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Expression of type Lambda

from the theory of proveit.numbers.number_sets.integers

In [1]:
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, Lambda, a
from proveit.logic import And, InSet
from proveit.numbers import Integer, NaturalPos, greater, zero
In [2]:
# build up the expression from sub-expressions
expr = Lambda(a, Conditional(InSet(a, NaturalPos), And(InSet(a, Integer), greater(a, zero))))
expr:
In [3]:
# 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
In [4]:
# Show the LaTeX representation of the expression for convenience if you need it.
print(stored_expr.latex())
a \mapsto \left\{a \in \mathbb{N}^+ \textrm{ if } a \in \mathbb{Z} ,  a > 0\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameter: 17
body: 2
1ExprTuple17
2Conditionalvalue: 3
condition: 4
3Operationoperator: 11
operands: 5
4Operationoperator: 6
operands: 7
5ExprTuple17, 8
6Literal
7ExprTuple9, 10
8Literal
9Operationoperator: 11
operands: 12
10Operationoperator: 13
operands: 14
11Literal
12ExprTuple17, 15
13Literal
14ExprTuple16, 17
15Literal
16Literal
17Variable