Matplotlib.plot not found - python-3.x

I installed Matplotlib via Anaconda from here: https://anaconda.org/conda-forge/matplotlib
I used the very first command in Anaconda prompt.
But when I tried to plot from python (Spyder) as the following, I get the message:
ModuleNotFoundError: No module named 'matplotlib.plot'
import numpy as np
import matplotlib.plot as plt
x = np.linspace(0, 2*np.pi, 100)
y = np.sin(x)
plt.plot(x,y)
I have installed numpy, pandas and such using the same method and they work well.
How can I fix this?
Thank you so much.

matplotlib.pyplot is a state-based interface to matplotlib. pyplot is mainly intended for interactive plots and simple cases of programmatic plot generation. Therefore, whenever trying to work with graphs and what is commonly known and informally often referred as matplotlib you should import matplotlib.pyplot as plt:
import numpy as np
import matplotlib.pyplot as plt
x = np.linspace(0, 2*np.pi, 100)
y = np.sin(x)
plt.plot(x,y)

Related

How do I make my plot look like this with matplotlib?

So right now I'm trying to simulate a Poisson process for an assignment, here's the code so far:
import matplotlib.pyplot as plt
import numpy as np
import seaborn as sns
y = np.arange(0,21,1)
x = np.cumsum(np.random.exponential(2,21))
print(y)
print(x)
sns.set()
plt.plot(x,y)
plt.show()
The problem arises when I try plotting it. The code above, as expected, produces a normal matplotlib plot that looks like this:
However I need it to look like this:
Is there an easy way of doing it? I tried messing with bar plots but was unable to produce something that looks good.
The graph that you are wanting to plot is called as step plot in matplotlib. In order to plot it replace plt.plot(x,y) with plt.step(x,y)
So, your code becomes:
import matplotlib.pyplot as plt
import numpy as np
import seaborn as sns
y = np.arange(0,21,1)
x = np.cumsum(np.random.exponential(2,21))
print(y)
print(x)
sns.set()
plt.step(x,y)
plt.show()

plt.show() not working in spyder 3.7(Anaconda 3)

I am new to Python and Spyder. I am using Python 3.7 (Anaconda 3). I cannot get my graph after labelling x & y axis using plt.show() & also plt.draw() does not work either.
import os
import numpy as np
import matplotlib.pyplot as plt
time=[1,2,4]
data_list_Ch4=[1,3,5]
plt.plot(time, data_list_Ch4)
plt.xlabel("Time")
plt.ylabel("Channel")
plt.show()
screen shot of Spyder ide

How to plot a function with the pandas library using Python 3

Please, I need some help, so I am still in the learning phase of the Python programming for Data Science. I tried plotting a function but I am getting this. Please, what can I do? I am using Python 3. I appreciate your insights, explanations.
import pandas as pd
import numpy as np
import matplotlib as mpl
import matplotlib.pyplot as plt
from matplotlib import rcParams
import seaborn as sb
mtcars = pd.read_csv('mtcars.csv')
mtcars.columns = ['Car names','mpg','cyl','disp','hp','drat','wt','qsec','vs','am','gear','carb']
mpg1 = mtcars['mpg']
print(mpg1.plot())
df = mtcars[['mpg','cyl','wt']]
print(df.plot())
When I run to see what the plot is like, this is what I get:
AxesSubplot(0.125,0.11;0.775x0.77)
Please can you explain? How can I see the plot?
Thank you so much
you shouldn't "print" the plot, instead you should just call mpg1.plot() (eventually follpwed by plt.show() if needed)

Matplotlib function visualtization changing with precision

So I was trying to map out some math functions in 3d using matplotlib when I noticed something... The 3d plot suddenly changed (more like broke) when I tried to fix a previous issue wherein I was encountering some 'missing surface' - a gap in the plot. The main question is this -- Is the 3d plot not showing the two peaks on higher precision due to some inherent computing limitations of Axes3d or some other reason? Also a secondary question -- Why am I encountering 'missing surfaces' near +1.25 and -1.25 in lower precision plot?
I have tried googling for it and referred a few posts but nothing came ot except more questions.
import numpy as np
import matplotlib as mpl
import matplotlib.pyplot as plt
from matplotlib import cm
from mpl_toolkits.mplot3d import Axes3D
X=np.arange(-2,+2,0.025)
## Use np.arange(-5,+5,0.25) to experience the 'surface loss' I mention but otherwise correct 2 spike plot at each of (0,-1) and (0,+1) for both X and Y
Y=np.arange(-2,+2,0.025)
X,Y=np.meshgrid(X,Y)
R=1+X**2-Y**2
S=R**2+4*(X**2)*(Y**2)
Z=R/S
fig=plt.figure()
ax=Axes3D(fig)
ax.plot_surface(X,Y,Z,rstride=1,cstride=1,cmap=cm.viridis,norm=mpl.colors.Normalize(vmin=-1.,vmax=1.))
##NORMALIZE Was essential to get the proper color range
plt.show()
plt.savefig('art3d.jpeg',bbox_inches='tight')
plt.savefig('art3d.svg',bbox_inches='tight')
The ideal result should be like this (shows the func and the plot)
https://i.stack.imgur.com/kVnYc.png
The two plots I'm getting could be seen when the code is run as I can't seem to add images presumably because of low reputation :(
Any and all help is appreciated.Thanks in advance.
First note that the function in use is different from the wolfram alpha output. So let's use the function shown in the screenshot. Then you can limit the data to the range you want to show.
import numpy as np
import matplotlib as mpl
import matplotlib.pyplot as plt
from matplotlib import cm
from mpl_toolkits.mplot3d import Axes3D
X = np.arange(-2,+2,0.025)
Y=np.arange(-2,+2,0.025)
X,Y=np.meshgrid(X,Y)
Z = -2*X*Y / ((2*X*Y)**2 + (X**2 - Y**2 + 1)**2)
Z[(Z < -1)] = -1
Z[(Z > 1)] = 1
fig=plt.figure()
ax=Axes3D(fig)
ax.plot_surface(X,Y,Z,rstride=1,cstride=1,cmap=cm.viridis,norm=mpl.colors.Normalize(vmin=-1.,vmax=1.))
plt.show()

Python exponential plot is wrong

I am new using python and try to do some plots. I realized, that a plot of a bump function is incorrect. I have no idea how python came to this result.
This is my 'code'
import matplotlib.pyplot as plt
import matplotlib as mpl
import numpy as np
import matplotlib.pyplot as plt
class MainBody():
x = np.linspace(0.0001,99.9999,1000)
result = np.exp((-1.0)/(x*(100.0-x)))
plt.plot(x,result)
plt.show()
I got this result
but I should get this
I know that Python is powerful but I think such simple things should work without occuring such errors, where is my mistake?
Thank you
Matthias
Use plt.ylim to set the y-limits. Otherwise, by default, matplotlib will try to show the entire dataset, whose y-limits go roughly from 0 to 1:
import matplotlib.pyplot as plt
import numpy as np
x = np.linspace(0.0001,99.9999,1000)
result = np.exp((-1.0)/(x*(100.0-x)))
plt.plot(x,result)
plt.ylim(0.9975, 0.9999)
plt.show()

Resources