Expression of type Lambda

from the theory of proveit.linear_algebra

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, IndexedVar, Lambda, i, x, y
from proveit.linear_algebra import TensorProd
from proveit.logic import InSet
from proveit.numbers import Interval, nine, one

# build up the expression from sub-expressions
expr = Lambda(i, Conditional(TensorProd(x, IndexedVar(y, i)), InSet(i, Interval(one, nine))))

expr:

# 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

# Show the LaTeX representation of the expression for convenience if you need it.
print(stored_expr.latex())

i \mapsto \left\{x {\otimes} y_{i} \textrm{ if } i \in \{1~\ldotp \ldotp~9\}\right..

stored_expr.style_options()

no style options

# display the expression information
stored_expr.expr_info()

	core type	sub-expressions	expression
0	Lambda	parameter: 15 body: 1
1	Conditional	value: 2 condition: 3
2	Operation	operator: 4 operands: 5
3	Operation	operator: 6 operands: 7
4	Literal
5	ExprTuple	8, 9
6	Literal
7	ExprTuple	15, 10
8	Variable
9	IndexedVar	variable: 11 index: 15
10	Operation	operator: 13 operands: 14
11	Variable
12	ExprTuple	15
13	Literal
14	ExprTuple	16, 17
15	Variable
16	Literal
17	Literal