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Expression of type Lambda

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, Lambda, V, Variable, a, i
from proveit.core_expr_types import V_1_to_i, a_1_to_i
from proveit.linear_algebra import TensorProd
from proveit.logic import And, InSet
from proveit.numbers import one
In [2]:
# build up the expression from sub-expressions
sub_expr1 = Variable("_a", latex_format = r"{_{-}a}")
expr = Lambda([a_1_to_i], Conditional(InSet(TensorProd(a_1_to_i), TensorProd(V_1_to_i)), And(ExprRange(sub_expr1, InSet(IndexedVar(a, sub_expr1), 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(a_{1}, a_{2}, \ldots, a_{i}\right) \mapsto \left\{\left(a_{1} {\otimes}  a_{2} {\otimes}  \ldots {\otimes}  a_{i}\right) \in \left(V_{1} {\otimes}  V_{2} {\otimes}  \ldots {\otimes}  V_{i}\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()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameters: 10
body: 1
1Conditionalvalue: 2
condition: 3
2Operationoperator: 21
operands: 4
3Operationoperator: 5
operands: 6
4ExprTuple7, 8
5Literal
6ExprTuple9
7Operationoperator: 11
operands: 10
8Operationoperator: 11
operands: 12
9ExprRangelambda_map: 13
start_index: 19
end_index: 20
10ExprTuple14
11Literal
12ExprTuple15
13Lambdaparameter: 28
body: 16
14ExprRangelambda_map: 17
start_index: 19
end_index: 20
15ExprRangelambda_map: 18
start_index: 19
end_index: 20
16Operationoperator: 21
operands: 22
17Lambdaparameter: 28
body: 23
18Lambdaparameter: 28
body: 24
19Literal
20Variable
21Literal
22ExprTuple23, 24
23IndexedVarvariable: 25
index: 28
24IndexedVarvariable: 26
index: 28
25Variable
26Variable
27ExprTuple28
28Variable