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Expression of type Lambda

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

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, Lambda, f, fx, x
from proveit.logic import Equals, Image, SetOfAll
In [2]:
# build up the expression from sub-expressions
expr = Lambda([f, A], Equals(Image(f, A), SetOfAll(instance_param_or_params = [x], instance_element = fx, domain = A)))
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, A\right) \mapsto \left(f^{\rightarrow}(A) = \left\{f\left(x\right)\right\}_{x \in A}\right)
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameters: 7
body: 1
1Operationoperator: 2
operands: 3
2Literal
3ExprTuple4, 5
4Operationoperator: 6
operands: 7
5Operationoperator: 8
operand: 10
6Literal
7ExprTuple14, 19
8Literal
9ExprTuple10
10Lambdaparameter: 18
body: 11
11Conditionalvalue: 12
condition: 13
12Operationoperator: 14
operand: 18
13Operationoperator: 16
operands: 17
14Variable
15ExprTuple18
16Literal
17ExprTuple18, 19
18Variable
19Variable