You can use a semi-colon `;` to end the line. This suppresses the unwanted output when generating plots:

    plt.plot(I,&#39;o&#39;);

In general, using a semi-colon stops IPython from printing any output value from that line of a code block. For example, the executing the cell containing the code `1+1;` would not output `2`.

An alternative way would be to bind a variable to the plot:

    _ = plt.plot(a)

This way, IPython only shows you the plots and the name `_` is bound to the unwanted output.

Another way is to just write `plt.show()` at the end of your drawing code. It would take less symbols to type if you&#39;re generating many subplots and/or drawing many plots on a single subplot.

Old question...  
Well I prefer to use a &lt;code&gt;pass&lt;/code&gt; in the last line.

Not so small like &lt;code&gt;;&lt;/code&gt;, but, IMHO, more legible and yet short.

From what I understand both run small repeatable tasks in the cloud.

What reasons and in what situations might I want to choose one over the other?

Worker Role vs Web Job

I&#39;ve been trying to create a new database connection on workbench. However, every time I test a connection there is an error message that says

&gt; Failed to connect to mysql at 127.0.0.1:3306 with user root access denied for user &#39;root&#39;@&#39;localhost&#39;(using password:YES) 

I don&#39;t know what&#39;s the cause of this error. I have tried uninstalling and re-installing my workbench 6.1 and mysql server 5.6 but the error is still unsolved.

Failed to connect to mysql at 127.0.0.1:3306 with user root access denied for user &#39;root&#39;@&#39;localhost&#39;(using password:YES)

I am plotting a NumPy array of values, `I`, using IPython notebook in `%matplotlib` inline mode with the plot command `plt.plot(I,&#39;o&#39;)`. 

The resulting output is:  

    &lt;matplotlib.figure.Figure at 0x119e6ead0&gt;
    Out[159]:
    [&lt;matplotlib.lines.Line2D at 0x11ac57090&gt;,
     &lt;matplotlib.lines.Line2D at 0x11ac57310&gt;,
     &lt;matplotlib.lines.Line2D at 0x11ac57510&gt;,
     &lt;matplotlib.lines.Line2D at 0x11ac57690&gt;,
     &lt;matplotlib.lines.Line2D at 0x11ac57810&gt;,
     &lt;matplotlib.lines.Line2D at 0x11ac57990&gt;,
     &lt;matplotlib.lines.Line2D at 0x11ac57b10&gt;,
     ....
     ....
    ]

Then my plot shows up below these lines of output. 

Is there a way to just show the plot and hide the `&lt;matplotlib.lines.Line2D at ...&gt;` from the output?


How to hide &lt;matplotlib.lines.Line2D&gt; in IPython notebook

I am plotting a NumPy array of values, <code>I</code>, using IPython notebook in <code>%matplotlib</code> inline mode with the plot command <code>plt.plot(I,'o')</code>.
The resulting output is:
<pre><code class="hljs language-php-template">&#x3C;matplotlib.figure.Figure at 0x119e6ead0>
Out[159]:
[&#x3C;matplotlib.lines.Line2D at 0x11ac57090>,
 &#x3C;matplotlib.lines.Line2D at 0x11ac57310>,
 &#x3C;matplotlib.lines.Line2D at 0x11ac57510>,
 &#x3C;matplotlib.lines.Line2D at 0x11ac57690>,
 &#x3C;matplotlib.lines.Line2D at 0x11ac57810>,
 &#x3C;matplotlib.lines.Line2D at 0x11ac57990>,
 &#x3C;matplotlib.lines.Line2D at 0x11ac57b10>,
 ....
 ....
]
</code></pre>
Then my plot shows up below these lines of output.
Is there a way to just show the plot and hide the <code>&#x3C;matplotlib.lines.Line2D at ...></code> from the output?

What&#39;s the best practise to add a row and a column header to a grid of subplots generated in a loop in ``matplotlib``? I can think of a couple, but not particularly neat:

1. For columns, with a counter to your loop you can use ``set_title()`` for the first row only. For rows this doesn&#39;t work. You would have to draw ``text`` outside of the plots.
2. You add an extra row of subplots on top and an extra column of subplots on the left, and draw text in the middle of that subplot. 

Can you suggest a better alternative?

![enter image description here][1]


  [1]: http://i.stack.imgur.com/p2knC.png

Row and column headers in matplotlib&#39;s subplots

pip is not able to install packages correctly: Permission denied error

I would like to get the index of a 2 dimensional Numpy array that matches a row.  For example, my array is this:

    vals = np.array([[0, 0],
    				 [1, 0],
    				 [2, 0],
    				 [0, 1],
    				 [1, 1],
    				 [2, 1],
    				 [0, 2],
    				 [1, 2],
    				 [2, 2],
    				 [0, 3],
    				 [1, 3],
    				 [2, 3],
    				 [0, 0],
    				 [1, 0],
    				 [2, 0],
    				 [0, 1],
    				 [1, 1],
    				 [2, 1],
    				 [0, 2],
    				 [1, 2],
    				 [2, 2],
    				 [0, 3],
    				 [1, 3],
    				 [2, 3]])

I would like to get the index that matches the row [0, 1] which is index 3 and 15.  When I do something like `numpy.where(vals == [0 ,1])` I get...

    (array([ 0,  3,  3,  4,  5,  6,  9, 12, 15, 15, 16, 17, 18, 21]), array([0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0]))


I want index array([3, 15]).

Find matching rows in 2 dimensional numpy array

I am very new to python. I was trying to pass value from one method to another within the class. I searched about the issue but i could not get proper solution. Because in my code, &quot;if&quot; is calling class&#39;s method &quot;on_any_event&quot; that in return should call my another method &quot;dropbox_fn&quot;, which make use of the value from &quot;on_any_event&quot;. Will it work, if the &quot;dropbox_fn&quot; method is outside the class?

I will illustrate with code. 

    class MyHandler(FileSystemEventHandler):
     def on_any_event(self, event):
        srcpath=event.src_path
        print (srcpath, &#39;has been &#39;,event.event_type)
        print (datetime.datetime.now())
        #print srcpath.split(&#39; &#39;, 12 );
        filename=srcpath[12:]
        return filename # I tried to call the method. showed error like not callable 

     def dropbox_fn(self)# Or will it work if this methos is outside the class ?
        #this method uses &quot;filename&quot;
        
    if __name__ == &quot;__main__&quot;:
      path = sys.argv[1] if len(sys.argv) &gt; 1 else &#39;.&#39;
      print (&quot;entry&quot;)
      event_handler = MyHandler()
      observer = Observer()
      observer.schedule(event_handler, path, recursive=True)
      observer.start()
      try:
         while True:
             time.sleep(1)
      except KeyboardInterrupt:
        observer.stop()
      observer.join()

The main issue in here is.. I cannot call &quot;on_any_event&quot; method without event parameter. So rather than returning value, calling &quot;dropbox_fn&quot; inside &quot;on_any_event&quot; would be a better way. Can someone help with this?

Calling one method from another within same class in Python

I just got set up to use pytest with Python 2.6. It has worked well so far with the exception of handling &quot;import&quot; statements: I can&#39;t seem to get pytest to respond to imports in the same way that my program does.

My directory structure is as follows:
    
    src/
        main.py
        util.py
        test/
            test_util.py
        geom/
            vector.py
            region.py
            test/
                test_vector.py
                test_region.py

To run, I call `python main.py` from src/.

In main.py, I import both vector and region with

    from geom.region import Region
    from geom.vector import Vector

In vector.py, I import region with

    from geom.region import Region

These all work fine when I run the code in a standard run. However, when I call &quot;py.test&quot; from src/, it consistently exits with import errors.

---

## Some Problems and My Solution Attempts ##

My first problem was that, when running &quot;test/test_foo.py&quot;, py.test could not &quot;import foo.py&quot; directly. I solved this by using the &quot;imp&quot; tool. In &quot;test_util.py&quot;:

    import imp
    util = imp.load_source(&quot;util&quot;, &quot;util.py&quot;)

This works great for many files. It also seems to imply that when pytest is running &quot;path/test/test_foo.py&quot; to test &quot;path/foo.py&quot;, it is based in the directory &quot;path&quot;.

However, this fails for &quot;test_vector.py&quot;. Pytest can find and import the `vector` module, but it **cannot** locate any of `vector`&#39;s imports. The following imports (from &quot;vector.py&quot;) both fail when using pytest:

    from geom.region import *
    from region import *

These both give errors of the form

    ImportError: No module named [geom.region / region]

I don&#39;t know what to do next to solve this problem; my understanding of imports in Python is limited.

**What is the proper way to handle imports when using pytest?**

---

## Edit: Extremely Hacky Solution ##

In `vector.py`, I changed the import statement from

    from geom.region import Region

to simply

    from region import Region

This makes the import relative to the directory of &quot;vector.py&quot;.

Next, in &quot;test/test_vector.py&quot;, I add the directory of &quot;vector.py&quot; to the path as follows:

    import sys, os
    sys.path.append(os.path.realpath(os.path.dirname(__file__)+&quot;/..&quot;))

This enables Python to find &quot;../region.py&quot; from &quot;geom/test/test_vector.py&quot;.

This works, but it seems extremely problematic because I am adding a ton of new directories to the path. What I&#39;m looking for is either

1) An import strategy that is compatible with pytest, or

2) An option in pytest that makes it compatible with my import strategy

So I am leaving this question open for answers of these kinds.

Importing correctly with pytest

I have the following code:

    import matplotlib.pyplot as plt
    import matplotlib.image as mpimg
    import matplotlib.cm as cm

    img = mpimg.imread(&quot;lena.jpg&quot;)

    f, axarr = plt.subplots(2, 2)
    axarr[0,0].imshow(img, cmap = cm.Greys_r)
    axarr[0,0].set_title(&quot;Rank = 512&quot;)

    rank = 128
    new_img = prune_matrix(rank, img)
    axarr[0,1].imshow(new_img, cmap = cm.Greys_r)
    axarr[0,1].set_title(&quot;Rank = %s&quot; %rank)

    rank = 32
    new_img = prune_matrix(rank, img)
    axarr[1,0].imshow(new_img, cmap = cm.Greys_r)
    axarr[1,0].set_title(&quot;Rank = %s&quot; %rank)

    rank = 16
    new_img = prune_matrix(rank, img)
    axarr[1,1].imshow(new_img, cmap = cm.Greys_r)
    axarr[1,1].set_title(&quot;Rank = %s&quot; %rank)

    plt.show()

However, the result is pretty ugly because of the values on the axes:

![enter image description here][1]


  [1]: http://i.stack.imgur.com/2BDVr.jpg

How can I turn off axes values for all subplots simultaneously?

Turn off axes in subplots

How can I change the format of the numbers in the x-axis to be like `10,000` instead of `10000`?
Ideally, I would just like to do something like this:
    
    x = format((10000.21, 22000.32, 10120.54), &quot;#,###&quot;)

Here is the code:
 
    import matplotlib.pyplot as plt

    # create figure instance
    fig1 = plt.figure(1)
    fig1.set_figheight(15)
    fig1.set_figwidth(20)

    ax = fig1.add_subplot(2,1,1)

    x = 10000.21, 22000.32, 10120.54
    
    y = 1, 4, 15
    ax.plot(x, y)

    ax2 = fig1.add_subplot(2,1,2)

    x2 = 10434, 24444, 31234
    y2 = 1, 4, 9
    ax2.plot(x2, y2)

    fig1.show()

How do I format axis number format to thousands with a comma in matplotlib?

I&#39;m using `matplotlib` to plot data (using `plot` and `errorbar` functions) from Python.  I have to plot a set of totally separate and independent plots, and then adjust their `ylim` values so they can be easily visually compared.

How can I retrieve the `ylim` values from each plot, so that I can take the min and max of the lower and upper ylim values, respectively, and adjust the plots so they can be visually compared?

Of course, I could just analyze the data and come up with my own custom `ylim` values... but I&#39;d like to use `matplotlib` to do that for me.  Any suggestions on how to easily (and efficiently) do this?

Here&#39;s my Python function that plots using `matplotlib`:

    import matplotlib.pyplot as plt

    def myplotfunction(title, values, errors, plot_file_name):
    
        # plot errorbars
        indices = range(0, len(values))
        fig = plt.figure()
        plt.errorbar(tuple(indices), tuple(values), tuple(errors), marker=&#39;.&#39;)
    
        # axes
        axes = plt.gca()
        axes.set_xlim([-0.5, len(values) - 0.5])
        axes.set_xlabel(&#39;My x-axis title&#39;)
        axes.set_ylabel(&#39;My y-axis title&#39;)
    
        # title
        plt.title(title)
    
        # save as file
        plt.savefig(plot_file_name)
    
        # close figure
        plt.close(fig)

matplotlib get ylim values

I have this data frame `diamonds` which is composed of variables like `(carat, price, color)`, and I want to draw a scatter plot of `price` to `carat` for each `color`, which means different `color` has different color in the plot.

This is easy in `R` with `ggplot`:

    ggplot(aes(x=carat, y=price, color=color),  #by setting color=color, ggplot automatically draw in different colors
           data=diamonds) + geom_point(stat=&#39;summary&#39;, fun.y=median)

![enter image description here][1]

I wonder how could this be done in Python using `matplotlib` ?

PS:

I know about auxiliary plotting packages, such as `seaborn` and `ggplot for python`, and I don&#39;t prefer them, just want to find out if it is possible to do the job using `matplotlib` alone, ;P


  [1]: http://i.stack.imgur.com/HW43K.png

plot different color for different categorical levels using matplotlib

What are the alternatives for drawing a simple curve for a function like

    eq = function(x){x*x}

in R?

It sounds such an obvious question, but I could only find these related questions on stackoverflow, but they are all more specific

* https://stackoverflow.com/questions/18162400/plot-line-function-in-r
*  https://stackoverflow.com/questions/1853703/plotting-functions-on-top-of-datapoints-in-r 
* https://stackoverflow.com/questions/20109257/how-can-i-plot-a-function-in-r-with-complex-numbers
* https://stackoverflow.com/questions/18737357/how-to-plot-a-simple-piecewise-linear-function
* https://stackoverflow.com/questions/4049674/draw-more-than-one-function-curves-in-the-same-plot

I hope I didn&#39;t write a duplicate question.




How to plot a function curve in R

I have been asked to place a full border around my plot below:

![enter image description here][1]


  [1]: http://i.stack.imgur.com/YuFsg.png

Using `panel.border = element_rect(colour = &quot;black&quot;)` results in losing in the plot becoming blank.

I can&#39;t use `theme_bw()` as it does not have the same functionality as the usual theme, the code I am currently using is below:

    graph&lt;-ggplot(d,aes(x=d$AOE, y=d$MEI)
                )+
      geom_point(shape=20, size=3)+
      geom_rug()+
      annotate(&quot;text&quot;, x = -1.1, y = 14000, label = &quot;27/04/2011&quot;) +
      annotate(&quot;text&quot;, x = -1.3, y = 10400, label = &quot;03/04/1974&quot;) +
      xlab(&quot;MEI&quot;)+
      ylab(&quot;AOE&quot;)+
      scale_y_log10()+
      theme(axis.text.y   = element_text(size=14),
            axis.text.x   = element_text(size=14),
            axis.title.y  = element_text(size=14),
            axis.title.x  = element_text(size=14),
            panel.background = element_blank(),
            panel.grid.major = element_blank(), 
            panel.grid.minor = element_blank(),
            axis.line = element_line(colour = &quot;black&quot;)
      )
    
    graph 

Any advice on how to get a full black border would be very much appreciated! 

Add panel border to ggplot2

I have been playing with Numpy and matplotlib in the last few days. I am having problems trying to make matplotlib plot a function without blocking execution. I know there are already many threads here on SO asking similar questions, and I &#39;ve googled quite a lot but haven&#39;t managed to make this work.

I have tried using show(block=False) as some people suggest, but all I get is a frozen window. If I simply call show(), the result is plotted properly but execution is blocked until the window is closed. From other threads I &#39;ve read, I suspect that whether show(block=False) works or not depends on the backend. Is this correct? My back end is Qt4Agg. Could you have a look at my code and tell me if you see something wrong? Here is my code. Thanks for any help.

    from math import *
    from matplotlib import pyplot as plt
    print(plt.get_backend())
    
    
    
    def main():
        x = range(-50, 51, 1)
        for pow in range(1,5):   # plot x^1, x^2, ..., x^4
    
            y = [Xi**pow for Xi in x]
            print(y)
    
            plt.plot(x, y)
            plt.draw()
            #plt.show()             #this plots correctly, but blocks execution.
            plt.show(block=False)   #this creates an empty frozen window.
            _ = raw_input(&quot;Press [enter] to continue.&quot;)
    
    
    if __name__ == &#39;__main__&#39;:
        main()

PS. I forgot to say that I would like to update the existing window every time I plot something, instead of creating a new one.

Plotting in a non-blocking way with Matplotlib

I have a dataframe that looks like the following

       color  x   y
    0    red  0   0
    1    red  1   1
    2    red  2   2
    3    red  3   3
    4    red  4   4
    5    red  5   5
    6    red  6   6
    7    red  7   7
    8    red  8   8
    9    red  9   9
    10  blue  0   0
    11  blue  1   1
    12  blue  2   4
    13  blue  3   9
    14  blue  4  16
    15  blue  5  25
    16  blue  6  36
    17  blue  7  49
    18  blue  8  64
    19  blue  9  81

I ultimately want two lines, one blue, one red.  The red line should essentially be y=x and the blue line should be y=x^2

When I do the following:

    df.plot(x=&#39;x&#39;, y=&#39;y&#39;)

The output is this:

![][1]

Is there a way to make pandas know that there are two sets?  And group them accordingly.  I&#39;d like to be able to specify the column `color` as the set differentiator


  [1]: http://i.stack.imgur.com/SlPtV.png

Plotting multiple lines, in different colors, with pandas dataframe

This is my code

    from PIL import Image
    pil_im = Image.open(&#39;data/empire.jpg&#39;)

I would like to do some image manipulation on it, and then show it on screen.   
I am having problem with showing PIL Image in python notebook.    

I have tried:

    print pil_im

And just

    pil_im

But both just give me:

    &lt;PIL.JpegImagePlugin.JpegImageFile image mode=RGB size=569x800 at 0x10ECA0710&gt;

How to show PIL Image in ipython notebook

I have an ipython/jupyter notebook that I visualize using NBviewer.

How can I hide all the code from the notebook rendered by NBviewer, so that only the output of code (e.g. plots and tables) and the markdown cells are shown?

How to hide code from cells in ipython notebook visualized with nbviewer?

How do I reference a cell in a IPython notebook markdown?

I know how to make a reference to an external link. But is there a way to assign an ID to a cell and then refer to the cell in the markdown?

How to reference a IPython notebook cell in markdown?

My `Jupyter` notebooks installed with `python 2` kernel. I do not understand why. I might have messed something up when I did the install. I already have `python 3`  installed. How can I add it to `Jupyter`?
Here&#39;s a screenshot of what the default `Jupyter` insalled with `python3 -m install jupyter` and opened in the browser with `jupyter notebook`looks like:
[![enter image description here][1]][1]


  [1]: http://i.stack.imgur.com/BgGiR.png

How do I add python3 kernel to jupyter (IPython)

So, I&#39;ve been trying to save a jupyter notebook as PDF but I just can&#39;t figure out how to do this. The first thing I try is from the file menu just download as PDF, but doing that results in:

    nbconvert failed: PDF creating failed

the next thing I try is try to do the conversion from the Command Prompt like this

    $ ipython nbconvert --to latex --post PDF MyNotebook.ipynb 

but again, this results in an error message

    ImportError: No module named &#39;PDF&#39;

and if I try

    $ ipython nbconvert --to latex MyNotebook.ipynb 

this results in 

    IPython.nbconvert.utils.pandoc.PandocMissing: Pandoc wasn&#39;t found:
    Please check that pandoc is installed

if I try to install pandoc (`pip install pandoc`), this gives me

    ImportError: No module named &#39;ConfigParser&#39;

and this is where I get stuck because I just don&#39;t know what else to do.
Anyone have idea how to fix whatever is wrong?


IPython/Jupyter Problems saving notebook as PDF

I am using iPython notebook.  When I do this:

    df

I get a beautiful table with cells.  However, if i do this:

    df1
    df2 

it doesn&#39;t print the first beautiful table.  If I try this:

    print df1
    print df2

It prints out the table in a different format that spills columns over and makes the output very tall.  

Is there a way to force it to print out the beautiful tables for both datasets?

Content Type	Original Author	Original Content on Stackoverflow
Question	ROBOTPWNS	View Question on Stackoverflow
Solution 1 - Python	Alex Riley	View Answer on Stackoverflow
Solution 2 - Python	kurtosis	View Answer on Stackoverflow
Solution 3 - Python	marcio	View Answer on Stackoverflow

How to hide <matplotlib.lines.Line2D> in IPython notebook

Python Problem Overview

Python Solutions

Solution 1 - Python

Solution 2 - Python

Solution 3 - Python

Failed to connect to mysql at 127.0.0.1:3306 with user root access denied for user 'root'@'localhost'(using password:YES)

Worker Role vs Web Job

Attributions