I've seen many times online that people use
import pylab
pylab.imshow(some_arg)
or
from pylab import *
imshow(some_arg)
but it gives the following error on my computer
NameError: name 'imshow' is not defined
however if I directly use matplotlib, it works fine
import matplotlib.pyplot as plt
plt.imshow(some_arg) # works fine
I've tried search about how pylab works, but there doesn't seem to be much information.
What should be the problem in my case?
Thank you.
Related
In the following code I'm getting errors when trying to call librosa.grifflim, telling me the attribute does not exist.
import os
from matplotlib import pyplot as plt
import librosa
import librosa.display
import IPython.display as ipd
import numpy as np
import cv2
S = cv2.imread('spectrograms/CantinaBand60.wav10.jpg')
D = librosa.amplitude_to_db(np.abs(S), ref=np.max)
signal = librosa.griffinlim(D)
sf.write('test.wav', signal, 352000)
I've upgraded librosa, and I still encounter the error. The documentation page for this function no longer seems to exist either. I've also tried import just that module using librosa.griffinlim but it continues to tell me this module doesn't exist. Was this function removed during a recent version? If so, is there another function I can use to apply the griffin lim algorithm?
librosa.griffinlim was introduced in librosa 0.7.0. So you need to have that version or later. You can check this using the following code.
import librosa; print(librosa.__version__)
I'm writing code in a Jupyter Notebook that involves cleaning and analyzing a large amount of consumer data. I'm trying to use dill to save the dataframes with thousands of rows so I don't have to run the code every time I want to make an adjustment, so dill seems like the perfect package to do so... Except I'm getting this error when attempting to pickle the notebook:
AttributeError: module 'dill' has no attribute 'dump_session'
Let me know if the program code is necessary - I don't think it should make a difference. The imports are:
import numpy as np
import pandas as pd
import dill
import scipy
from matplotlib import pyplot as plt
from __future__ import division
from collections import OrderedDict
from sklearn.cluster import KMeans
pd.options.display.max_columns = None
and when I run this code I get the error from above:
dill.dump_session('recengine.db')
Is there another package that's interfering with dill's use of pickle vs. cpickle?
I just started learning doing financial analytics with python today. I ran into a block of code and it requires importing numpy and matplotlib to run the codes and generate a graph(not sure if it really can).
The codes are like this:
import numpy as np
import matplotlib as mpl
import matplotlib.pyplot as plt
mpl.rcParams['font.family'] = 'serif'
K = 8000
S = np.linspace(7000,9000,100)
h = np.maximum(S-K, 0)
plt.figure()
plt.plot(S, h, lw=2.5)
plt.xlabel('index level $S-t$ at maturity')
plt.ylabel("inner value of European call option")
plt.grid(True)
I installed both numpy and matplotlib but after I tried running the codes nothing came out.
I really don't know what went wrong. This is my first time using numpy and matplotlib and I have not idea how to solve this problem.
Please help!
Title says it all, I somehow can not find that function. Obviously it's inside the Numpy package (numpy.core.umath.deg2rad) and I've tried importing it but to no avail. Anyone care to chime in?
import numpy as np - np.deg2rad doesn't even show up
from numpy import* - umath.deg2rad shows up, but it raises an error, ''name 'umath' is not defined''
from numpy.core.umath import deg2rad
# then
deg2rad(...)
Or
import numpy as np
np.core.umath.deg2rad(...)
I'm working to migrate from MatLab to python in Sage.
So I use these commands and I faced this error in Sage:
from scipy import misc
l = misc.lena();
import pylab as pl
pl.imshow(l)
The Error or message (i don't know) is:
matplotlib.image.AxesImage object at 0xb80198c
And it doesn't show any image
It's not an error, just print the object that method returned.
There are two ways to show the figure:
Add pl.show() after calling pl.imshow(l)
Use ipython --pylab to open your python shell,
That is an object being returned from pylab after using the "imshow" command. That is the location of the Axes image object.
documentation:
http://matplotlib.sourceforge.net/api/pyplot_api.html#matplotlib.pyplot.imshow
Looks like it says it displays the object to the current axes. If you havent already created a plot I imagine you wont see anything
Simple google search suggests this might be what you are looking for
http://docs.scipy.org/doc/scipy/reference/generated/scipy.misc.lena.html
from scipy import misc
l = misc.lena();
import pylab as pl
pl.imshow(l)
####use this
pl.show()