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Expression of type Lambda

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 Lambda, f, i, j
from proveit.core_expr_types import Len
from proveit.core_expr_types.tuples import general_range_of_ranges
from proveit.logic import Equals
from proveit.numbers import zero
In [2]:
# build up the expression from sub-expressions
expr = Lambda([f, i, j], Equals(Len(operands = general_range_of_ranges), zero).with_wrapping_at(1))
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, i, j\right) \mapsto \left(\begin{array}{c} \begin{array}{l} |\left(f\left(m, i\left(m\right)\right), f\left(m, i\left(m\right) + 1\right), \ldots, f\left(m, j\left(m\right)\right), f\left(m + 1, i\left(m + 1\right)\right), f\left(m + 1, i\left(m + 1\right) + 1\right), \ldots, f\left(m + 1, j\left(m + 1\right)\right), \ldots\ldots, f\left(n, i\left(n\right)\right), f\left(n, i\left(n\right) + 1\right), \ldots, f\left(n, j\left(n\right)\right)\right)| \\  = 0 \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
1ExprTuple22, 19, 20
2Operationoperator: 3
operands: 4
3Literal
4ExprTuple5, 6
5Operationoperator: 7
operands: 8
6Literal
7Literal
8ExprTuple9
9ExprRangelambda_map: 10
start_index: 11
end_index: 12
10Lambdaparameter: 24
body: 13
11Variable
12Variable
13ExprRangelambda_map: 14
start_index: 15
end_index: 16
14Lambdaparameter: 25
body: 18
15Operationoperator: 19
operand: 24
16Operationoperator: 20
operand: 24
17ExprTuple25
18Operationoperator: 22
operands: 23
19Variable
20Variable
21ExprTuple24
22Variable
23ExprTuple24, 25
24Variable
25Variable