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Expression of type Conditional

from the theory of proveit.linear_algebra.tensors

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, V, Variable, a, i
from proveit.core_expr_types import V_1_to_i, a_1_to_i
from proveit.linear_algebra import InnerProdSpaces, Norm, TensorProd
from proveit.logic import And, Equals, Forall, InClass
from proveit.numbers import Mult, one
In [2]:
# build up the expression from sub-expressions
sub_expr1 = Variable("_a", latex_format = r"{_{-}a}")
expr = Conditional(Forall(instance_param_or_params = [a_1_to_i], instance_expr = Equals(Norm(TensorProd(a_1_to_i)), Mult(ExprRange(sub_expr1, Norm(IndexedVar(a, sub_expr1)), one, i))), domains = [V_1_to_i]).with_wrapping(), And(ExprRange(sub_expr1, InClass(IndexedVar(V, sub_expr1), InnerProdSpaces(K)), one, i)))
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\{\begin{array}{l}\forall_{\left(a_{1} \in V_{1}\right), \left(a_{2} \in V_{2}\right), \ldots, \left(a_{i} \in V_{i}\right)}~\\
\left(\left \|a_{1} {\otimes}  a_{2} {\otimes}  \ldots {\otimes}  a_{i}\right \| = \left(\left \|a_{1}\right \| \cdot  \left \|a_{2}\right \| \cdot  \ldots \cdot  \left \|a_{i}\right \|\right)\right)\end{array} \textrm{ if } \left(V_{1} \underset{{\scriptscriptstyle c}}{\in} \textrm{InnerProdSpaces}\left(K\right)\right) \land  \left(V_{2} \underset{{\scriptscriptstyle c}}{\in} \textrm{InnerProdSpaces}\left(K\right)\right) \land  \ldots \land  \left(V_{i} \underset{{\scriptscriptstyle c}}{\in} \textrm{InnerProdSpaces}\left(K\right)\right)\right..
In [5]:
stored_expr.style_options()
namedescriptiondefaultcurrent valuerelated methods
condition_delimiter'comma' or 'and'commacomma('with_comma_delimiter', 'with_conjunction_delimiter')
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Conditionalvalue: 1
condition: 2
1Operationoperator: 3
operand: 6
2Operationoperator: 15
operands: 5
3Literal
4ExprTuple6
5ExprTuple7
6Lambdaparameters: 34
body: 8
7ExprRangelambda_map: 9
start_index: 42
end_index: 43
8Conditionalvalue: 10
condition: 11
9Lambdaparameter: 50
body: 12
10Operationoperator: 13
operands: 14
11Operationoperator: 15
operands: 16
12Operationoperator: 17
operands: 18
13Literal
14ExprTuple19, 20
15Literal
16ExprTuple21
17Literal
18ExprTuple40, 22
19Operationoperator: 44
operand: 29
20Operationoperator: 24
operands: 25
21ExprRangelambda_map: 26
start_index: 42
end_index: 43
22Operationoperator: 27
operand: 32
23ExprTuple29
24Literal
25ExprTuple30
26Lambdaparameter: 50
body: 31
27Literal
28ExprTuple32
29Operationoperator: 33
operands: 34
30ExprRangelambda_map: 35
start_index: 42
end_index: 43
31Operationoperator: 36
operands: 37
32Variable
33Literal
34ExprTuple38
35Lambdaparameter: 50
body: 39
36Literal
37ExprTuple47, 40
38ExprRangelambda_map: 41
start_index: 42
end_index: 43
39Operationoperator: 44
operand: 47
40IndexedVarvariable: 46
index: 50
41Lambdaparameter: 50
body: 47
42Literal
43Variable
44Literal
45ExprTuple47
46Variable
47IndexedVarvariable: 48
index: 50
48Variable
49ExprTuple50
50Variable