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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 one
In [2]:
# build up the expression from sub-expressions
sub_expr1 = Variable("_a", latex_format = r"{_{-}a}")
expr = Lambda(a, Conditional(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), InSet(a, 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())
a \mapsto \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) \textrm{ if } a \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: 39
body: 2
1ExprTuple39
2Conditionalvalue: 3
condition: 4
3Operationoperator: 5
operand: 8
4Operationoperator: 29
operands: 7
5Literal
6ExprTuple8
7ExprTuple39, 9
8Lambdaparameters: 27
body: 10
9Variable
10Conditionalvalue: 11
condition: 12
11Operationoperator: 13
operands: 14
12Operationoperator: 15
operands: 16
13Literal
14ExprTuple17, 18
15Literal
16ExprTuple19
17Operationoperator: 37
operands: 20
18Operationoperator: 26
operands: 21
19ExprRangelambda_map: 22
start_index: 35
end_index: 36
20ExprTuple39, 23
21ExprTuple24
22Lambdaparameter: 43
body: 25
23Operationoperator: 26
operands: 27
24ExprRangelambda_map: 28
start_index: 35
end_index: 36
25Operationoperator: 29
operands: 30
26Literal
27ExprTuple31
28Lambdaparameter: 43
body: 32
29Literal
30ExprTuple40, 33
31ExprRangelambda_map: 34
start_index: 35
end_index: 36
32Operationoperator: 37
operands: 38
33Variable
34Lambdaparameter: 43
body: 40
35Literal
36Variable
37Literal
38ExprTuple39, 40
39Variable
40IndexedVarvariable: 41
index: 43
41Variable
42ExprTuple43
43Variable