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Expression of type Lambda

from the theory of proveit.linear_algebra.addition

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, Function, Lambda, i, v
from proveit.logic import InSet
from proveit.numbers import Interval, nine, one, subtract, two
In [2]:
# build up the expression from sub-expressions
expr = Lambda(i, Conditional(Function(v, [subtract(i, one)]), InSet(i, Interval(two, nine))))
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\{v\left(i - 1\right) \textrm{ if } i \in \{2~\ldotp \ldotp~9\}\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameter: 15
body: 2
1ExprTuple15
2Conditionalvalue: 3
condition: 4
3Operationoperator: 5
operand: 9
4Operationoperator: 7
operands: 8
5Variable
6ExprTuple9
7Literal
8ExprTuple15, 10
9Operationoperator: 11
operands: 12
10Operationoperator: 13
operands: 14
11Literal
12ExprTuple15, 16
13Literal
14ExprTuple17, 18
15Variable
16Operationoperator: 19
operand: 21
17Literal
18Literal
19Literal
20ExprTuple21
21Literal