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Expression of type Forall

from the theory of proveit.core_expr_types.tuples

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 i, j, n
from proveit.core_expr_types import Len, f_1_to_n, i_to_j_len
from proveit.core_expr_types.tuples import f_i_to_j__1_to_n
from proveit.logic import Equals, Forall, InSet
from proveit.numbers import Mult, Natural
In [2]:
# build up the expression from sub-expressions
expr = Forall(instance_param_or_params = [f_1_to_n, i, j], instance_expr = Equals(Len(operands = [f_i_to_j__1_to_n]), Mult(n, i_to_j_len)).with_wrapping_at(1), condition = InSet(i_to_j_len, Natural))
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_{1}, f_{2}, \ldots, f_{n}, i, j~|~\left(j - i + 1\right) \in \mathbb{N}}~\left(\begin{array}{c} \begin{array}{l} |\left(f_{1}\left(i\right), f_{1}\left(i + 1\right), \ldots, f_{1}\left(j\right), f_{2}\left(i\right), f_{2}\left(i + 1\right), \ldots, f_{2}\left(j\right), \ldots\ldots, f_{n}\left(i\right), f_{n}\left(i + 1\right), \ldots, f_{n}\left(j\right)\right)| \\  = \left(n \cdot \left(j - i + 1\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
3Lambdaparameters: 4
body: 5
4ExprTuple6, 36, 32
5Conditionalvalue: 7
condition: 8
6ExprRangelambda_map: 9
start_index: 30
end_index: 25
7Operationoperator: 10
operands: 11
8Operationoperator: 12
operands: 13
9Lambdaparameter: 41
body: 14
10Literal
11ExprTuple15, 16
12Literal
13ExprTuple23, 17
14IndexedVarvariable: 39
index: 41
15Operationoperator: 18
operands: 19
16Operationoperator: 20
operands: 21
17Literal
18Literal
19ExprTuple22
20Literal
21ExprTuple25, 23
22ExprRangelambda_map: 24
start_index: 30
end_index: 25
23Operationoperator: 26
operands: 27
24Lambdaparameter: 42
body: 28
25Variable
26Literal
27ExprTuple32, 29, 30
28ExprRangelambda_map: 31
start_index: 36
end_index: 32
29Operationoperator: 33
operand: 36
30Literal
31Lambdaparameter: 41
body: 35
32Variable
33Literal
34ExprTuple36
35Operationoperator: 37
operand: 41
36Variable
37IndexedVarvariable: 39
index: 42
38ExprTuple41
39Variable
40ExprTuple42
41Variable
42Variable