I am using subplot to display some figures, however the labels are mixed with the last subplot, so the plots don't have equal size. and the previous 5 are not perfectly round circle.
Here's my code:
for i in range(6):
plt.subplot(231 + i)
plt.title("Department " + depts[i])
labels = ['Male', 'Female']
colors = ['#3498DB', '#E74C3C']
sizes = [male_accept_rates[i] / (male_accept_rates[i] + female_accept_rates[i]),
female_accept_rates[i] / (male_accept_rates[i] + female_accept_rates[i])]
patches, texts = plt.pie(sizes, colors=colors, startangle=90)
plt.axis('equal')
plt.tight_layout()
plt.legend(labels, loc="best")
plt.show()
And here's the output:
can anyone give me some advise? Much appreciated.
It appears plt.axis('equal') only applies to the last subplot. So your fix is to put that line of code in the loop.
So:
import numpy as np
import matplotlib.pyplot as plt
depts = 'abcdefg'
male_accept_rates = np.array([ 2, 3, 2, 3, 4, 5], float)
female_accept_rates= np.array([ 3, 3, 4, 3, 2, 4], float)
for i in range(6):
plt.subplot(231 + i)
plt.title("Department " + depts[i])
labels = ['Male', 'Female']
colors = ['#3498DB', '#E74C3C']
sizes = [male_accept_rates[i] / (male_accept_rates[i] + female_accept_rates[i]),
female_accept_rates[i] / (male_accept_rates[i] + female_accept_rates[i])]
patches, texts = plt.pie(sizes, colors=colors, startangle=90)
plt.axis('equal')
plt.tight_layout()
plt.legend(labels, loc="best")
plt.show()
Produces this now:
Related
Suppose something comes up in my plot that mandates that I change the height ratio between two subplots that I've generated within my plot. I've tried changing GridSpec's height ratio to no avail.
import matplotlib.pyplot as plt
from matplotlib.gridspec import GridSpec
fig = plt.figure()
gs = GridSpec(2, 1, height_ratios=[2, 1])
ax1 = fig.add_subplot(gs[0])
ax1 = fig.axes[0]
ax2 = fig.add_subplot(gs[1])
ax2 = fig.axes[1]
ax1.plot([0, 1], [0, 1])
ax2.plot([0, 1], [1, 0])
gs.height_ratios = [2, 5]
The last line has no effect on the plot ratio.
In my actual code, it is not feasible without major reworking to set the height_ratios to 2:5 ahead of time.
How do I get this to update like I want?
The axes of relevant subplots can be manipulated and adjusted to get new height ratios.
import matplotlib.pyplot as plt
from matplotlib.gridspec import GridSpec
fig = plt.figure()
gs = GridSpec(2, 1, height_ratios=[2, 1]) #nrows, ncols
ax1 = fig.add_subplot(gs[0])
ax1 = fig.axes[0]
ax2 = fig.add_subplot(gs[1])
ax2 = fig.axes[1]
ax1.plot([0, 1], [0, 1])
ax2.plot([0, 1], [1, 0])
# new height ratio: 2:5 is required for the 2 subplots
rw, rh = 2, 5
# get dimensions of the 2 axes
box1 = ax1.get_position()
box2 = ax2.get_position()
# current dimensions
w1,h1 = box1.x1-box1.x0, box1.y1-box1.y0
w2,h2 = box2.x1-box2.x0, box2.y1-box2.y0
top1 = box1.y0+h1
#top2 = box2.y0+h2
full_h = h1+h2 #total height
# compute new heights for each axes
new_h1 = full_h*rw/(rw + rh)
new_h2 = full_h*rh/(rw + rh)
#btm1,btm2 = box1.y0, box2.y0
new_bottom1 = top1-new_h1
# finally, set new location/dimensions of the axes
ax1.set_position([box1.x0, new_bottom1, w1, new_h1])
ax2.set_position([box2.x0, box2.y0, w2, new_h2])
plt.show()
The output for ratio: (2, 5):
The output for (2, 10):
I have been following the example provided in:
https://matplotlib.org/examples/api/barchart_demo.html
My problem is that I want to add edges to the bars. But when I set the
linewidth=1, edgecolor='black'
parameters, the edges are only applied to the first pair of bars, leaving the remaining pairs unchanged.
"""
========
Barchart
========
A bar plot with errorbars and height labels on individual bars
"""
import numpy as np
import matplotlib.pyplot as plt
N = 5
men_means = (20, 35, 30, 35, 27)
men_std = (2, 3, 4, 1, 2)
ind = np.arange(N) # the x locations for the groups
width = 0.35 # the width of the bars
fig, ax = plt.subplots()
rects1 = ax.bar(ind, men_means, width, color='r', yerr=men_std,linewidth=1, edgecolor='black')
women_means = (25, 32, 34, 20, 25)
women_std = (3, 5, 2, 3, 3)
rects2 = ax.bar(ind + width, women_means, width, color='y', yerr=women_std, linewidth=1, edgecolor='black')
# add some text for labels, title and axes ticks
ax.set_ylabel('Scores')
ax.set_title('Scores by group and gender')
ax.set_xticks(ind + width / 2)
ax.set_xticklabels(('G1', 'G2', 'G3', 'G4', 'G5'))
ax.legend((rects1[0], rects2[0]), ('Men', 'Women'))
def autolabel(rects):
"""
Attach a text label above each bar displaying its height
"""
for rect in rects:
height = rect.get_height()
ax.text(rect.get_x() + rect.get_width()/2., 1.05*height,
'%d' % int(height),
ha='center', va='bottom')
autolabel(rects1)
autolabel(rects2)
plt.show()
Thanks for your help.
David.
Here is my script to plot data from a Geogtiff file using basemap. The data is categorical and there are 13 categories within this domain. The problem is that some categories get bunched up into one colour and thus some resolution is lost.
Unfortunately, I do not know how to fix this. I read that plt.cm.get_cmp is better for discrete datasets but I have not gotten it to work unfortunately.
gtif = 'some_dir'
ds = gdal.Open(gtif)
data = ds.ReadAsArray()
gt = ds.GetGeoTransform()
proj = ds.GetProjection()
xres = gt[1]
yres = gt[5]
xmin = gt[0] + xres
xmax = gt[0] + (xres * ds.RasterXSize) - xres
ymin = gt[3] + (yres * ds.RasterYSize) + yres
ymax = gt[3] - yres
xy_source = np.mgrid[xmin:xmax+xres:xres, ymax+yres:ymin:yres]
ds = None
fig2 = plt.figure(figsize=[12, 11])
ax2 = fig2.add_subplot(111)
ax2.set_title("Land use plot")
bm2 = Basemap(ax=ax2,projection='cyl',llcrnrlat=ymin,urcrnrlat=ymax,llcrnrlon=xmin,urcrnrlon=xmax,resolution='l')
bm2.drawcoastlines(linewidth=0.2)
bm2.drawcountries(linewidth=0.2)
data_new=np.copy(data)
data_new[data_new==255] = 0
nbins = np.unique(data_new).size
cb =plt.cm.get_cmap('jet', nbins+1)
img2 =bm2.imshow(np.flipud(data_new), cmap=cb)
ax2.set_xlim(3, 6)
ax2.set_ylim(50,53)
plt.show()
labels = [str(i) for i in np.unique(data_new)]
cb2=bm2.colorbar(img2, "right", size="5%", pad='3%', label='NOAH Land Use Category')
cb2.set_ticklabels(labels)
cb2.set_ticks(np.unique(data_new))
Here are the categories that are found within the domain (numbered classes):
np.unique(data_new)
array([ 0, 1, 4, 5, 7, 10, 11, 12, 13, 14, 15, 16, 17], dtype=uint8)
Thanks so much for any help here. I have also attached the output image that shows the mismatch. (not working)
First, this colormap problem is independent of the use of basemap. The following is therefore applicable to any matplotlib plot.
The problem here is that creating a colormap from n values distributes those values equally over the colormap range. Some values from the image therefore fall into the same colorrange within the colormap.
To prevent this, one can generate a colormap with the initial number of categories as shown below.
import matplotlib.pyplot as plt
import numpy as np
import matplotlib.colors
# generate some data
data = np.array( [ 0, 1, 4, 5, 7, 10]*8 )
np.random.shuffle(data)
data = data.reshape((8,6))
# generate colormap and norm
unique = np.unique(data)
vals = np.arange(int(unique.max()+1))/float(unique.max())
cols = plt.cm.jet(vals)
cmap = matplotlib.colors.ListedColormap(cols, int(unique.max())+1)
norm=matplotlib.colors.Normalize(vmin=-0.5, vmax=unique.max()+0.5)
fig, ax = plt.subplots(figsize=(5,5))
im = ax.imshow(data, cmap=cmap, norm=norm)
for i in range(data.shape[0]):
for j in range(data.shape[1]):
ax.text(j,i,data[i,j], color="w", ha="center", va="center")
cb = fig.colorbar(im, ax=ax, norm=norm)
cb.set_ticks(unique)
plt.show()
This can be extended to exclude the colors not present in the image as follows:
import matplotlib.pyplot as plt
import numpy as np
import matplotlib.colors
# generate some data
data = np.array( [ 0, 1, 4, 5, 7, 10]*8 )
np.random.shuffle(data)
data = data.reshape((8,6))
unique, newdata = np.unique(data, return_inverse=1)
newdata = newdata.reshape(data.shape)
# generate colormap and norm
new_unique = np.unique(newdata)
vals = np.arange(int(new_unique.max()+1))/float(new_unique.max())
cols = plt.cm.jet(vals)
cmap = matplotlib.colors.ListedColormap(cols, int(new_unique.max())+1)
norm=matplotlib.colors.Normalize(vmin=-0.5, vmax=new_unique.max()+0.5)
fig, ax = plt.subplots(figsize=(5,5))
im = ax.imshow(newdata, cmap=cmap, norm=norm)
for i in range(newdata.shape[0]):
for j in range(newdata.shape[1]):
ax.text(j,i,data[i,j], color="w", ha="center", va="center")
cb = fig.colorbar(im, ax=ax, norm=norm)
cb.ax.set_yticklabels(unique)
plt.show()
I use bar3d() to plot a 3D barchart, and I'd like to flip the y axis. I've tried to use invert_yaxis(), but it seems effectless. I've also tried manually reverse the values in the list with [::-1], but it didn't help either. It keeps displaying the 3D barchart in the very same way.
Any idea how can I flip the y axis?
Here's an example how it's not working for me (not even with 3D line plots):
from matplotlib.pyplot import *
from mpl_toolkits.mplot3d.axes3d import Axes3D
fig1 = figure(1)
ax11 = subplot(2, 2, 1, projection='3d')
ax11.plot([1, 2, 3, 4], [1, 2, 3, 4])
ax12 = subplot(2, 2, 2, projection='3d')
ax12.invert_xaxis()
ax12.plot([1, 2, 3, 4], [1, 2, 3, 4])
ax21 = subplot(2, 2, 3)
ax21.plot([1, 2, 3, 4])
ax22 = subplot(2, 2, 4)
ax22.invert_xaxis()
ax22.plot([1, 2, 3, 4])
show()
And the plot looks like this: http://we.tl/cqSsecVy6P
Thanks,
Daniel
If I understand the question correctly I think the problem is that matplotlib rotates the 3D plot. To remedy this just set the initial viewing angle using ax.view_init(elev, azim). Taking the matplotlib hist3d demo then we just have
from mpl_toolkits.mplot3d import Axes3D
import matplotlib.pyplot as plt
import numpy as np
fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')
x, y = np.random.rand(2, 100) * 4
hist, xedges, yedges = np.histogram2d(x, y, bins=4)
elements = (len(xedges) - 1) * (len(yedges) - 1)
xpos, ypos = np.meshgrid(xedges[:-1]+0.25, yedges[:-1]+0.25)
xpos = xpos.flatten()
ypos = ypos.flatten()
zpos = np.zeros(elements)
dx = 0.5 * np.ones_like(zpos)
dy = dx.copy()
dz = hist.flatten()
ypos_inv = ypos
ax.bar3d(xpos, ypos, zpos, dx, dy, dz, color='b', zsort='average')
ax.view_init(ax.elev, ax.azim+90)
plt.show()
Here I have rotated the axis by 90 degrees which flips one of the axis but not the other.
I have a following code which produces a graph -
# imports specific to the plots in this example
import sys
import numpy as np
from matplotlib import cm
import matplotlib.pyplot as plt
resultsDirectory='results'
outputFile=resultsDirectory+".pdf"
axisLabelFontSize=16
borderWidth=0.0
# Twice as wide as it is tall.
fig = plt.figure(figsize=plt.figaspect(0.5))
ax = fig.add_subplot(111)
# Set up the Grid
[i.set_linewidth(borderWidth) for i in ax.spines.itervalues()]
unsatX=[680,2775,3821,680,4073,941,1202,1463]
unsatY=[1,1,1,4,1,2,2,2]
paretoX=[680, 1203, 1726, 4870]
paretoY=[10,7, 4,1]
satX=[4870,680,1727,1726,1203,680]
satY=[1,13,7,4,7,10]
typeX=[680, 1727]
typeY=[13, 7]
leftX=[680]
leftY=[12]
c = np.rec.fromarrays([paretoX, paretoY], names='x,y')
c.sort()
paretoX=c.x
paretoY=c.y
markrsz=8
l4, = plt.plot(paretoX, paretoY, '#000000', lw=2, label='Pareto Curve(unfolding, period locality)',markersize=markrsz,zorder = 10)
l1, = plt.plot(satX, satY, 'bo', label='Sat Points',markersize=markrsz,zorder = 10)
l2, = plt.plot(unsatX, unsatY, 'ro',marker='s',label='Unsat Points',markersize=markrsz,zorder = 10)
l5, = plt.plot(leftX, leftY, 'gp',label='Proc. count pareto points',markersize=markrsz)
l6, = plt.plot(typeX, typeY, 'w*',label='Modulo pareto points',markersize=markrsz,zorder=10)
leg=plt.legend(bbox_to_anchor=(0.,-0.200, 1., 1.102), loc=3, numpoints=1,
ncol=3, mode="expand", borderaxespad=0., fancybox=True, shadow=True,prop={'size':axisLabelFontSize})
rect = leg.get_frame()
rect.set_facecolor('#cccccc') # a grayscale intensity
#leg.set_frame_on(False)
latency=[680,2775,4870, 680,3821,4868, 680,1727,4341,4864, 680,1203,1726,1203, 680,4073,4334,4595,4856, 941,1202,1463,1724]
processor=[1, 1, 1,13, 1, 1, 7, 7, 1, 1, 4, 4, 4, 7,10,1, 1, 1, 1, 2, 2, 2, 2]
ax.set_xlabel('Period',size=axisLabelFontSize,labelpad=10)
ax.set_ylabel('Processors',size=axisLabelFontSize,labelpad=10)
ax.set_xlim(0, max(latency)+100)
ax.set_ylim(0, max(processor)+1)
# Set Border width zero
[i.set_linewidth(0) for i in ax.spines.itervalues()]
gridLineWidth=0.1
ax.set_axisbelow(False)
gridlines = ax.get_xgridlines()+ax.get_ygridlines()
#ax.set_axisbelow(True)
plt.setp(gridlines, 'zorder', 5)
ax.yaxis.grid(True, linewidth=gridLineWidth, linestyle='-', color='0.6',alpha='0.3')
ax.xaxis.grid(False)
ax.xaxis.set_ticks_position('none')
ax.yaxis.set_ticks_position('none')
fig.savefig(outputFile, format="pdf", bbox_inches='tight')
The legends in the plot get messed up.
Could someone tell me how do i fix a long legend entry which overwrites into area of other entry? What would be ideal if, I could do 3 legend entries in first row and two legend entries in the second row.
Besides the workaround found by the question author, a possibility is to add new lines for long labels:
...
l4, = plt.plot(paretoX, paretoY, '#000000', lw=2,
label='Pareto Curve \n(unfolding, period locality)',markersize=markrsz,zorder = 10)
...
The following modification to the code also solved my problem -
leg=plt.legend(bbox_to_anchor=(0.,-0.350, 1., 1.102), loc=3, numpoints=1, ncol=2 , borderaxespad=0., fancybox=True, shadow=True,prop={'size':axisLabelFontSize})