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Expression of type Equals

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 a, b
from proveit.logic import Equals
from proveit.numbers import Abs, Exp, Mult, e, frac, i, subtract, two
from proveit.trigonometry import Sin
In [2]:
# build up the expression from sub-expressions
expr = Equals(Abs(subtract(Exp(e, Mult(i, a)), Exp(e, Mult(i, b)))), Mult(two, Sin(frac(Abs(subtract(a, b)), two))))
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|\mathsf{e}^{\mathsf{i} \cdot a} - \mathsf{e}^{\mathsf{i} \cdot b}\right| = \left(2 \cdot \sin{\frac{\left|a - b\right|}{2}}\right)
In [5]:
stored_expr.style_options()
namedescriptiondefaultcurrent valuerelated methods
operation'infix' or 'function' style formattinginfixinfix
wrap_positionsposition(s) at which wrapping is to occur; '2 n - 1' is after the nth operand, '2 n' is after the nth operation.()()('with_wrapping_at', 'with_wrap_before_operator', 'with_wrap_after_operator', 'without_wrapping', 'wrap_positions')
justificationif any wrap positions are set, justify to the 'left', 'center', or 'right'centercenter('with_justification',)
directionDirection of the relation (normal or reversed)normalnormal('with_direction_reversed', 'is_reversed')
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Operationoperator: 1
operands: 2
1Literal
2ExprTuple3, 4
3Operationoperator: 26
operand: 7
4Operationoperator: 31
operands: 6
5ExprTuple7
6ExprTuple22, 8
7Operationoperator: 33
operands: 9
8Operationoperator: 10
operand: 14
9ExprTuple12, 13
10Literal
11ExprTuple14
12Operationoperator: 24
operands: 15
13Operationoperator: 38
operand: 20
14Operationoperator: 17
operands: 18
15ExprTuple28, 19
16ExprTuple20
17Literal
18ExprTuple21, 22
19Operationoperator: 31
operands: 23
20Operationoperator: 24
operands: 25
21Operationoperator: 26
operand: 30
22Literal
23ExprTuple35, 36
24Literal
25ExprTuple28, 29
26Literal
27ExprTuple30
28Literal
29Operationoperator: 31
operands: 32
30Operationoperator: 33
operands: 34
31Literal
32ExprTuple35, 40
33Literal
34ExprTuple36, 37
35Literal
36Variable
37Operationoperator: 38
operand: 40
38Literal
39ExprTuple40
40Variable