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Expression of type Lambda

from the theory of proveit.logic.sets.functions.bijections

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, B, Lambda, f
from proveit.logic import And, Bijections, Equals, InSet, Injections, Surjections
In [2]:
# build up the expression from sub-expressions
expr = Lambda(f, Equals(InSet(f, Bijections(A, B)), And(InSet(f, Injections(A, B)), InSet(f, Surjections(A, B)))).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())
f \mapsto \left(\begin{array}{c} \begin{array}{l} \left(f \in \left[A \xrightarrow[\text{onto}]{\text{1-to-1}} B\right]\right) =  \\ \left(\left(f \in \left[A \xrightarrow[]{\text{1-to-1}} B\right]\right) \land \left(f \in \left[A \xrightarrow[\text{onto}]{} B\right]\right)\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
0Lambdaparameter: 18
body: 2
1ExprTuple18
2Operationoperator: 3
operands: 4
3Literal
4ExprTuple5, 6
5Operationoperator: 15
operands: 7
6Operationoperator: 8
operands: 9
7ExprTuple18, 10
8Literal
9ExprTuple11, 12
10Operationoperator: 13
operands: 22
11Operationoperator: 15
operands: 14
12Operationoperator: 15
operands: 16
13Literal
14ExprTuple18, 17
15Literal
16ExprTuple18, 19
17Operationoperator: 20
operands: 22
18Variable
19Operationoperator: 21
operands: 22
20Literal
21Literal
22ExprTuple23, 24
23Variable
24Variable