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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, beta, gamma, i
from proveit.logic import Equals, InSet
from proveit.numbers import Add, Interval, Mult, four, one, two
In [2]:
# build up the expression from sub-expressions
sub_expr1 = Mult(gamma, beta)
sub_expr2 = Add(i, one)
expr = Lambda(i, Conditional(Equals(Mult(sub_expr1, i, sub_expr2), Mult(sub_expr1, Mult(i, sub_expr2))), 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(\left(\gamma \cdot \beta\right) \cdot i \cdot \left(i + 1\right)\right) = \left(\left(\gamma \cdot \beta\right) \cdot \left(i \cdot \left(i + 1\right)\right)\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: 28
body: 2
1ExprTuple28
2Conditionalvalue: 3
condition: 4
3Operationoperator: 5
operands: 6
4Operationoperator: 7
operands: 8
5Literal
6ExprTuple9, 10
7Literal
8ExprTuple28, 11
9Operationoperator: 21
operands: 12
10Operationoperator: 21
operands: 13
11Operationoperator: 14
operands: 15
12ExprTuple16, 28, 25
13ExprTuple16, 17
14Literal
15ExprTuple18, 19
16Operationoperator: 21
operands: 20
17Operationoperator: 21
operands: 22
18Literal
19Literal
20ExprTuple23, 24
21Literal
22ExprTuple28, 25
23Variable
24Variable
25Operationoperator: 26
operands: 27
26Literal
27ExprTuple28, 29
28Variable
29Literal