logo

Expression of type Lambda

from the theory of proveit.core_expr_types.lambda_maps

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, Q, f, g
from proveit.core_expr_types import Q__a_1_to_i, Q__b_1_to_i, Q__c_1_to_i, a_1_to_i, b_1_to_i, c_1_to_i, f__a_1_to_i, f__b_1_to_i, g__a_1_to_i, g__c_1_to_i
from proveit.logic import Equals, Forall, Implies
In [2]:
# build up the expression from sub-expressions
expr = Lambda([f, g, Q], Implies(Forall(instance_param_or_params = [a_1_to_i], instance_expr = Equals(f__a_1_to_i, g__a_1_to_i), condition = Q__a_1_to_i), Equals(Lambda([b_1_to_i], Conditional(f__b_1_to_i, Q__b_1_to_i)), Lambda([c_1_to_i], Conditional(g__c_1_to_i, Q__c_1_to_i))).with_wrapping_at(2)).with_wrapping_at(2))
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(f, g, Q\right) \mapsto \left(\begin{array}{c} \begin{array}{l} \left[\forall_{a_{1}, a_{2}, \ldots, a_{i}~|~Q\left(a_{1}, a_{2}, \ldots, a_{i}\right)}~\left(f\left(a_{1}, a_{2}, \ldots, a_{i}\right) = g\left(a_{1}, a_{2}, \ldots, a_{i}\right)\right)\right] \Rightarrow  \\ \left(\begin{array}{c} \begin{array}{l} \left[\left(b_{1}, b_{2}, \ldots, b_{i}\right) \mapsto \left\{f\left(b_{1}, b_{2}, \ldots, b_{i}\right) \textrm{ if } Q\left(b_{1}, b_{2}, \ldots, b_{i}\right)\right..\right] =  \\ \left[\left(c_{1}, c_{2}, \ldots, c_{i}\right) \mapsto \left\{g\left(c_{1}, c_{2}, \ldots, c_{i}\right) \textrm{ if } Q\left(c_{1}, c_{2}, \ldots, c_{i}\right)\right..\right] \end{array} \end{array}\right) \end{array} \end{array}\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
1ExprTuple31, 32, 25
2Operationoperator: 3
operands: 4
3Literal
4ExprTuple5, 6
5Operationoperator: 7
operand: 10
6Operationoperator: 22
operands: 9
7Literal
8ExprTuple10
9ExprTuple11, 12
10Lambdaparameters: 33
body: 13
11Lambdaparameters: 24
body: 14
12Lambdaparameters: 26
body: 15
13Conditionalvalue: 16
condition: 17
14Conditionalvalue: 18
condition: 19
15Conditionalvalue: 20
condition: 21
16Operationoperator: 22
operands: 23
17Operationoperator: 25
operands: 33
18Operationoperator: 31
operands: 24
19Operationoperator: 25
operands: 24
20Operationoperator: 32
operands: 26
21Operationoperator: 25
operands: 26
22Literal
23ExprTuple27, 28
24ExprTuple29
25Variable
26ExprTuple30
27Operationoperator: 31
operands: 33
28Operationoperator: 32
operands: 33
29ExprRangelambda_map: 34
start_index: 40
end_index: 41
30ExprRangelambda_map: 35
start_index: 40
end_index: 41
31Variable
32Variable
33ExprTuple36
34Lambdaparameter: 47
body: 37
35Lambdaparameter: 47
body: 38
36ExprRangelambda_map: 39
start_index: 40
end_index: 41
37IndexedVarvariable: 42
index: 47
38IndexedVarvariable: 43
index: 47
39Lambdaparameter: 47
body: 44
40Literal
41Variable
42Variable
43Variable
44IndexedVarvariable: 45
index: 47
45Variable
46ExprTuple47
47Variable