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Expression of type Lambda

from the theory of proveit.logic.booleans.conjunction

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 A, C, Conditional, ExprRange, IndexedVar, Lambda, Variable, m, n
from proveit.core_expr_types import A_1_to_m, C_1_to_n
from proveit.logic import And, Boolean, Equals, FALSE, InSet
from proveit.numbers import one
In [2]:
# build up the expression from sub-expressions
sub_expr1 = Variable("_a", latex_format = r"{_{-}a}")
expr = Lambda([A_1_to_m, C_1_to_n], Conditional(Equals(And(A_1_to_m, FALSE, C_1_to_n), FALSE), And(ExprRange(sub_expr1, InSet(IndexedVar(A, sub_expr1), Boolean), one, m), ExprRange(sub_expr1, InSet(IndexedVar(C, sub_expr1), Boolean), one, n))))
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_{1}, A_{2}, \ldots, A_{m}, C_{1}, C_{2}, \ldots, C_{n}\right) \mapsto \left\{\left(A_{1} \land  A_{2} \land  \ldots \land  A_{m} \land \bot\land C_{1} \land  C_{2} \land  \ldots \land  C_{n}\right) = \bot \textrm{ if } \left(A_{1} \in \mathbb{B}\right) ,  \left(A_{2} \in \mathbb{B}\right) ,  \ldots ,  \left(A_{m} \in \mathbb{B}\right), \left(C_{1} \in \mathbb{B}\right) ,  \left(C_{2} \in \mathbb{B}\right) ,  \ldots ,  \left(C_{n} \in \mathbb{B}\right)\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameters: 1
body: 2
1ExprTuple15, 17
2Conditionalvalue: 3
condition: 4
3Operationoperator: 5
operands: 6
4Operationoperator: 11
operands: 7
5Literal
6ExprTuple8, 16
7ExprTuple9, 10
8Operationoperator: 11
operands: 12
9ExprRangelambda_map: 13
start_index: 23
end_index: 21
10ExprRangelambda_map: 14
start_index: 23
end_index: 24
11Literal
12ExprTuple15, 16, 17
13Lambdaparameter: 34
body: 18
14Lambdaparameter: 34
body: 19
15ExprRangelambda_map: 20
start_index: 23
end_index: 21
16Literal
17ExprRangelambda_map: 22
start_index: 23
end_index: 24
18Operationoperator: 26
operands: 25
19Operationoperator: 26
operands: 27
20Lambdaparameter: 34
body: 28
21Variable
22Lambdaparameter: 34
body: 29
23Literal
24Variable
25ExprTuple28, 30
26Literal
27ExprTuple29, 30
28IndexedVarvariable: 31
index: 34
29IndexedVarvariable: 32
index: 34
30Literal
31Variable
32Variable
33ExprTuple34
34Variable