logo

Expression of type LessEq

from the theory of proveit.numbers.absolute_value

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 ExprRange, IndexedVar, Variable, a, b, c, n, x
from proveit.core_expr_types import x_1_to_n
from proveit.numbers import Abs, Add, LessEq, one
In [2]:
# build up the expression from sub-expressions
sub_expr1 = Variable("_a", latex_format = r"{_{-}a}")
expr = LessEq(Abs(Add(a, b, x_1_to_n, c)), Add(Abs(a), Abs(b), ExprRange(sub_expr1, Abs(IndexedVar(x, sub_expr1)), one, n), Abs(c)))
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|a + b+ x_{1} +  x_{2} +  \ldots +  x_{n} + c\right| \leq \left(\left|a\right| + \left|b\right|+ \left|x_{1}\right| +  \left|x_{2}\right| +  \ldots +  \left|x_{n}\right| + \left|c\right|\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: 12
operands: 6
5ExprTuple7
6ExprTuple8, 9, 10, 11
7Operationoperator: 12
operands: 13
8Operationoperator: 26
operand: 19
9Operationoperator: 26
operand: 20
10ExprRangelambda_map: 16
start_index: 24
end_index: 25
11Operationoperator: 26
operand: 22
12Literal
13ExprTuple19, 20, 18, 22
14ExprTuple19
15ExprTuple20
16Lambdaparameter: 31
body: 21
17ExprTuple22
18ExprRangelambda_map: 23
start_index: 24
end_index: 25
19Variable
20Variable
21Operationoperator: 26
operand: 28
22Variable
23Lambdaparameter: 31
body: 28
24Literal
25Variable
26Literal
27ExprTuple28
28IndexedVarvariable: 29
index: 31
29Variable
30ExprTuple31
31Variable