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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, Lambda, fi, i, x, y, z
from proveit.linear_algebra import TensorProd
from proveit.logic import Equals, InSet
from proveit.numbers import Interval, four, two
In [2]:
# build up the expression from sub-expressions
expr = Lambda(i, Conditional(Equals(TensorProd(x, y, fi, z), TensorProd(x, TensorProd(y, fi), z)), InSet(i, Interval(two, four))))
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\{\left(x {\otimes} y {\otimes} f\left(i\right) {\otimes} z\right) = \left(x {\otimes} \left(y {\otimes} f\left(i\right)\right) {\otimes} z\right) \textrm{ if } i \in \{2~\ldotp \ldotp~4\}\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameter: 26
body: 1
1Conditionalvalue: 2
condition: 3
2Operationoperator: 4
operands: 5
3Operationoperator: 6
operands: 7
4Literal
5ExprTuple8, 9
6Literal
7ExprTuple26, 10
8Operationoperator: 20
operands: 11
9Operationoperator: 20
operands: 12
10Operationoperator: 13
operands: 14
11ExprTuple15, 22, 23, 17
12ExprTuple15, 16, 17
13Literal
14ExprTuple18, 19
15Variable
16Operationoperator: 20
operands: 21
17Variable
18Literal
19Literal
20Literal
21ExprTuple22, 23
22Variable
23Operationoperator: 24
operand: 26
24Variable
25ExprTuple26
26Variable