Develop Reference

Python Error ImportError: No module named skimage.io

When I run this program in Python, it show me this error:
ImportError: No module named skimage.io.
I have already run the command pip install scikit-image, but I still get this error. Can you please help me?
This is my code:
import matplotlib.pyplot as plt
import skimage.io as io
import skimage.color as color
parrots = io.imread('C:\Python27\Example\parrots.bmp')
parrots_hsv= skcolor.convert_colorspace(parrots, 'RGB','HSV')
fig, ax= plt.subplots(nclos = 2, figsize=('8,4'))
ax[0].imshow(parrots)
ax[0].set_title('original image')
restored_image =skcolore.convert_colorspace(parrots_hsv, 'HSV','RGB')
ax[1].imshow(restored_image)
ax[1].set_title('restored image')
plt.show()`enter code here`

I reproduced this error like so:
import math.sqrt as sq
print(sq(4))
Error:
File ".\Solution.py", line 1, in <module>
import math.sqrt as sq
ModuleNotFoundError: No module named 'math.sqrt'; 'math' is not a package
repaired by:
from math import sqrt as sq
print(sq(4))
So I presume if you changed your imports to the below code it might fix it:
from matplotlib import pyplot as plt
from skimage import io as io
from skimage import color as color
In addition, you might want to read a bit here for a simple explanation about imports.

Plot from mglearn

How can I save plot from mglearn? I tried this code but it does not work.
import numpy as np
import matplotlib.pyplot as plt
import mglearn
from fpdf import FPDF
f = mglearn.plots.plot_knn_classification(n_neighbors=3)
f.savefig("n_neighbors.pdf", bbox_inches='tight')
The error was AttributeError: 'NoneType' object has no attribute 'savefig'.
Thanks

As the mglearn package uses matplotlib.pyplot's plotting mechanics you can use their saving mechanics, like so.
mglearn.plots.plot_knn_classification(n_neighbors=3)
plt.savefig("n_neighbors.pdf", bbox_inches='tight')

from sklearn.neighbors import KNeighborsClassifier
import matplotlib.pyplot as plt
import mglearn.plots
import numpy as np
import mglearn
from fpdf import FPDF
X, y = mglearn.datasets.make_forge()
mglearn.plots.plot_knn_classification(n_neighbors=3)
plt.savefig("n_neighbors.pdf", bbox_inches='tight')
This code work.

scatter plot on map in django app raises basemap error

I created a scatter plot on indian map in jupyter notebook but when i am trying to run the same code in my djnago app. It raises
ModuleNotFoundError: No module named 'mpl_toolkits.basemap'
Here's the code:
import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.basemap import Basemap
# make up some data for scatter plot
lats = np.random.randint(6, 37, size=50)
lons = np.random.randint(68, 97, size=50)
fig = plt.gcf()
fig.set_size_inches(8, 6.5)
m = Basemap(projection='cyl', \
llcrnrlat=6., urcrnrlat=37., \
llcrnrlon=68., urcrnrlon=97., \
lat_ts=20, \
resolution='c',epsg=3857)
m.bluemarble(scale=1)
m.drawcoastlines(color='white', linewidth=0.2)
m.drawmapboundary(fill_color='#D3D3D3')
x, y = m(lons, lats)
plt.scatter(x, y, 10, marker='o', color='Red')
plt.show()
I am using the same conda interpreter in my django app. whats is the reason for this error ?

I use Anaconda under Win10. With a different OS or installation the solution may be different for you, but I can try to sketch the path.
You have to install Basemap. See here and here. For me conda install -c conda-forge basemap-data-hires did work.
When importing from mpl_toolkits.basemap import Basemap I got an error: KeyError: PROJ_LIB. Following the experiences here you must find a directory share with epsg inside. It is expected to be in the conda or the anaconda directory.
I did a search in my Anaconda3-dirctory and have found this path: "C:\Anaconda3\Library\share"
Then the following code did work for me (and your code gives a nice picture too :-) :
import os
proj_lib = "C:\Anaconda3\Library\share"
os.environ["PROJ_LIB"] = proj_lib
import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.basemap import Basemap
plt.figure(figsize=(8, 8))
m = Basemap(projection='ortho', resolution=None, lat_0=50, lon_0=-100)
m.bluemarble(scale=0.5);

Python script throws ValueError while plotting data

I have tried an example from the page 11 of tephigramDocs, but it raises a ValueError. The code is the following:
import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt
import os.path
import tephi
dew_point = os.path.join(tephi.DATA_DIR, ’dews.txt’)
dew_data = tephi.loadtxt(dew_point, column_titles=(’pressure’, ’dewpoint’))
dews = zip(dew_data.pressure, dew_data.dewpoint)
tpg = tephi.Tephigram()
tpg.plot(dews)
plt.show()
Clearly the format of data passed to the plot function is wrong but I cannot find a solution for this. The error message is:
ValueError: The environment profile data requires to be a sequence of pressure, temperature value pairs.

Matplotlib error "cannot import name pyplot" on Ubuntu

I am trying to run this code.
import numpy as np
import cv2
from matplotlib import pyplot as plt
img = cv2.imread('games.jpg',0)
plt.imshow(img, cmap = 'gray', interpolation = 'bicubic')
plt.xticks([]), plt.yticks([])
plt.show()
But I keep getting this error
Traceback (most recent call last):
File "mpl.py", line 3, in <module>
from matplotlib import pyplot as plt
File "/home/megha/matplotlib.py", line 3, in <module>
from matplotlib import pyplot as plt
ImportError: cannot import name pyplot
I googled a solution for this but I am only getting that the matplotlib version needs to be upgraded. I tried that too, and its still showing the same error.
I have also tried
import matplotlib.pyplot as plt but I have python 2.7 version, so that didnt work either.

Use import matplotlib.pyplot as plt instead.