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Expression of type Conditional

from the theory of proveit.trigonometry

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, a, b
from proveit.logic import And, Equals, InSet
from proveit.numbers import Abs, Exp, Mult, Real, e, frac, i, subtract, two
from proveit.trigonometry import Sin
In [2]:
# build up the expression from sub-expressions
expr = Conditional(Equals(Abs(subtract(Exp(e, Mult(i, a)), Exp(e, Mult(i, b)))), Mult(two, Sin(frac(Abs(subtract(a, b)), two)))), And(InSet(a, Real), InSet(b, Real)))
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\{\left|\mathsf{e}^{\mathsf{i} \cdot a} - \mathsf{e}^{\mathsf{i} \cdot b}\right| = \left(2 \cdot \sin{\frac{\left|a - b\right|}{2}}\right) \textrm{ if } a \in \mathbb{R} ,  b \in \mathbb{R}\right..
In [5]:
stored_expr.style_options()
namedescriptiondefaultcurrent valuerelated methods
condition_delimiter'comma' or 'and'commacomma('with_comma_delimiter', 'with_conjunction_delimiter')
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Conditionalvalue: 1
condition: 2
1Operationoperator: 3
operands: 4
2Operationoperator: 5
operands: 6
3Literal
4ExprTuple7, 8
5Literal
6ExprTuple9, 10
7Operationoperator: 36
operand: 16
8Operationoperator: 41
operands: 12
9Operationoperator: 14
operands: 13
10Operationoperator: 14
operands: 15
11ExprTuple16
12ExprTuple32, 17
13ExprTuple46, 18
14Literal
15ExprTuple50, 18
16Operationoperator: 43
operands: 19
17Operationoperator: 20
operand: 24
18Literal
19ExprTuple22, 23
20Literal
21ExprTuple24
22Operationoperator: 34
operands: 25
23Operationoperator: 48
operand: 30
24Operationoperator: 27
operands: 28
25ExprTuple38, 29
26ExprTuple30
27Literal
28ExprTuple31, 32
29Operationoperator: 41
operands: 33
30Operationoperator: 34
operands: 35
31Operationoperator: 36
operand: 40
32Literal
33ExprTuple45, 46
34Literal
35ExprTuple38, 39
36Literal
37ExprTuple40
38Literal
39Operationoperator: 41
operands: 42
40Operationoperator: 43
operands: 44
41Literal
42ExprTuple45, 50
43Literal
44ExprTuple46, 47
45Literal
46Variable
47Operationoperator: 48
operand: 50
48Literal
49ExprTuple50
50Variable