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Expression of type Lambda

from the theory of proveit.linear_algebra.scalar_multiplication

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 Conditional, ExprRange, IndexedVar, K, Lambda, V, Variable, a, n, x
from proveit.core_expr_types import x_1_to_n
from proveit.linear_algebra import ScalarMult, VecAdd
from proveit.logic import Equals, Forall, InSet
from proveit.numbers import Natural, one
In [2]:
# build up the expression from sub-expressions
sub_expr1 = Variable("_a", latex_format = r"{_{-}a}")
expr = Lambda(n, Conditional(Forall(instance_param_or_params = [a], instance_expr = Forall(instance_param_or_params = [x_1_to_n], instance_expr = Equals(ScalarMult(a, VecAdd(x_1_to_n)), VecAdd(ExprRange(sub_expr1, ScalarMult(a, IndexedVar(x, sub_expr1)), one, n))).with_wrapping_at(2), domain = V), domain = K), InSet(n, 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())
n \mapsto \left\{\forall_{a \in K}~\left[\forall_{x_{1}, x_{2}, \ldots, x_{n} \in V}~\left(\begin{array}{c} \begin{array}{l} \left(a \cdot \left(x_{1} +  x_{2} +  \ldots +  x_{n}\right)\right) =  \\ \left(\left(a \cdot x_{1}\right) +  \left(a \cdot x_{2}\right) +  \ldots +  \left(a \cdot x_{n}\right)\right) \end{array} \end{array}\right)\right] \textrm{ if } n \in \mathbb{N}\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameter: 44
body: 2
1ExprTuple44
2Conditionalvalue: 3
condition: 4
3Operationoperator: 13
operand: 7
4Operationoperator: 37
operands: 6
5ExprTuple7
6ExprTuple44, 8
7Lambdaparameter: 47
body: 10
8Literal
9ExprTuple47
10Conditionalvalue: 11
condition: 12
11Operationoperator: 13
operand: 16
12Operationoperator: 37
operands: 15
13Literal
14ExprTuple16
15ExprTuple47, 17
16Lambdaparameters: 35
body: 18
17Variable
18Conditionalvalue: 19
condition: 20
19Operationoperator: 21
operands: 22
20Operationoperator: 23
operands: 24
21Literal
22ExprTuple25, 26
23Literal
24ExprTuple27
25Operationoperator: 45
operands: 28
26Operationoperator: 34
operands: 29
27ExprRangelambda_map: 30
start_index: 43
end_index: 44
28ExprTuple47, 31
29ExprTuple32
30Lambdaparameter: 51
body: 33
31Operationoperator: 34
operands: 35
32ExprRangelambda_map: 36
start_index: 43
end_index: 44
33Operationoperator: 37
operands: 38
34Literal
35ExprTuple39
36Lambdaparameter: 51
body: 40
37Literal
38ExprTuple48, 41
39ExprRangelambda_map: 42
start_index: 43
end_index: 44
40Operationoperator: 45
operands: 46
41Variable
42Lambdaparameter: 51
body: 48
43Literal
44Variable
45Literal
46ExprTuple47, 48
47Variable
48IndexedVarvariable: 49
index: 51
49Variable
50ExprTuple51
51Variable