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Expression of type Lambda

from the theory of proveit.numbers.addition.subtraction

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, b
from proveit.logic import NotEquals
from proveit.numbers import subtract, zero
In [2]:
# build up the expression from sub-expressions
expr = Lambda([a, b], Conditional(NotEquals(subtract(a, b), zero), NotEquals(a, b)))
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())
\left(a, b\right) \mapsto \left\{\left(a - b\right) \neq 0 \textrm{ if } a \neq b\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameters: 6
body: 1
1Conditionalvalue: 2
condition: 3
2Operationoperator: 5
operands: 4
3Operationoperator: 5
operands: 6
4ExprTuple7, 8
5Literal
6ExprTuple11, 15
7Operationoperator: 9
operands: 10
8Literal
9Literal
10ExprTuple11, 12
11Variable
12Operationoperator: 13
operand: 15
13Literal
14ExprTuple15
15Variable