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Expression of type Lambda

from the theory of proveit.numbers.summation

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, a, k
from proveit.logic import InSet
from proveit.numbers import Interval, seven, subtract, two
In [2]:
# build up the expression from sub-expressions
expr = Lambda(k, Conditional(subtract(k, two), InSet(k, Interval(a, seven))))
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())
k \mapsto \left\{k - 2 \textrm{ if } k \in \{a~\ldotp \ldotp~7\}\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameter: 10
body: 2
1ExprTuple10
2Conditionalvalue: 3
condition: 4
3Operationoperator: 5
operands: 6
4Operationoperator: 7
operands: 8
5Literal
6ExprTuple10, 9
7Literal
8ExprTuple10, 11
9Operationoperator: 12
operand: 16
10Variable
11Operationoperator: 14
operands: 15
12Literal
13ExprTuple16
14Literal
15ExprTuple17, 18
16Literal
17Variable
18Literal