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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, V, Variable, a, i
from proveit.core_expr_types import a_1_to_i
from proveit.linear_algebra import Norm, TensorProd
from proveit.logic import And, Equals, InSet
from proveit.numbers import Mult, one
In [2]:
# build up the expression from sub-expressions
sub_expr1 = Variable("_a", latex_format = r"{_{-}a}")
sub_expr2 = IndexedVar(a, sub_expr1)
expr = Conditional(Equals(Norm(TensorProd(a_1_to_i)), Mult(ExprRange(sub_expr1, Norm(sub_expr2), one, i))), And(ExprRange(sub_expr1, InSet(sub_expr2, IndexedVar(V, sub_expr1)), 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\{\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) \textrm{ if } \left(a_{1} \in V_{1}\right) \land  \left(a_{2} \in V_{2}\right) \land  \ldots \land  \left(a_{i} \in V_{i}\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
operands: 4
2Operationoperator: 5
operands: 6
3Literal
4ExprTuple7, 8
5Literal
6ExprTuple9
7Operationoperator: 28
operand: 14
8Operationoperator: 11
operands: 12
9ExprRangelambda_map: 13
start_index: 26
end_index: 27
10ExprTuple14
11Literal
12ExprTuple15
13Lambdaparameter: 34
body: 16
14Operationoperator: 17
operands: 18
15ExprRangelambda_map: 19
start_index: 26
end_index: 27
16Operationoperator: 20
operands: 21
17Literal
18ExprTuple22
19Lambdaparameter: 34
body: 23
20Literal
21ExprTuple31, 24
22ExprRangelambda_map: 25
start_index: 26
end_index: 27
23Operationoperator: 28
operand: 31
24IndexedVarvariable: 30
index: 34
25Lambdaparameter: 34
body: 31
26Literal
27Variable
28Literal
29ExprTuple31
30Variable
31IndexedVarvariable: 32
index: 34
32Variable
33ExprTuple34
34Variable