I am trying to create an animation of a scatterplot as well as a 2d Histogram. I can get the scatter plot working. I can also create individual stills of the 2d Histogram but cannot get it to animate with the scatter plot.
I can create some mock data if that would help. Please find code below.
import numpy as np
import matplotlib.pyplot as plt
import csv
import matplotlib.animation as animation
#Create empty lists
visuals = [[],[],[]]
#This dataset contains XY coordinates from 21 different players derived from a match
with open('Heatmap_dataset.csv') as csvfile :
readCSV = csv.reader(csvfile, delimiter=',')
n=0
for row in readCSV :
if n == 0 :
n+=1
continue
#All I'm doing here is appending all the X-Coordinates and all the Y-Coordinates. As the data is read across the screen, not down.
visuals[0].append([float(row[3]),float(row[5]),float(row[7]),float(row[9]),float(row[11]),float(row[13]),float(row[15]),float(row[17]),float(row[19]),float(row[21]),float(row[23]),float(row[25]),float(row[27]),float(row[29]),float(row[31]),float(row[33]),float(row[35]),float(row[37]),float(row[39]),float(row[41]),float(row[43])])
visuals[1].append([float(row[2]),float(row[4]),float(row[6]),float(row[8]),float(row[10]),float(row[12]),float(row[14]),float(row[16]),float(row[18]),float(row[20]),float(row[22]),float(row[24]),float(row[26]),float(row[28]),float(row[30]),float(row[32]),float(row[34]),float(row[36]),float(row[38]),float(row[40]),float(row[42])])
visuals[2].append([1,2])
#Create a list that contains all the X-Coordinates and all the Y-Coordinates. The 2nd list indicates the row. So visuals[1][100] would be the 100th row.
Y = visuals[1][0]
X = visuals[0][0]
fig, ax = plt.subplots(figsize = (8,8))
plt.grid(False)
# Create scatter plot
scatter = ax.scatter(visuals[0][0], visuals[1][0], c=['white'], alpha = 0.7, s = 20, edgecolor = 'black', zorder = 2)
#Create 2d Histogram
data = (X, Y)
data,x,y,p = plt.hist2d(X,Y, bins = 15, range = np.array([(-90, 90), (0, 140)]))
#Smooth with filter
im = plt.imshow(data.T, interpolation = 'gaussian', origin = 'lower', extent = [-80,80,0,140])
ax.set_ylim(0,140)
ax.set_xlim(-85,85)
#Define animation.
def animate(i) :
scatter.set_offsets([[[[[[[[[[[[[[[[[[[[[visuals[0][0+i][0], visuals[1][0+i][0]], [visuals[0][0+i][1], visuals[1][0+i][1]], [visuals[0][0+i][2], visuals[1][0+i][2]], [visuals[0][0+i][3], visuals[1][0+i][3]], [visuals[0][0+i][4], visuals[1][0+i][4]],[visuals[0][0+i][5], visuals[1][0+i][5]], [visuals[0][0+i][6], visuals[1][0+i][6]], [visuals[0][0+i][7], visuals[1][0+i][7]], [visuals[0][0+i][8], visuals[1][0+i][8]], [visuals[0][0+i][9], visuals[1][0+i][9]], [visuals[0][0+i][10], visuals[1][0+i][10]], [visuals[0][0+i][11], visuals[1][0+i][11]], [visuals[0][0+i][12], visuals[1][0+i][12]], [visuals[0][0+i][13], visuals[1][0+i][13]], [visuals[0][0+i][14], visuals[1][0+i][14]], [visuals[0][0+i][15], visuals[1][0+i][15]], [visuals[0][0+i][16], visuals[1][0+i][16]], [visuals[0][0+i][17], visuals[1][0+i][17]], [visuals[0][0+i][18], visuals[1][0+i][18]], [visuals[0][0+i][19], visuals[1][0+i][19]], [visuals[0][0+i][20], visuals[1][0+i][20]]]]]]]]]]]]]]]]]]]]]])
# This is were I'm having trouble...How do I animate the image derived from the 2d histogram
im.set_array[i+1]
ani = animation.FuncAnimation(fig, animate, np.arange(0,1000),
interval = 100, blit = False)
The image can be updated with im.set_data(data), where you need to call hist2d to get the updated data to pass to im. As a minimal example,
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation
X = np.random.randn(100000)
Y = np.random.randn(100000) + 5
fig, ax = plt.subplots(figsize = (8,8))
#Create 2d Histogram
data,x,y = np.histogram2d(X,Y, bins = 15)
#Smooth with filter
im = plt.imshow(data.T, interpolation = 'gaussian', origin = 'lower')
#Define animation.
def animate(i) :
X = np.random.randn(100000)
Y = np.random.randn(100000) + 5
data,x,y = np.histogram2d(X,Y, bins = 15)
im.set_data(data)
ani = animation.FuncAnimation(fig, animate, np.arange(0,1000),
interval = 100, blit = False)
plt.show()
Related
I am trying to animate a histogram using matplotlib and I want to show the different bars using a colormap, e.g:
I have this working when I clear the complete figure every frame and then redraw everything. But this is very slow, so I am trying out the example by matplotlib itself.
This works and is very fast, but unfortunately I have no idea on how to specify a colormap because it is using the patches.PathPatch object to draw the histogram now. I can only get it to work with the same single color for every individual bar.
How can I specify a gradient or colormap to achieve the desired result shown above?
Here is an example of a working animation with a single color which I am currently using.
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.patches as patches
import matplotlib.path as path
import matplotlib.animation as animation
# Fixing random state for reproducibility
np.random.seed(19680801)
# histogram our data with numpy
data = np.random.randn(1000)
n, bins = np.histogram(data, 100)
# get the corners of the rectangles for the histogram
left = np.array(bins[:-1])
right = np.array(bins[1:])
bottom = np.zeros(len(left))
top = bottom + n
nrects = len(left)
nverts = nrects * (1 + 3 + 1)
verts = np.zeros((nverts, 2))
codes = np.ones(nverts, int) * path.Path.LINETO
codes[0::5] = path.Path.MOVETO
codes[4::5] = path.Path.CLOSEPOLY
verts[0::5, 0] = left
verts[0::5, 1] = bottom
verts[1::5, 0] = left
verts[1::5, 1] = top
verts[2::5, 0] = right
verts[2::5, 1] = top
verts[3::5, 0] = right
verts[3::5, 1] = bottom
patch = None
def animate(i):
# simulate new data coming in
data = np.random.randn(1000)
n, bins = np.histogram(data, 100)
top = bottom + n
verts[1::5, 1] = top
verts[2::5, 1] = top
return [patch, ]
fig, ax = plt.subplots()
barpath = path.Path(verts, codes)
patch = patches.PathPatch(
barpath, facecolor='green', edgecolor='yellow', alpha=0.5)
ax.add_patch(patch)
ax.set_xlim(left[0], right[-1])
ax.set_ylim(bottom.min(), top.max())
ani = animation.FuncAnimation(fig, animate, 100, repeat=False, blit=True)
plt.show()
I recommend u using BarContainer, you can change bar color individually. In your example, the path is single object, matplotlib seems not to support gradient color for a single patch (not sure though).
import numpy as np
import matplotlib.pyplot as plt
# Fixing random state for reproducibility
np.random.seed(19680801)
# histogram our data with numpy
data = np.random.randn(1000)
colors = plt.cm.coolwarm(np.linspace(0, 1, 100))
def animate(i):
data = np.random.randn(1000)
bc = ax.hist(data, 100)[2]
for i, e in enumerate(bc):
e.set_color(colors[i])
return bc
fig, ax = plt.subplots(1, 1, figsize=(7.2, 7.2))
ani = animation.FuncAnimation(fig, animate, 100, repeat=False, blit=True)
I tried to write a simple script which updates a scatter plot for every timestep t. I wanted to do it as simple as possible. But all it does is to open a window where I can see nothing. The window just freezes. It is maybe just an small error, but I can not find it.
The the data.dat has the format
x y
Timestep 1 1 2
3 1
Timestep 2 6 3
2 1
(the file contains just the numbers)
import numpy as np
import matplotlib.pyplot as plt
import time
# Load particle positioins
with open('//home//user//data.dat', 'r') as fp:
particles = []
for line in fp:
line = line.split()
if line:
line = [float(i) for i in line]
particles.append(line)
T = 100
numbParticles = 2
x, y = np.array([]), np.array([])
plt.ion()
plt.figure()
plt.scatter(x,y)
for t in range(T):
plt.clf()
for k in range(numbP):
x = np.append(x, particles[numbParticles*t+k][0])
y = np.append(y, particles[numbParticles*t+k][1])
plt.scatter(x,y)
plt.draw()
time.sleep(1)
x, y = np.array([]), np.array([])
The simplest, cleanest way to make an animation is to use the matplotlib.animation module.
Since a scatter plot returns a matplotlib.collections.PathCollection, the way to update it is to call its set_offsets method. You can pass it an array of shape (N, 2) or a list of N 2-tuples -- each 2-tuple being an (x,y) coordinate.
For example,
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation
T = 100
numbParticles = 2
particles = np.random.random((T,numbParticles)).tolist()
x, y = np.array([]), np.array([])
def init():
pathcol.set_offsets([[], []])
return [pathcol]
def update(i, pathcol, particles):
pathcol.set_offsets(particles[i])
return [pathcol]
fig = plt.figure()
xs, ys = zip(*particles)
xmin, xmax = min(xs), max(xs)
ymin, ymax = min(ys), max(ys)
ax = plt.axes(xlim=(xmin, xmax), ylim=(ymin, ymax))
pathcol = plt.scatter([], [], s=100)
anim = animation.FuncAnimation(
fig, update, init_func=init, fargs=(pathcol, particles), interval=1000, frames=T,
blit=True, repeat=True)
plt.show()
I finally found a solution. You can do it simply by using this script. I tried to keep it simple:
import numpy as np
import matplotlib.pyplot as plt
from matplotlib.animation import FuncAnimation
# Helps me to get the data from the file I want to plot
N = 0
# Load particle positioins
with open('//home//user//data.dat', 'r') as fp:
particles = []
for line in fp:
line = line.split()
particles.append(line)
# Create new Figure and an Axes which fills it.
fig = plt.figure(figsize=(7, 7))
ax = fig.add_axes([0, 0, 1, 1], frameon=True)
border = 100
ax.set_xlim(-border, border), ax.set_xticks([])
ax.set_ylim(-border, border), ax.set_yticks([])
# particle data
p = 18 # number of particles
myPa = np.zeros(p, dtype=[('position', float, 2)])
# Construct the scatter which we will update during animation
scat = ax.scatter(myPa['position'][:, 0], myPa['position'][:, 1])
def update(frame_number):
# New positions
myPa['position'][:] = particles[N*p:N*p+p]
# Update the scatter collection, with the new colors, sizes and positions.
scat.set_offsets(myPa['position'])
increment()
def increment():
global N
N = N+1
# Construct the animation, using the update function as the animation director.
animation = FuncAnimation(fig, update, interval=20)
plt.show()
I am trying to animate annotations from a list of xy coordinates. The code below animates the annotation line but I cannot get the arrow function to animate using the same code.
The example dataset is a representation of the data I'm using. It is horizontally formatted. With this, I make a list from all the X-Coordinates and all the Y-Coordiantes from each subject. I then make a list pertaining to each time point, which is each row of data. From that I can plot a scatter and annotations.
However, when trying to plot an arrow between two separate coordinates I run into the error as stated by #ImportanceOfBeingErnest. The function should be a tuple of two elements but I'm having trouble with the arrow animation function as I think I need to provide 4 elements. The X and Y coordinate for the first point and X and Y coordinate for the second point.
Will I have to re-format that data or is there a way to animate the arrow function were 4 tuples are required?
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation
x_data = np.random.randint(80, size=(400, 4))
y_data = np.random.randint(80, size=(400, 4))
lists = [[],[]]
lists[0] = x_data
lists[1] = y_data
fig, ax = plt.subplots(figsize = (8,6))
ax.set_xlim(0,80)
ax.set_ylim(0,80)
scatter = ax.scatter(lists[0][0], lists[1][0], zorder = 5) #Scatter plot
annotation = ax.annotate(' Subject 1', xy=(lists[0][0][2],lists[1][0][2]))
arrow = ax.annotate('', xy = (lists[0][0][0], lists[1][0][0]), xytext = (lists[0][0][1],lists[1][0][1]), arrowprops = {'arrowstyle': "<->"})
def animate(i) :
scatter.set_offsets([[[[[lists[0][0+i][0], lists[1][0+i][0]], [lists[0][0+i][1], lists[1][0+i][1]], [lists[0][0+i][2], lists[1][0+i][2]], [lists[0][0+i][3], lists[1][0+i][3]]]]]])
Subject_x = lists[0][0+i][2]
Subject_y = lists[1][0+i][2]
annotation.set_position((Subject_x, Subject_y))
annotation.xy = (Subject_x, Subject_y)
Arrow1 = (lists[0][0+i][0], lists[1][0+i][0]) #Code for arrow animation doesn't work. Produces a blank screen after the 1st frame
Arrow2 = (lists[0][0+i][1], lists[1][0+i][1])
arrow.set_position((Arrow1, Arrow2))
arrow.xy = (Arrow1, Arrow2)
ani = animation.FuncAnimation(fig, animate,
interval = 50, blit = False)
plt.show()
The solution to this is still given in this question:
Animate points with labels with mathplotlib
As said several times in the comments, each position is determined by a tuple of two values (x,y). Hence you cannot provide a tuple of tuples to those positions. Also the start and end of the arrow should of course be at different positions.
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation
x_data = np.random.randint(80, size=(400, 4))
y_data = np.random.randint(80, size=(400, 4))
fig, ax = plt.subplots(figsize = (8,6))
ax.set_xlim(0,80)
ax.set_ylim(0,80)
scatter = ax.scatter(x_data[0], y_data[0], zorder = 5) #Scatter plot
annotation = ax.annotate(' Subject 1', xy=(x_data[0,2],y_data[0,2]))
arrow = ax.annotate('', xy = (x_data[0,0], y_data[0,0]),
xytext = (x_data[0,1],y_data[0,1]),
arrowprops = {'arrowstyle': "<->"})
def animate(i) :
scatter.set_offsets(np.c_[x_data[i,:], y_data[i,:]])
annotation.set_position((x_data[i,2], y_data[i,2]))
start = (x_data[i,0], y_data[i,0])
end = (x_data[i,1], y_data[i,1])
arrow.set_position(start)
arrow.xy = end
ani = animation.FuncAnimation(fig, animate, frames=len(x_data),
interval = 700, blit = False)
plt.show()
Consider the following code which implements ArtistAnimation to animate two different subplots within the same figure object.
import numpy as np
import itertools
import matplotlib.pyplot as plt
import matplotlib.mlab as ml
import matplotlib.animation as animation
def f(x,y,a):
return ((x/a)**2+y**2)
avals = np.linspace(0.1,1,10)
xaxis = np.linspace(-2,2,9)
yaxis = np.linspace(-2,2,9)
xy = itertools.product(xaxis,yaxis)
xy = list(map(list,xy))
xy = np.array(xy)
x = xy[:,0]
y = xy[:,1]
fig, [ax1,ax2] = plt.subplots(2)
ims = []
for a in avals:
xi = np.linspace(min(x), max(x), len(x))
yi = np.linspace(min(y), max(y), len(y))
zi = ml.griddata(x, y, f(x, y, a), xi, yi, interp='linear') # turn it into grid data, this is what imshow takes
title = plt.text(35,-4,str(a), horizontalalignment = 'center')
im1 = ax1.imshow(zi, animated = True, vmin = 0, vmax = 400)
im2 = ax2.imshow(zi, animated=True, vmin=0, vmax=400)
ims.append([im1,im2, title])
ani = animation.ArtistAnimation(fig, ims, interval = 1000, blit = False)
plt.show()
In this case the number of items in im1 and im2 are the same, and the frame rate for each subplot is identical.
Now, imagine I have 2 lists with different numbers of items, and that I wish ArtistAnimate to go through the frames in the same total time. Initially I thought of manipulating the interval keyword in the ArtistAnimation call but this implies that you can set different intervals for different artists, which I don't think is possible.
Anyway, I think the basic idea is pretty clear len(im1) is not equal to len(im2), but the animation needs to go through them all in the same amount of time.
Is there any way to do this please? Thanks
EDIT
While I try out the answer provided below, I should add that I would rather use ArtistAnimation due to the structure of my data. If there are no alternatives I will revert to the solution below.
Yes that is possible, kinda, using Funcanimation and encapsulating your data inside func.
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation
arr1 = np.random.rand(300,3,4)
arr2 = np.random.rand(200,5,6)
fig, (ax1, ax2) = plt.subplots(1,2)
img1 = ax1.imshow(arr1[0])
img2 = ax2.imshow(arr2[0])
# set relative display rates
r1 = 2
r2 = 3
def animate(ii):
if ii % r1:
img1.set_data(arr1[ii/r1])
if ii % r2:
img2.set_data(arr2[ii/r2])
return img1, img2
ani = animation.FuncAnimation(fig, func=animate, frames=np.arange(0, 600))
plt.show()
I tried to write a simple script which updates a scatter plot for every timestep t. I wanted to do it as simple as possible. But all it does is to open a window where I can see nothing. The window just freezes. It is maybe just an small error, but I can not find it.
The the data.dat has the format
x y
Timestep 1 1 2
3 1
Timestep 2 6 3
2 1
(the file contains just the numbers)
import numpy as np
import matplotlib.pyplot as plt
import time
# Load particle positioins
with open('//home//user//data.dat', 'r') as fp:
particles = []
for line in fp:
line = line.split()
if line:
line = [float(i) for i in line]
particles.append(line)
T = 100
numbParticles = 2
x, y = np.array([]), np.array([])
plt.ion()
plt.figure()
plt.scatter(x,y)
for t in range(T):
plt.clf()
for k in range(numbP):
x = np.append(x, particles[numbParticles*t+k][0])
y = np.append(y, particles[numbParticles*t+k][1])
plt.scatter(x,y)
plt.draw()
time.sleep(1)
x, y = np.array([]), np.array([])
The simplest, cleanest way to make an animation is to use the matplotlib.animation module.
Since a scatter plot returns a matplotlib.collections.PathCollection, the way to update it is to call its set_offsets method. You can pass it an array of shape (N, 2) or a list of N 2-tuples -- each 2-tuple being an (x,y) coordinate.
For example,
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation
T = 100
numbParticles = 2
particles = np.random.random((T,numbParticles)).tolist()
x, y = np.array([]), np.array([])
def init():
pathcol.set_offsets([[], []])
return [pathcol]
def update(i, pathcol, particles):
pathcol.set_offsets(particles[i])
return [pathcol]
fig = plt.figure()
xs, ys = zip(*particles)
xmin, xmax = min(xs), max(xs)
ymin, ymax = min(ys), max(ys)
ax = plt.axes(xlim=(xmin, xmax), ylim=(ymin, ymax))
pathcol = plt.scatter([], [], s=100)
anim = animation.FuncAnimation(
fig, update, init_func=init, fargs=(pathcol, particles), interval=1000, frames=T,
blit=True, repeat=True)
plt.show()
I finally found a solution. You can do it simply by using this script. I tried to keep it simple:
import numpy as np
import matplotlib.pyplot as plt
from matplotlib.animation import FuncAnimation
# Helps me to get the data from the file I want to plot
N = 0
# Load particle positioins
with open('//home//user//data.dat', 'r') as fp:
particles = []
for line in fp:
line = line.split()
particles.append(line)
# Create new Figure and an Axes which fills it.
fig = plt.figure(figsize=(7, 7))
ax = fig.add_axes([0, 0, 1, 1], frameon=True)
border = 100
ax.set_xlim(-border, border), ax.set_xticks([])
ax.set_ylim(-border, border), ax.set_yticks([])
# particle data
p = 18 # number of particles
myPa = np.zeros(p, dtype=[('position', float, 2)])
# Construct the scatter which we will update during animation
scat = ax.scatter(myPa['position'][:, 0], myPa['position'][:, 1])
def update(frame_number):
# New positions
myPa['position'][:] = particles[N*p:N*p+p]
# Update the scatter collection, with the new colors, sizes and positions.
scat.set_offsets(myPa['position'])
increment()
def increment():
global N
N = N+1
# Construct the animation, using the update function as the animation director.
animation = FuncAnimation(fig, update, interval=20)
plt.show()