logo

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, m, x
from proveit.logic import And, Equals, InSet
from proveit.numbers import Abs, Complex, Exp, Interval, Less, Sum, frac, infinity, one, subtract, zero
In [2]:
# build up the expression from sub-expressions
expr = Lambda(x, Conditional(Equals(Sum(index_or_indices = [m], summand = Exp(x, m), domain = Interval(zero, infinity)), frac(one, subtract(one, x))), And(InSet(x, Complex), Less(Abs(x), one))))
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())
x \mapsto \left\{\left(\sum_{m = 0}^{\infty} x^{m}\right) = \frac{1}{1 - x} \textrm{ if } x \in \mathbb{C} ,  \left|x\right| < 1\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameter: 40
body: 1
1Conditionalvalue: 2
condition: 3
2Operationoperator: 4
operands: 5
3Operationoperator: 6
operands: 7
4Literal
5ExprTuple8, 9
6Literal
7ExprTuple10, 11
8Operationoperator: 12
operand: 19
9Operationoperator: 14
operands: 15
10Operationoperator: 34
operands: 16
11Operationoperator: 17
operands: 18
12Literal
13ExprTuple19
14Literal
15ExprTuple30, 20
16ExprTuple40, 21
17Literal
18ExprTuple22, 30
19Lambdaparameter: 38
body: 24
20Operationoperator: 25
operands: 26
21Literal
22Operationoperator: 27
operand: 40
23ExprTuple38
24Conditionalvalue: 28
condition: 29
25Literal
26ExprTuple30, 31
27Literal
28Operationoperator: 32
operands: 33
29Operationoperator: 34
operands: 35
30Literal
31Operationoperator: 36
operand: 40
32Literal
33ExprTuple40, 38
34Literal
35ExprTuple38, 39
36Literal
37ExprTuple40
38Variable
39Operationoperator: 41
operands: 42
40Variable
41Literal
42ExprTuple43, 44
43Literal
44Literal