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

# This notebook does not use Tatoeba data. Instead, it provides some functions that you may want to use in other notebooks. You can check how to:
# - [Save your data into a file you can download](#write_csv)

# Run the following cell to be able to run the examples.

# In[ ]:


import pandas as pd


# <a id='write_csv'></a>
# # Write a dataframe into a file that can be retrieved

# It is very simple to write a dataframe to a CSV file. 
# 
# Suppose you have the following dataframe

# In[ ]:


df = pd.DataFrame({'name': ['Raphael', 'Donatello'],
                    'mask': ['red', 'purple'],
                    'weapon': ['sai', 'bo staff']})
df


# You can use the `to_csv` function to write your dataframe to a CSV file. If you have some Python knowledge, you can check the [documentation](https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.DataFrame.to_csv.html). Otherwise, the following examples are the most used. 
# 
# After running the `to_csv` function, go back to the `Home` page. All files in the current folder are displayed there, so you should see your `Data_export.csv` file. If you want to download it, simply check the box on its left and click the `Download` button at the top of the list.

# ### 1. Write everything

# Simply specify the name of the file you want to create.

# In[ ]:


df.to_csv('Data_export.csv')


# This will give you the following content

# In[ ]:


get_ipython().system("cat 'Data_export.csv'")


# ### 2. Do not write the index

# The index of a dataframe is the first column on the left (in bold). In some situations, it is a useless information so you can ignore it when you export your data to a file. To do so, add the `index=False` parameter.

# In[ ]:


df.to_csv('Data_export.csv', index=False)


# This will give you the following content

# In[ ]:


get_ipython().system("cat 'Data_export.csv'")


# ### 3. Do not write the headers

# If you don't need the column headers, add the `header=None` parameter.

# In[ ]:


df.to_csv('Data_export.csv', index=False, header=None)


# This will give you the following content

# In[ ]:


get_ipython().system("cat 'Data_export.csv'")


# ### 4. Change the separator

# The default separator is the comma `,` (hence, CSV :) ). If you want to change it, you can use `sep='<character>'`. Note: a tabulation is represented by `\t`.

# In[ ]:


df.to_csv('Data_export.csv', index=False, header=None, sep='\t')


# This will give you the following content

# In[ ]:


get_ipython().system("cat 'Data_export.csv'")