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Expression of type Conditional

from the theory of proveit.linear_algebra.inner_products

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, v, w
from proveit.core_expr_types import x_1_to_n
from proveit.linear_algebra import InnerProd
from proveit.logic import And, Equals, InSet, Set
from proveit.numbers import KroneckerDelta
In [2]:
# build up the expression from sub-expressions
sub_expr1 = Set(x_1_to_n)
expr = Conditional(Equals(InnerProd(v, w), KroneckerDelta(v, w)), And(InSet(v, sub_expr1), InSet(w, sub_expr1)))
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 \langle v, w\right \rangle = \delta_{v, w} \textrm{ if } v \in \left\{x_{1}, x_{2}, \ldots, x_{n}\right\} ,  w \in \left\{x_{1}, x_{2}, \ldots, x_{n}\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, 10
7Operationoperator: 11
operands: 13
8Operationoperator: 12
operands: 13
9Operationoperator: 15
operands: 14
10Operationoperator: 15
operands: 16
11Literal
12Literal
13ExprTuple17, 18
14ExprTuple17, 19
15Literal
16ExprTuple18, 19
17Variable
18Variable
19Operationoperator: 20
operands: 21
20Literal
21ExprTuple22
22ExprRangelambda_map: 23
start_index: 24
end_index: 25
23Lambdaparameter: 29
body: 26
24Literal
25Variable
26IndexedVarvariable: 27
index: 29
27Variable
28ExprTuple29
29Variable