Expression of type Conditional

from the theory of proveit.numbers.summation

import proveit
# Automation is not needed when building an expression:
proveit.defaults.automation = False # This will speed things up.
proveit.defaults.inline_pngs = False # Makes files smaller.
%load_expr # Load the stored expression as 'stored_expr'
# import Expression classes needed to build the expression
from proveit import Conditional, a, b, j
from proveit.logic import InSet
from proveit.numbers import Add, Interval, subtract, three

# build up the expression from sub-expressions
expr = Conditional(subtract(j, three), InSet(j, Interval(Add(a, three), Add(b, three))))

expr:

# check that the built expression is the same as the stored expression
assert expr == stored_expr
assert expr._style_id == stored_expr._style_id
print("Passed sanity check: expr matches stored_expr")

Passed sanity check: expr matches stored_expr

# Show the LaTeX representation of the expression for convenience if you need it.
print(stored_expr.latex())

\left\{j - 3 \textrm{ if } j \in \{a + 3~\ldotp \ldotp~b + 3\}\right..

stored_expr.style_options()

name	description	default	current value	related methods
condition_delimiter	'comma' or 'and'	comma	comma	('with_comma_delimiter', 'with_conjunction_delimiter')

# display the expression information
stored_expr.expr_info()

	core type	sub-expressions	expression
0	Conditional	value: 1 condition: 2
1	Operation	operator: 16 operands: 3
2	Operation	operator: 4 operands: 5
3	ExprTuple	7, 6
4	Literal
5	ExprTuple	7, 8
6	Operation	operator: 9 operand: 20
7	Variable
8	Operation	operator: 11 operands: 12
9	Literal
10	ExprTuple	20
11	Literal
12	ExprTuple	13, 14
13	Operation	operator: 16 operands: 15
14	Operation	operator: 16 operands: 17
15	ExprTuple	18, 20
16	Literal
17	ExprTuple	19, 20
18	Variable
19	Variable
20	Literal