#!/usr/bin/env python
# coding: utf-8

# This notebook is part of the `nbsphinx` documentation: https://nbsphinx.readthedocs.io/.

# # Code Cells
# 
# ## Code, Output, Streams
# 
# An empty code cell:

# In[ ]:





# Two empty lines:

# In[ ]:





# Leading/trailing empty lines:

# In[ ]:


# 2 empty lines before, 1 after


# A simple output:

# In[ ]:


6 * 7


# The standard output stream:

# In[ ]:


print('Hello, world!')


# Normal output + standard output

# In[ ]:


print('Hello, world!')
6 * 7


# The standard error stream is highlighted and displayed just below the code cell.
# The standard output stream comes afterwards (with no special highlighting).
# Finally, the "normal" output is displayed.

# In[ ]:


import sys

print("I'll appear on the standard error stream", file=sys.stderr)
print("I'll appear on the standard output stream")
"I'm the 'normal' output"


# <div class="alert alert-info">
# 
# **Note:**
# 
# Using the IPython kernel, the order is actually mixed up,
# see https://github.com/ipython/ipykernel/issues/280.
# 
# </div>

# ## Cell Magics
# 
# IPython can handle code in other languages by means of [cell magics](https://ipython.readthedocs.io/en/stable/interactive/magics.html#cell-magics):

# In[ ]:


get_ipython().run_cell_magic('bash', '', 'for i in 1 2 3\ndo\n    echo $i\ndone\n')


# ## Special Display Formats
# 
# See [IPython example notebook](https://nbviewer.jupyter.org/github/ipython/ipython/blob/master/examples/IPython Kernel/Rich Output.ipynb).

# ### Local Image Files
# 
# See also [SVG support for LaTeX](markdown-cells.ipynb#SVG-support-for-LaTeX).

# In[ ]:


from IPython.display import Image
i = Image(filename='images/notebook_icon.png')
i


# In[ ]:


display(i)


# ### Image URLs

# In[ ]:


Image(url='https://www.python.org/static/img/python-logo-large.png')


# In[ ]:


Image(url='https://www.python.org/static/img/python-logo-large.png', embed=True)


# In[ ]:


Image(url='http://jupyter.org/assets/nav_logo.svg')


# ### Math

# In[ ]:


from IPython.display import Math
eq = Math(r'\int\limits_{-\infty}^\infty f(x) \delta(x - x_0) dx = f(x_0)')
eq


# In[ ]:


display(eq)


# In[ ]:


from IPython.display import Latex
Latex(r'This is a \LaTeX{} equation: $a^2 + b^2 = c^2$')


# In[ ]:


get_ipython().run_cell_magic('latex', '', '\\begin{equation}\n\\int\\limits_{-\\infty}^\\infty f(x) \\delta(x - x_0) dx = f(x_0)\n\\end{equation}\n')


# ### Plots
# 
# The output formats for Matplotlib plots can be customized.
# You'll need separate settings for the Jupyter Notebook application and for `nbsphinx`.
# 
# If you want to use SVG images for Matplotlib plots,
# add this line to your IPython configuration file:
# 
# ```python
# c.InlineBackend.figure_formats = {'svg'}
# ```
# 
# If you want SVG images, but also want nice plots when exporting to LaTeX/PDF, you can select:
# 
# ```python
# c.InlineBackend.figure_formats = {'svg', 'pdf'}
# ```
# 
# If you want to use the default PNG plots or HiDPI plots using `'png2x'` (a.k.a. `'retina'`),
# make sure to set this:
# 
# ```python
# c.InlineBackend.rc = {'figure.dpi': 96}
# ```
# 
# This is needed because the default `'figure.dpi'` value of 72
# is only valid for the [Qt Console](https://qtconsole.readthedocs.io/).
# 
# If you are planning to store your SVG plots as part of your notebooks,
# you should also have a look at the `'svg.hashsalt'` setting.
# 
# For more details on these and other settings, have a look at
# [Default Values for Matplotlib's "inline" Backend](http://nbviewer.jupyter.org/github/mgeier/python-audio/blob/master/plotting/matplotlib-inline-defaults.ipynb).
# 
# The configuration file `ipython_kernel_config.py` can be either
# in the directory where your notebook is located
# (see the [ipython_kernel_config.py](ipython_kernel_config.py) in this directory),
# or in your profile directory
# (typically `~/.ipython/profile_default/ipython_kernel_config.py`).
# To find out your IPython profile directory, use this command:
# 
#     python3 -m IPython profile locate
# 
# A local `ipython_kernel_config.py` in the notebook directory
# also works on https://mybinder.org/.
# Alternatively, you can create a file with those settings in a file named
# `.ipython/profile_default/ipython_kernel_config.py` in your repository.
# 
# To get SVG and PDF plots for `nbsphinx`,
# use something like this in your `conf.py` file:
# 
# ```python
# nbsphinx_execute_arguments = [
#     "--InlineBackend.figure_formats={'svg', 'pdf'}",
#     "--InlineBackend.rc={'figure.dpi': 96}",
# ]
# ```
#     
# In the following example, `nbsphinx` should use an SVG image in the HTML output
# and a PDF image for LaTeX/PDF output.

# In[ ]:


import matplotlib.pyplot as plt


# In[ ]:


fig, ax = plt.subplots(figsize=[6, 3])
ax.plot([4, 9, 7, 20, 6, 33, 13, 23, 16, 62, 8]);


# Alternatively, the figure format(s) can also be chosen directly in the notebook
# (which overrides the setting in `nbsphinx_execute_arguments` and in the IPython configuration):

# In[ ]:


get_ipython().run_line_magic('config', "InlineBackend.figure_formats = ['png']")


# In[ ]:


fig


# If you want to use PNG images, but with HiDPI resolution,
# use the special `'png2x'` (a.k.a. `'retina'`) format
# (which also looks nice in the LaTeX output):

# In[ ]:


get_ipython().run_line_magic('config', "InlineBackend.figure_formats = ['png2x']")


# In[ ]:


fig


# ### Pandas Dataframes
# 
# [Pandas dataframes](http://pandas.pydata.org/pandas-docs/stable/dsintro.html#dataframe)
# should be displayed as nicely formatted HTML tables (if you are using HTML output).

# In[ ]:


import numpy as np
import pandas as pd


# In[ ]:


df = pd.DataFrame(np.random.randint(0, 100, size=[5, 4]),
                  columns=['a', 'b', 'c', 'd'])
df


# For LaTeX output, however, the plain text output is used by default.
# 
# To get nice LaTeX tables, a few settings have to be changed:

# In[ ]:


pd.set_option('display.latex.repr', True)


# This is not enabled by default because of
# [Pandas issue #12182](https://github.com/pandas-dev/pandas/issues/12182).
# 
# The generated LaTeX tables utilize the `booktabs` package, so you have to make sure that package is [loaded in the preamble](http://www.sphinx-doc.org/en/master/latex.html) with:
# 
#     \usepackage{booktabs}
# 
# In order to allow page breaks within tables, you should use:

# In[ ]:


pd.set_option('display.latex.longtable', True)


# The `longtable` package is already used by Sphinx,
# so you don't have to manually load it in the preamble.
# 
# Finally, if you want to use LaTeX math expressions in your dataframe, you'll have to disable escaping:

# In[ ]:


pd.set_option('display.latex.escape', False)


# The above settings should have no influence on the HTML output, but the LaTeX output should now look nicer:

# In[ ]:


df = pd.DataFrame(np.random.randint(0, 100, size=[10, 4]),
                  columns=[r'$\alpha$', r'$\beta$', r'$\gamma$', r'$\delta$'])
df


# ### YouTube Videos

# In[ ]:


from IPython.display import YouTubeVideo
YouTubeVideo('WAikxUGbomY')


# ### Arbitrary JavaScript Output (HTML only)

# In[ ]:


get_ipython().run_cell_magic('javascript', '', '\nvar text = document.createTextNode("Hello, I was generated with JavaScript!");\n// Content appended to "element" will be visible in the output area:\nelement.appendChild(text);\n')


# <div class="alert alert-info">
# 
# **Note:**
# 
# jQuery should be available, but using the readthedocs.org default theme, it's not. See [the issue on Github](https://github.com/rtfd/sphinx_rtd_theme/issues/328).
# Other Sphinx themes are not affected by this.
# 
# </div>

# ### Unsupported Output Types
# 
# If a code cell produces data with an unsupported MIME type, the Jupyter Notebook doesn't generate any output.
# `nbsphinx`, however, shows a warning message.

# In[ ]:


display({
    'text/x-python': 'print("Hello, world!")',
    'text/x-haskell': 'main = putStrLn "Hello, world!"',
}, raw=True)


# ## ANSI Colors
# 
# The standard output and standard error streams may contain [ANSI escape sequences](https://en.wikipedia.org/wiki/ANSI_escape_code) to change the text and background colors.

# In[ ]:


print('BEWARE: \x1b[1;33;41mugly colors\x1b[m!', file=sys.stderr)
print('AB\x1b[43mCD\x1b[35mEF\x1b[1mGH\x1b[4mIJ\x1b[7m'
      'KL\x1b[49mMN\x1b[39mOP\x1b[22mQR\x1b[24mST\x1b[27mUV')


# The following code showing the 8 basic ANSI colors is based on http://tldp.org/HOWTO/Bash-Prompt-HOWTO/x329.html.
# Each of the 8 colors has an "intense" variation, which is used for bold text.

# In[ ]:


text = ' XYZ '
formatstring = '\x1b[{}m' + text + '\x1b[m'

print(' ' * 6 + ' ' * len(text) +
      ''.join('{:^{}}'.format(bg, len(text)) for bg in range(40, 48)))
for fg in range(30, 38):
    for bold in False, True:
        fg_code = ('1;' if bold else '') + str(fg)
        print(' {:>4} '.format(fg_code) + formatstring.format(fg_code) +
              ''.join(formatstring.format(fg_code + ';' + str(bg))
                      for bg in range(40, 48)))


# ANSI also supports a set of 256 indexed colors.
# The following code showing all of them is based on http://bitmote.com/index.php?post/2012/11/19/Using-ANSI-Color-Codes-to-Colorize-Your-Bash-Prompt-on-Linux.

# In[ ]:


formatstring = '\x1b[38;5;{0};48;5;{0}mX\x1b[1mX\x1b[m'

print('  + ' + ''.join('{:2}'.format(i) for i in range(36)))
print('  0 ' + ''.join(formatstring.format(i) for i in range(16)))
for i in range(7):
    i = i * 36 + 16
    print('{:3} '.format(i) + ''.join(formatstring.format(i + j)
                                      for j in range(36) if i + j < 256))


# You can even use 24-bit RGB colors:

# In[ ]:


start = 255, 0, 0
end = 0, 0, 255
length = 79
out = []

for i in range(length):
    rgb = [start[c] + int(i * (end[c] - start[c]) / length) for c in range(3)]
    out.append('\x1b['
               '38;2;{rgb[2]};{rgb[1]};{rgb[0]};'
               '48;2;{rgb[0]};{rgb[1]};{rgb[2]}mX\x1b[m'.format(rgb=rgb))
print(''.join(out))