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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, K, Lambda, V, k
from proveit.core_expr_types import Q__b_1_to_j, b_1_to_j, f__b_1_to_j
from proveit.linear_algebra import ScalarMult, VecSum
from proveit.linear_algebra.addition import vec_summation_b1toj_fQ
from proveit.logic import Equals, Implies, InSet
In [2]:
# build up the expression from sub-expressions
expr = Lambda(k, Conditional(Implies(InSet(vec_summation_b1toj_fQ, V), Equals(ScalarMult(k, vec_summation_b1toj_fQ), VecSum(index_or_indices = [b_1_to_j], summand = ScalarMult(k, f__b_1_to_j), condition = Q__b_1_to_j)).with_wrapping_at(1)).with_wrapping_at(2), InSet(k, K)))
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())
k \mapsto \left\{\begin{array}{c} \begin{array}{l} \left(\left[\sum_{b_{1}, b_{2}, \ldots, b_{j}~|~Q\left(b_{1}, b_{2}, \ldots, b_{j}\right)}~f\left(b_{1}, b_{2}, \ldots, b_{j}\right)\right] \in V\right) \Rightarrow  \\ \left(\begin{array}{c} \begin{array}{l} \left(k \cdot \left[\sum_{b_{1}, b_{2}, \ldots, b_{j}~|~Q\left(b_{1}, b_{2}, \ldots, b_{j}\right)}~f\left(b_{1}, b_{2}, \ldots, b_{j}\right)\right]\right) \\  = \left[\sum_{b_{1}, b_{2}, \ldots, b_{j}~|~Q\left(b_{1}, b_{2}, \ldots, b_{j}\right)}~\left(k \cdot f\left(b_{1}, b_{2}, \ldots, b_{j}\right)\right)\right] \end{array} \end{array}\right) \end{array} \end{array} \textrm{ if } k \in K\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameter: 31
body: 2
1ExprTuple31
2Conditionalvalue: 3
condition: 4
3Operationoperator: 5
operands: 6
4Operationoperator: 11
operands: 7
5Literal
6ExprTuple8, 9
7ExprTuple31, 10
8Operationoperator: 11
operands: 12
9Operationoperator: 13
operands: 14
10Variable
11Literal
12ExprTuple20, 15
13Literal
14ExprTuple16, 17
15Variable
16Operationoperator: 28
operands: 18
17Operationoperator: 22
operand: 21
18ExprTuple31, 20
19ExprTuple21
20Operationoperator: 22
operand: 25
21Lambdaparameters: 35
body: 24
22Literal
23ExprTuple25
24Conditionalvalue: 26
condition: 30
25Lambdaparameters: 35
body: 27
26Operationoperator: 28
operands: 29
27Conditionalvalue: 32
condition: 30
28Literal
29ExprTuple31, 32
30Operationoperator: 33
operands: 35
31Variable
32Operationoperator: 34
operands: 35
33Variable
34Variable
35ExprTuple36
36ExprRangelambda_map: 37
start_index: 38
end_index: 39
37Lambdaparameter: 43
body: 40
38Literal
39Variable
40IndexedVarvariable: 41
index: 43
41Variable
42ExprTuple43
43Variable