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

# # Rotation of axis labels
# 
# The `angle` parameter in `element_text()` function allows to rotate the text. This functionality is currently available to rotate axis labels (i.e. for the `axis_text, axis_text_x, axis_text_y` parameters in a `theme()`).

# 1. [Default axis labels layout](#1.-Default-Axis-Labels-Layout)  
# 
# 2. [Layout labels for the discrete axis](#2.-Layout-labels-for-the-discrete-axis)  
#  
# 3. [Layout labels for continuous axis](#3.-Layout-labels-for-continuous-axis)

# In[1]:


import pandas as pd

from lets_plot import *


# In[2]:


LetsPlot.setup_html()
LetsPlot.set_theme(theme_light())


# In[3]:


df = pd.read_csv('https://raw.githubusercontent.com/JetBrains/lets-plot-docs/master/data/midwest.csv')
df.head(3)


# In[4]:


df['state'].unique()


# In[5]:


df['state'] = df['state'].map(
    {'IL': 'Illinois', 'IN':'Indiana', 'MI':'Michigan', 'OH': 'Ohio', 'WI' : 'Wisconsin'}
)


# In[6]:


def plot_matrix(plots=[], width=400, height=300, columns=2):
    bunch = GGBunch()
    for i in range(len(plots)):
        row = int(i / columns)
        column = i % columns
        bunch.add_plot(plots[i], column * width, row * height, width, height)
    return bunch.show()


angles = [0, 45, 90, -10]

highlight_axis_labels = theme(
    text=element_text(color='gray', size=13), 
    axis_text=element_text(color='blue')
)
    
def plot_with_text_angles(base_plot, text_elem_name):
    plots = []   
    for angle in angles:
        plots.append(
            base_plot + ggtitle("angle={0}".format(angle)) + theme(**{text_elem_name: element_text(angle=angle)})
        )
    return plot_matrix(plots)


# #### 1. Default Axis Labels Layout

# In[7]:


p = ggplot(df) + geom_jitter(aes('state', 'poptotal'), color='light_gray') + scale_y_log10()
p


# #### 2. Layout labels for the discrete axis

# Let's change rotation angle to check placement of labels on a discrete axis. Labels for the continuous will be disabled to avoid cluttering the plot.

# ##### Horizontal axis

# In[8]:


plot_with_text_angles(
    p + theme(axis_text_y='blank') + highlight_axis_labels, 
    'axis_text_x'
)


# In[9]:


# Change axis position

plot_with_text_angles(
    p + theme(axis_text_y='blank') + highlight_axis_labels + scale_x_discrete(position="top"), 
    'axis_text_x'
)


# ##### Vertical axis

# When the rotation angle is set to 90°, some labels are not displayed to avoid overlapping.

# In[10]:


plot_with_text_angles(
    p + theme(axis_text_y='blank') + highlight_axis_labels + coord_flip(),
    'axis_text_x'
)


# In[11]:


# Change axis position

plot_with_text_angles(
    p + theme(axis_text_y='blank') + highlight_axis_labels + scale_x_discrete(position="top") + coord_flip(),
    'axis_text_x'
)


# #### 3. Layout labels for continuous axis

# For continuous axis the number of labels varies depending on how many it can fit.

# ##### Horizontal axis

# Changing the angle of rotation changes the number of labels on the axis:
# 90° rotation allows to place more labels on the horizontal axis.

# In[12]:


plot_with_text_angles(
    p + theme(axis_text_x='blank') + highlight_axis_labels + coord_flip(),
    'axis_text_y'
)


# In[13]:


# Change axis position

plot_with_text_angles(
    p + theme(axis_text_x='blank') + highlight_axis_labels + coord_flip() + scale_y_log10(position='right'),
    'axis_text_y'
)


# ##### Vertical axis

# By changing the angle of rotation, thereby increasing the label heights, we get a reduction in the total number of labels on the vertical axis.

# In[14]:


plot_with_text_angles(
    p + theme(axis_text_x='blank') + highlight_axis_labels,
    'axis_text_y'
)


# In[15]:


# Change axis position

plot_with_text_angles(
    p + theme(axis_text_x='blank') + highlight_axis_labels + scale_y_log10(position='right'), 
    'axis_text_y'
)