pptree

This package allows to pretty-print a tree of python objects.

Install

pip install pptree

or

easy_install pptree

Documentation

This package provides:

• a default Node implementation
• a pretty_print function accepting a default Node or custom node as root

The Node class

__init__(self, name, parent=None)

• the name of the node to print
• the parent Node object (optional)

The pretty-print function

print_tree(current_node, childattr='children', nameattr='name', horizontal=True)

• the root node object
• the name of the list containing the children (optional)
• the name of the field containing the text to display. If nameattr is not filled and the custom node don't have any name field, then the str function is used. (optional)
• whether to print the tree horizontally or vertically (optional)

Example using provided Node class

from pptree import *

shame = Node("shame")

conscience = Node("conscience", shame)
selfdisgust = Node("selfdisgust", shame)
embarrassment = Node("embarrassment", shame)

selfconsciousness = Node("selfconsciousness", embarrassment)
shamefacedness = Node("shamefacedness", embarrassment)
chagrin = Node("chagrin", embarrassment)
discomfiture = Node("discomfiture", embarrassment)
abashment = Node("abashment", embarrassment)
confusion = Node("confusion", embarrassment)
  
print_tree(shame)

Output:

     ┌conscience
     ├self-disgust
shame┤
     │             ┌self-consciousness
     │             ├shamefacedness
     │             ├chagrin
     └embarrassment┤
                   ├discomfiture
                   ├abashment
                   └confusion

Example using custom node implementation

class Employee:

    def __init__(self, fullname, function, head=None):
        self.fullname = fullname
        self.function = function
        self.team = []
        if head:
            head.team.append(self)

    def __str__(self):
        return self.function

jean = Employee("Jean Dupont", "CEO")
isabelle = Employee("Isabelle Leblanc", "Sales", jean)
enzo = Employee("Enzo Riviera", "Technology", jean)
lola = Employee("Lola Monet", "RH", jean)
kevin = Employee("Kevin Perez", "Developer", enzo)
lydia = Employee("Lydia Petit", "Tester", enzo)

>>> print_tree(jean, "team")

    ┌Sales
    ├RH
 CEO┤
    │          ┌Developer
    └Technology┤
               └Tester

>>> print_tree(jean, "team", "fullname")

            ┌Isabelle Leblanc
            ├Lola Monet
 Jean Dupont┤
            │            ┌Kevin Perez
            └Enzo Riviera┤
                         └Lydia Petit

Example printing tree vertically

from pptree import *

shame = Node("shame")

conscience = Node("conscience", shame)
selfdisgust = Node("selfdisgust", shame)
embarrassment = Node("embarrassment", shame)

selfconsciousness = Node("selfconsciousness", embarrassment)
shamefacedness = Node("shamefacedness", embarrassment)
chagrin = Node("chagrin", embarrassment)
discomfiture = Node("discomfiture", embarrassment)
abashment = Node("abashment", embarrassment)
confusion = Node("confusion", embarrassment)
  
print_tree(shame, horizontal=False)

Output:

                       shame                                                                                     
    ┌─────────────┬──────┴─────────────────────────────────────────────┐                                         
conscience   selfdisgust                                             embarrassment                               
                                      ┌─────────────────┬─────────────┬────┴─────┬───────────┬────────────┐      
                              selfconsciousness   shamefacedness   chagrin   confusion   abashment   discomfiture

Using simple binary tree realisation

The Node class

def __init__(self, value=None):
    self.value = value
    self.left = None
    self.right = None

• the value of the node

def add(node, value):

• add new value to the node

So you can build binary tree from the root node

The pretty-print function

print_tree(current_node, nameattr='value', left_child='left', right_child='right')

• the root node object
• the name of the field containing the text to display. If nameattr is not filled and the custom node don't have any value field, then the str function is used. (optional)
• the left child attribute name
• the right child attribute name

print_tree recursively prints current_node.left and current_node.right elements, so you need to call it only with root node, like

>>> print_tree(root_node, nameattr='value')

Example

from ppbtree import *
from random import randint

root = Node()
    for _ in range(15):
        add(root, randint(10, 99))

>>> print_tree(root, nameattr='value')
      ┌11
   ┌25┤
   |  └30┐
   |     └40
 46┤
   |     ┌48
   |  ┌48┘
   └51┤
      |        ┌52
      |     ┌55┤
      |     |  └74
      |  ┌83┤
      |  |  └87┐
      |  |     └89
      └90┘