logo

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 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)), one), And(ExprRange(sub_expr1, InSet(sub_expr2, IndexedVar(V, sub_expr1)), one, i), And(ExprRange(sub_expr1, Equals(Norm(sub_expr2), one), 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 \| = 1 \textrm{ if } \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}\right \| = 1\right) \land  \left(\left \|a_{2}\right \| = 1\right) \land  \ldots \land  \left(\left \|a_{i}\right \| = 1\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: 26
operands: 3
2Operationoperator: 10
operands: 4
3ExprTuple5, 29
4ExprTuple6, 7
5Operationoperator: 30
operand: 12
6ExprRangelambda_map: 9
start_index: 29
end_index: 24
7Operationoperator: 10
operands: 11
8ExprTuple12
9Lambdaparameter: 35
body: 13
10Literal
11ExprTuple14
12Operationoperator: 15
operands: 16
13Operationoperator: 17
operands: 18
14ExprRangelambda_map: 19
start_index: 29
end_index: 24
15Literal
16ExprTuple20
17Literal
18ExprTuple32, 21
19Lambdaparameter: 35
body: 22
20ExprRangelambda_map: 23
start_index: 29
end_index: 24
21IndexedVarvariable: 25
index: 35
22Operationoperator: 26
operands: 27
23Lambdaparameter: 35
body: 32
24Variable
25Variable
26Literal
27ExprTuple28, 29
28Operationoperator: 30
operand: 32
29Literal
30Literal
31ExprTuple32
32IndexedVarvariable: 33
index: 35
33Variable
34ExprTuple35
35Variable