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Expression of type Lambda

from the theory of proveit.physics.quantum.algebra

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 A, Conditional, Lambda, i, j, m, n
from proveit.core_expr_types import v_i, w_j
from proveit.linear_algebra import VecSum
from proveit.logic import InSet
from proveit.numbers import Interval, one
from proveit.physics.quantum import Bra, Ket, Qmult
In [2]:
# build up the expression from sub-expressions
expr = Lambda(i, Conditional(VecSum(index_or_indices = [j], summand = Qmult(Bra(w_j), A, Ket(v_i), Ket(w_j), Bra(v_i)), domain = Interval(one, n)), InSet(i, Interval(one, m))))
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())
i \mapsto \left\{\sum_{j=1}^{n} \left(\langle w_{j} \rvert \thinspace A \thinspace \lvert v_{i} \rangle \thinspace \lvert w_{j} \rangle \thinspace \langle v_{i} \rvert\right) \textrm{ if } i \in \{1~\ldotp \ldotp~m\}\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: 1
1Conditionalvalue: 2
condition: 3
2Operationoperator: 4
operand: 7
3Operationoperator: 16
operands: 6
4Literal
5ExprTuple7
6ExprTuple39, 8
7Lambdaparameter: 38
body: 9
8Operationoperator: 28
operands: 10
9Conditionalvalue: 11
condition: 12
10ExprTuple32, 13
11Operationoperator: 14
operands: 15
12Operationoperator: 16
operands: 17
13Variable
14Literal
15ExprTuple18, 19, 20, 21, 22
16Literal
17ExprTuple38, 23
18Operationoperator: 26
operand: 30
19Variable
20Operationoperator: 24
operand: 31
21Operationoperator: 24
operand: 30
22Operationoperator: 26
operand: 31
23Operationoperator: 28
operands: 29
24Literal
25ExprTuple30
26Literal
27ExprTuple31
28Literal
29ExprTuple32, 33
30IndexedVarvariable: 34
index: 38
31IndexedVarvariable: 36
index: 39
32Literal
33Variable
34Variable
35ExprTuple38
36Variable
37ExprTuple39
38Variable
39Variable