Maxima Function
ratweight (x_1, w_1, ..., x_n, w_n)
ratweight()
Assigns a weight w_i to the variable x_i.
This causes a term to be replaced by 0 if its weight exceeds the
value of the variable ratwtlvl
(default yields no truncation).
The weight of a term is the sum of the products of the
weight of a variable in the term times its power.
For example, the weight of 3 x_1^2 x_2
is 2 w_1 + w_2
.
Truncation according to ratwtlvl
is carried out only when multiplying
or exponentiating canonical rational expressions (CRE).
ratweight ()
returns the cumulative list of weight assignments.
Note: The ratfac
and ratweight
schemes are incompatible and may not
both be used at the same time.
Examples:
(%i1) ratweight (a, 1, b, 1); (%o1) [a, 1, b, 1] (%i2) expr1: rat(a + b + 1)$ (%i3) expr1^2; 2 2 (%o3)/R/ b + (2 a + 2) b + a + 2 a + 1 (%i4) ratwtlvl: 1$ (%i5) expr1^2; (%o5)/R/ 2 b + 2 a + 1