax.set_xticks(ax.get_xticks()[::2])
if you just want to set the spacing a simple one liner with minimal boilerplate:
plt.gca().xaxis.set_major_locator(plt.MultipleLocator(1))
also works easily for minor ticks:
plt.gca().xaxis.set_minor_locator(plt.MultipleLocator(1))
a bit of a mouthfull, but pretty compact
This is a bit hacky, but by far the cleanest/easiest to understand example that I've found to do this. It's from an answer on SO here:
Cleanest way to hide every nth tick label in matplotlib colorbar?
for label in ax.get_xticklabels()[::2]:
label.set_visible(False)
Then you can loop over the labels setting them to visible or not depending on the density you want.
edit: note that sometimes matplotlib sets labels == '', so it might look like a label is not present, when in fact it is and just isn't displaying anything. To make sure you're looping through actual visible labels, you could try:
visible_labels = [lab for lab in ax.get_xticklabels() if lab.get_visible() is True and lab.get_text() != '']
plt.setp(visible_labels[::2], visible=False)
This is an old topic, but I stumble over this every now and then and made this function. It's very convenient:
import matplotlib.pyplot as pp
import numpy as np
def resadjust(ax, xres=None, yres=None):
"""
Send in an axis and I fix the resolution as desired.
"""
if xres:
start, stop = ax.get_xlim()
ticks = np.arange(start, stop + xres, xres)
ax.set_xticks(ticks)
if yres:
start, stop = ax.get_ylim()
ticks = np.arange(start, stop + yres, yres)
ax.set_yticks(ticks)
One caveat of controlling the ticks like this is that one does no longer enjoy the interactive automagic updating of max scale after an added line. Then do
gca().set_ylim(top=new_top) # for example
and run the resadjust function again.
I developed an inelegant solution. Consider that we have the X axis and also a list of labels for each point in X.
Example:
import matplotlib.pyplot as plt
x = [0,1,2,3,4,5]
y = [10,20,15,18,7,19]
xlabels = ['jan','feb','mar','apr','may','jun']
Let's say that I want to show ticks labels only for 'feb' and 'jun'
xlabelsnew = []
for i in xlabels:
if i not in ['feb','jun']:
i = ' '
xlabelsnew.append(i)
else:
xlabelsnew.append(i)
Good, now we have a fake list of labels. First, we plotted the original version.
plt.plot(x,y)
plt.xticks(range(0,len(x)),xlabels,rotation=45)
plt.show()
Now, the modified version.
plt.plot(x,y)
plt.xticks(range(0,len(x)),xlabelsnew,rotation=45)
plt.show()
Pure Python Implementation
Below's a pure python implementation of the desired functionality that handles any numeric series (int or float) with positive, negative, or mixed values and allows for the user to specify the desired step size:
import math
def computeTicks (x, step = 5):
"""
Computes domain with given step encompassing series x
# params
x - Required - A list-like object of integers or floats
step - Optional - Tick frequency
"""
xMax, xMin = math.ceil(max(x)), math.floor(min(x))
dMax, dMin = xMax + abs((xMax % step) - step) + (step if (xMax % step != 0) else 0), xMin - abs((xMin % step))
return range(dMin, dMax, step)
Sample Output
# Negative to Positive
series = [-2, 18, 24, 29, 43]
print(list(computeTicks(series)))
[-5, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45]
# Negative to 0
series = [-30, -14, -10, -9, -3, 0]
print(list(computeTicks(series)))
[-30, -25, -20, -15, -10, -5, 0]
# 0 to Positive
series = [19, 23, 24, 27]
print(list(computeTicks(series)))
[15, 20, 25, 30]
# Floats
series = [1.8, 12.0, 21.2]
print(list(computeTicks(series)))
[0, 5, 10, 15, 20, 25]
# Step – 100
series = [118.3, 293.2, 768.1]
print(list(computeTicks(series, step = 100)))
[100, 200, 300, 400, 500, 600, 700, 800]
Sample Usage
import matplotlib.pyplot as plt
x = [0,5,9,10,15]
y = [0,1,2,3,4]
plt.plot(x,y)
plt.xticks(computeTicks(x))
plt.show()
Notice the x-axis has integer values all evenly spaced by 5, whereas the y-axis has a different interval (the matplotlib default behavior, because the ticks weren't specified).
Generalisable one liner, with only Numpy imported:
ax.set_xticks(np.arange(min(x),max(x),1))
Set in the context of the question:
import numpy as np
import matplotlib.pyplot as plt
fig, ax = plt.subplots()
x = [0,5,9,10,15]
y = [0,1,2,3,4]
ax.plot(x,y)
ax.set_xticks(np.arange(min(x),max(x),1))
plt.show()
How it works:
fig, ax = plt.subplots() gives the ax object which contains the axes.
np.arange(min(x),max(x),1) gives an array of interval 1 from the min of x to the max of x. This is the new x ticks that we want.
ax.set_xticks() changes the ticks on the ax object.
xmarks=[i for i in range(1,length+1,1)]
plt.xticks(xmarks)
This worked for me
if you want ticks between [1,5] (1 and 5 inclusive) then replace
length = 5
Since None of the above solutions worked for my usecase, here I provide a solution using None (pun!) which can be adapted to a wide variety of scenarios.
Here is a sample piece of code that produces cluttered ticks on both X and Y axes.
# Note the super cluttered ticks on both X and Y axis.
# inputs
x = np.arange(1, 101)
y = x * np.log(x)
fig = plt.figure() # create figure
ax = fig.add_subplot(111)
ax.plot(x, y)
ax.set_xticks(x) # set xtick values
ax.set_yticks(y) # set ytick values
plt.show()
Now, we clean up the clutter with a new plot that shows only a sparse set of values on both x and y axes as ticks.
# inputs
x = np.arange(1, 101)
y = x * np.log(x)
fig = plt.figure() # create figure
ax = fig.add_subplot(111)
ax.plot(x, y)
ax.set_xticks(x)
ax.set_yticks(y)
# which values need to be shown?
# here, we show every third value from `x` and `y`
show_every = 3
sparse_xticks = [None] * x.shape[0]
sparse_xticks[::show_every] = x[::show_every]
sparse_yticks = [None] * y.shape[0]
sparse_yticks[::show_every] = y[::show_every]
ax.set_xticklabels(sparse_xticks, fontsize=6) # set sparse xtick values
ax.set_yticklabels(sparse_yticks, fontsize=6) # set sparse ytick values
plt.show()
Depending on the usecase, one can adapt the above code simply by changing show_every and using that for sampling tick values for X or Y or both the axes.
If this stepsize based solution doesn't fit, then one can also populate the values of sparse_xticks or sparse_yticks at irregular intervals, if that is what is desired.
You can loop through labels and show or hide those you want:
for i, label in enumerate(ax.get_xticklabels()):
if i % interval != 0:
label.set_visible(False)
One recurring annoyance for me is trying to lign up matplotlib legends with the axes. To put them in the top right outside of the plot, it's usually recommended to do
plt.legend(bbox_to_anchor=(1.04, 1), loc="upper left")
like
import numpy
import matplotlib.pyplot as plt
x = numpy.linspace(-2, 2, 100)
y = x ** 2
plt.plot(x, y, "-", label="x**2")
plt.legend(bbox_to_anchor=(1.04, 1), loc="upper left")
plt.grid()
# plt.show()
plt.savefig("out.png", transparent=True)
This leaves a gap, though:
Fiddling around with the magic values, e.g., bbox_to_anchor=(1.04, 1.015), does move the legend up and down, but if you finally got it somewhat right after a thousand attempts, it's all messed up after resizing the figure.
Any hints on how to do this better?
You can achieve the desired alignment by using borderaxespad=0 while specifying the legend.
Complete code
import numpy
import matplotlib.pyplot as plt
x = numpy.linspace(-2, 2, 100)
y = x ** 2
plt.plot(x, y, "-", label="x**2")
plt.legend(bbox_to_anchor=(1.04, 1), borderaxespad=0) # <--- Here
plt.grid()
I am trying to fix how python plots my data.
Say:
x = [0,5,9,10,15]
y = [0,1,2,3,4]
matplotlib.pyplot.plot(x,y)
matplotlib.pyplot.show()
The x axis' ticks are plotted in intervals of 5. Is there a way to make it show intervals of 1?
You could explicitly set where you want to tick marks with plt.xticks:
plt.xticks(np.arange(min(x), max(x)+1, 1.0))
For example,
import numpy as np
import matplotlib.pyplot as plt
x = [0,5,9,10,15]
y = [0,1,2,3,4]
plt.plot(x,y)
plt.xticks(np.arange(min(x), max(x)+1, 1.0))
plt.show()
(np.arange was used rather than Python's range function just in case min(x) and max(x) are floats instead of ints.)
The plt.plot (or ax.plot) function will automatically set default x and y limits. If you wish to keep those limits, and just change the stepsize of the tick marks, then you could use ax.get_xlim() to discover what limits Matplotlib has already set.
start, end = ax.get_xlim()
ax.xaxis.set_ticks(np.arange(start, end, stepsize))
The default tick formatter should do a decent job rounding the tick values to a sensible number of significant digits. However, if you wish to have more control over the format, you can define your own formatter. For example,
ax.xaxis.set_major_formatter(ticker.FormatStrFormatter('%0.1f'))
Here's a runnable example:
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.ticker as ticker
x = [0,5,9,10,15]
y = [0,1,2,3,4]
fig, ax = plt.subplots()
ax.plot(x,y)
start, end = ax.get_xlim()
ax.xaxis.set_ticks(np.arange(start, end, 0.712123))
ax.xaxis.set_major_formatter(ticker.FormatStrFormatter('%0.1f'))
plt.show()
Another approach is to set the axis locator:
import matplotlib.ticker as plticker
loc = plticker.MultipleLocator(base=1.0) # this locator puts ticks at regular intervals
ax.xaxis.set_major_locator(loc)
There are several different types of locator depending upon your needs.
Here is a full example:
import matplotlib.pyplot as plt
import matplotlib.ticker as plticker
x = [0,5,9,10,15]
y = [0,1,2,3,4]
fig, ax = plt.subplots()
ax.plot(x,y)
loc = plticker.MultipleLocator(base=1.0) # this locator puts ticks at regular intervals
ax.xaxis.set_major_locator(loc)
plt.show()
I like this solution (from the Matplotlib Plotting Cookbook):
import matplotlib.pyplot as plt
import matplotlib.ticker as ticker
x = [0,5,9,10,15]
y = [0,1,2,3,4]
tick_spacing = 1
fig, ax = plt.subplots(1,1)
ax.plot(x,y)
ax.xaxis.set_major_locator(ticker.MultipleLocator(tick_spacing))
plt.show()
This solution give you explicit control of the tick spacing via the number given to ticker.MultipleLocater(), allows automatic limit determination, and is easy to read later.
In case anyone is interested in a general one-liner, simply get the current ticks and use it to set the new ticks by sampling every other tick.
ax.set_xticks(ax.get_xticks()[::2])
if you just want to set the spacing a simple one liner with minimal boilerplate:
plt.gca().xaxis.set_major_locator(plt.MultipleLocator(1))
also works easily for minor ticks:
plt.gca().xaxis.set_minor_locator(plt.MultipleLocator(1))
a bit of a mouthfull, but pretty compact
This is a bit hacky, but by far the cleanest/easiest to understand example that I've found to do this. It's from an answer on SO here:
Cleanest way to hide every nth tick label in matplotlib colorbar?
for label in ax.get_xticklabels()[::2]:
label.set_visible(False)
Then you can loop over the labels setting them to visible or not depending on the density you want.
edit: note that sometimes matplotlib sets labels == '', so it might look like a label is not present, when in fact it is and just isn't displaying anything. To make sure you're looping through actual visible labels, you could try:
visible_labels = [lab for lab in ax.get_xticklabels() if lab.get_visible() is True and lab.get_text() != '']
plt.setp(visible_labels[::2], visible=False)
This is an old topic, but I stumble over this every now and then and made this function. It's very convenient:
import matplotlib.pyplot as pp
import numpy as np
def resadjust(ax, xres=None, yres=None):
"""
Send in an axis and I fix the resolution as desired.
"""
if xres:
start, stop = ax.get_xlim()
ticks = np.arange(start, stop + xres, xres)
ax.set_xticks(ticks)
if yres:
start, stop = ax.get_ylim()
ticks = np.arange(start, stop + yres, yres)
ax.set_yticks(ticks)
One caveat of controlling the ticks like this is that one does no longer enjoy the interactive automagic updating of max scale after an added line. Then do
gca().set_ylim(top=new_top) # for example
and run the resadjust function again.
I developed an inelegant solution. Consider that we have the X axis and also a list of labels for each point in X.
Example:
import matplotlib.pyplot as plt
x = [0,1,2,3,4,5]
y = [10,20,15,18,7,19]
xlabels = ['jan','feb','mar','apr','may','jun']
Let's say that I want to show ticks labels only for 'feb' and 'jun'
xlabelsnew = []
for i in xlabels:
if i not in ['feb','jun']:
i = ' '
xlabelsnew.append(i)
else:
xlabelsnew.append(i)
Good, now we have a fake list of labels. First, we plotted the original version.
plt.plot(x,y)
plt.xticks(range(0,len(x)),xlabels,rotation=45)
plt.show()
Now, the modified version.
plt.plot(x,y)
plt.xticks(range(0,len(x)),xlabelsnew,rotation=45)
plt.show()
Pure Python Implementation
Below's a pure python implementation of the desired functionality that handles any numeric series (int or float) with positive, negative, or mixed values and allows for the user to specify the desired step size:
import math
def computeTicks (x, step = 5):
"""
Computes domain with given step encompassing series x
# params
x - Required - A list-like object of integers or floats
step - Optional - Tick frequency
"""
xMax, xMin = math.ceil(max(x)), math.floor(min(x))
dMax, dMin = xMax + abs((xMax % step) - step) + (step if (xMax % step != 0) else 0), xMin - abs((xMin % step))
return range(dMin, dMax, step)
Sample Output
# Negative to Positive
series = [-2, 18, 24, 29, 43]
print(list(computeTicks(series)))
[-5, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45]
# Negative to 0
series = [-30, -14, -10, -9, -3, 0]
print(list(computeTicks(series)))
[-30, -25, -20, -15, -10, -5, 0]
# 0 to Positive
series = [19, 23, 24, 27]
print(list(computeTicks(series)))
[15, 20, 25, 30]
# Floats
series = [1.8, 12.0, 21.2]
print(list(computeTicks(series)))
[0, 5, 10, 15, 20, 25]
# Step – 100
series = [118.3, 293.2, 768.1]
print(list(computeTicks(series, step = 100)))
[100, 200, 300, 400, 500, 600, 700, 800]
Sample Usage
import matplotlib.pyplot as plt
x = [0,5,9,10,15]
y = [0,1,2,3,4]
plt.plot(x,y)
plt.xticks(computeTicks(x))
plt.show()
Notice the x-axis has integer values all evenly spaced by 5, whereas the y-axis has a different interval (the matplotlib default behavior, because the ticks weren't specified).
Generalisable one liner, with only Numpy imported:
ax.set_xticks(np.arange(min(x),max(x),1))
Set in the context of the question:
import numpy as np
import matplotlib.pyplot as plt
fig, ax = plt.subplots()
x = [0,5,9,10,15]
y = [0,1,2,3,4]
ax.plot(x,y)
ax.set_xticks(np.arange(min(x),max(x),1))
plt.show()
How it works:
fig, ax = plt.subplots() gives the ax object which contains the axes.
np.arange(min(x),max(x),1) gives an array of interval 1 from the min of x to the max of x. This is the new x ticks that we want.
ax.set_xticks() changes the ticks on the ax object.
xmarks=[i for i in range(1,length+1,1)]
plt.xticks(xmarks)
This worked for me
if you want ticks between [1,5] (1 and 5 inclusive) then replace
length = 5
Since None of the above solutions worked for my usecase, here I provide a solution using None (pun!) which can be adapted to a wide variety of scenarios.
Here is a sample piece of code that produces cluttered ticks on both X and Y axes.
# Note the super cluttered ticks on both X and Y axis.
# inputs
x = np.arange(1, 101)
y = x * np.log(x)
fig = plt.figure() # create figure
ax = fig.add_subplot(111)
ax.plot(x, y)
ax.set_xticks(x) # set xtick values
ax.set_yticks(y) # set ytick values
plt.show()
Now, we clean up the clutter with a new plot that shows only a sparse set of values on both x and y axes as ticks.
# inputs
x = np.arange(1, 101)
y = x * np.log(x)
fig = plt.figure() # create figure
ax = fig.add_subplot(111)
ax.plot(x, y)
ax.set_xticks(x)
ax.set_yticks(y)
# which values need to be shown?
# here, we show every third value from `x` and `y`
show_every = 3
sparse_xticks = [None] * x.shape[0]
sparse_xticks[::show_every] = x[::show_every]
sparse_yticks = [None] * y.shape[0]
sparse_yticks[::show_every] = y[::show_every]
ax.set_xticklabels(sparse_xticks, fontsize=6) # set sparse xtick values
ax.set_yticklabels(sparse_yticks, fontsize=6) # set sparse ytick values
plt.show()
Depending on the usecase, one can adapt the above code simply by changing show_every and using that for sampling tick values for X or Y or both the axes.
If this stepsize based solution doesn't fit, then one can also populate the values of sparse_xticks or sparse_yticks at irregular intervals, if that is what is desired.
You can loop through labels and show or hide those you want:
for i, label in enumerate(ax.get_xticklabels()):
if i % interval != 0:
label.set_visible(False)
I am saving two separate figures, that each should contain 2 plots together.
The problem is that the first figure is ok, but the second one, does not gets overwritten on the new plot but on the previous one, but in the saved figure, I only find one of the plots :
This is the first figure , and I get the first figure correctly :
import scipy.stats as s
import numpy as np
import os
import pandas as pd
import openpyxl as pyx
import matplotlib
matplotlib.rcParams["backend"] = "TkAgg"
#matplotlib.rcParams['backend'] = "Qt4Agg"
#matplotlib.rcParams['backend'] = "nbAgg"
import matplotlib.pyplot as plt
import math
data = [336256, 620316, 958846, 1007830, 1080401]
pdf = array([ 0.00449982, 0.0045293 , 0.00455894, 0.02397463,
0.02395788, 0.02394114])
fig, ax = plt.subplots();
fig = plt.figure(figsize=(40,30))
x = np.linspace(np.min(data), np.max(data), 100);
plt.plot(x, s.exponweib.pdf(x, *s.exponweib.fit(data, 1, 1, loc=0, scale=2)))
plt.hist(data, bins = np.linspace(data[0], data[-1], 100), normed=True, alpha= 1)
text1= ' Weibull'
plt.savefig(text1+ '.png' )
datar =np.asarray(data)
mu, sigma = datar.mean() , datar.std() # mean and standard deviation
normal_std = np.sqrt(np.log(1 + (sigma/mu)**2))
normal_mean = np.log(mu) - normal_std**2 / 2
hs = np.random.lognormal(normal_mean, normal_std, 1000)
print(hs.max()) # some finite number
print(hs.mean()) # about 136519
print(hs.std()) # about 50405
count, bins, ignored = plt.hist(hs, 100, normed=True)
x = np.linspace(min(bins), max(bins), 10000)
pdfT = [];
for el in range (len(x)):
pdfTmp = (math.exp(-(np.log(x[el]) - normal_mean)**2 / (2 * normal_std**2)))
pdfT += [pdfTmp]
pdf = np.asarray(pdfT)
This is the second set :
fig, ax = plt.subplots();
fig = plt.figure(figsize=(40,40))
plt.plot(x, pdf, linewidth=2, color='r')
plt.hist(data, bins = np.linspace(data[0], data[-1], 100), normed=True, alpha= 1)
text= ' Lognormal '
plt.savefig(text+ '.png' )
The first plot saves the histogram together with curve. instead the second one only saves the curve
update 1 : looking at This Question , I found out that clearing the plot history will help the figures don't mixed up , but still my second set of plots, I mean the lognormal do not save together, I only get the curve and not the histogram.
This is happening, because you have set normed = True, which means that area under the histogram is normalized to 1. And since your bins are very wide, this means that the actual height of the histogram bars are very small (in this case so small that they are not visible)
If you use
n, bins, _ = plt.hist(data, bins = np.linspace(data[0], data[-1], 100), normed=True, alpha= 1)
n will contain the y-value of your bins and you can confirm this yourself.
Also have a look at the documentation for plt.hist.
So if you set normed to False, the histogram will be visible.
Edit: number of bins
import numpy as np
import matplotlib.pyplot as plt
rand_data = np.random.uniform(0, 1.0, 100)
fig = plt.figure()
ax_1 = fig.add_subplot(211)
ax_1.hist(rand_data, bins=10)
ax_2 = fig.add_subplot(212)
ax_2.hist(rand_data, bins=100)
plt.show()
will give you two plots similar (since its random) to:
which shows how the number of bins changes the histogram.
A histogram visualises the distribution of your data along one dimension, so not sure what you mean by number of inputs and bins.
How can one plot a 2d density with its marginal densities,
along the lines of
scatterplot-with-marginal-histograms-in-ggplot2
or
2D plot with histograms / marginals,
in matplotlib ?
In outline,
# I have --
A = a 2d numpy array >= 0
xdens ~ A.mean(axis=0)
ydens ~ A.mean(axis=1)
# I want --
pl.imshow( A )
pl.plot( xdens ) narrow, below A
pl.plot( ydens ) narrow, left of A, with the x y axes flipped
Added in 2017: see the lovely example of seaborn.jointplot,
also this on SO. (The question was in 2013, before seaborn.)
You can use sharex and sharey with subplots:
import numpy as np
import matplotlib.pyplot as plt
from matplotlib import gridspec
t = np.linspace(0, 31.3, 100)
f = np.linspace(0, 1000, 1000)
a = np.exp(-np.abs(f-200)/200)[:, None] * np.random.rand(t.size)
flim = (f.min(), f.max())
tlim = (t.min(), t.max())
gs = gridspec.GridSpec(2, 2, width_ratios=[1,3], height_ratios=[3,1])
ax = plt.subplot(gs[0,1])
axl = plt.subplot(gs[0,0], sharey=ax)
axb = plt.subplot(gs[1,1], sharex=ax)
ax.imshow(a, origin='lower', extent=tlim+flim, aspect='auto')
plt.xlim(tlim)
axl.plot(a.mean(1), f)
axb.plot(t, a.mean(0))
Which gives you: