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Expression of type Lambda

from the theory of proveit.numbers.exponentiation

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, r, theta
from proveit.logic import And, Equals, InSet
from proveit.numbers import Exp, Integer, Mult, Real, e, frac, i, pi, two
In [2]:
# build up the expression from sub-expressions
expr = Lambda([r, theta], Conditional(Equals(Mult(r, Exp(e, Mult(i, theta))), r), And(InSet(r, Real), InSet(theta, Real), InSet(frac(theta, Mult(two, pi)), Integer))))
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())
\left(r, \theta\right) \mapsto \left\{\left(r \cdot \mathsf{e}^{\mathsf{i} \cdot \theta}\right) = r \textrm{ if } r \in \mathbb{R} ,  \theta \in \mathbb{R} ,  \frac{\theta}{2 \cdot \pi} \in \mathbb{Z}\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameters: 1
body: 2
1ExprTuple19, 34
2Conditionalvalue: 3
condition: 4
3Operationoperator: 5
operands: 6
4Operationoperator: 7
operands: 8
5Literal
6ExprTuple9, 19
7Literal
8ExprTuple10, 11, 12
9Operationoperator: 31
operands: 13
10Operationoperator: 16
operands: 14
11Operationoperator: 16
operands: 15
12Operationoperator: 16
operands: 17
13ExprTuple19, 18
14ExprTuple19, 20
15ExprTuple34, 20
16Literal
17ExprTuple21, 22
18Operationoperator: 23
operands: 24
19Variable
20Literal
21Operationoperator: 25
operands: 26
22Literal
23Literal
24ExprTuple27, 28
25Literal
26ExprTuple34, 29
27Literal
28Operationoperator: 31
operands: 30
29Operationoperator: 31
operands: 32
30ExprTuple33, 34
31Literal
32ExprTuple35, 36
33Literal
34Variable
35Literal
36Literal