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Expression of type Forall

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

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, f
from proveit.logic import And, Equals, Forall, Functions, Image, InSet, Surjections
In [2]:
# build up the expression from sub-expressions
expr = Forall(instance_param_or_params = [f], instance_expr = Equals(InSet(f, Surjections(A, B)), And(InSet(f, Functions(A, B)), Equals(Image(f, 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())
\forall_{f}~\left(\begin{array}{c} \begin{array}{l} \left(f \in \left[A \xrightarrow[\text{onto}]{} B\right]\right) =  \\ \left(\left(f \in \left[A \rightarrow B\right]\right) \land \left(f^{\rightarrow}(A) = B\right)\right) \end{array} \end{array}\right)
In [5]:
stored_expr.style_options()
namedescriptiondefaultcurrent valuerelated methods
with_wrappingIf 'True', wrap the Expression after the parametersNoneNone/False('with_wrapping',)
condition_wrappingWrap 'before' or 'after' the condition (or None).NoneNone/False('with_wrap_after_condition', 'with_wrap_before_condition')
wrap_paramsIf 'True', wraps every two parameters AND wraps the Expression after the parametersNoneNone/False('with_params',)
justificationjustify to the 'left', 'center', or 'right' in the array cellscentercenter('with_justification',)
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Operationoperator: 1
operand: 3
1Literal
2ExprTuple3
3Lambdaparameter: 27
body: 5
4ExprTuple27
5Operationoperator: 18
operands: 6
6ExprTuple7, 8
7Operationoperator: 16
operands: 9
8Operationoperator: 10
operands: 11
9ExprTuple27, 12
10Literal
11ExprTuple13, 14
12Operationoperator: 15
operands: 23
13Operationoperator: 16
operands: 17
14Operationoperator: 18
operands: 19
15Literal
16Literal
17ExprTuple27, 20
18Literal
19ExprTuple21, 26
20Operationoperator: 22
operands: 23
21Operationoperator: 24
operands: 25
22Literal
23ExprTuple28, 26
24Literal
25ExprTuple27, 28
26Variable
27Variable
28Variable