a*******o 发帖数: 129 | 1 【 以下文字转载自 CS 讨论区,原文如下 】
发信人: ayiyahiho (sddddddddddddddddd), 信区: CS
标 题: lineariation problem....help, please
发信站: Unknown Space - 未名空间 (Mon Jun 6 17:52:27 2005) WWW-POST
Hi, all,
I have a nonlinear constraint which i don't know how to linearize it.
it is in the form
x*y=z
x and y both have a bound.
Then, how can i linearize it? I hope I can achieve a LP or MILP form by
linearization.
Thank you very much. | r****y 发帖数: 1437 | 2
log(x) + log(y) = log(z)
if negative numbers exist (e.g. x <0), just use -x to do all the stuff.
【在 a*******o 的大作中提到】 : 【 以下文字转载自 CS 讨论区,原文如下 】 : 发信人: ayiyahiho (sddddddddddddddddd), 信区: CS : 标 题: lineariation problem....help, please : 发信站: Unknown Space - 未名空间 (Mon Jun 6 17:52:27 2005) WWW-POST : Hi, all, : I have a nonlinear constraint which i don't know how to linearize it. : it is in the form : x*y=z : x and y both have a bound. : Then, how can i linearize it? I hope I can achieve a LP or MILP form by
| a*******o 发帖数: 129 | 3 Thank you very much.
I also have other constraints which x and y are linearized in them.
If I do log(x) and log(y), it would violate linearization of other
constraints.
I am sorry. I forgot to put on all the conditions.
Are there a way to use two or three inequalities to substitute this equality?
For example,
x*y=3.
Can I use like the following form to substitute it?
x+y>=C1
x-y<=C2...
x and y are continuous variable.
Thanks....I am not familiar with this kind of stuffs.
【在 r****y 的大作中提到】 : : log(x) + log(y) = log(z) : if negative numbers exist (e.g. x <0), just use -x to do all the stuff.
| h***o 发帖数: 26 | 4 google bilinear convex and concave envelope
【在 a*******o 的大作中提到】 : Thank you very much. : I also have other constraints which x and y are linearized in them. : If I do log(x) and log(y), it would violate linearization of other : constraints. : I am sorry. I forgot to put on all the conditions. : Are there a way to use two or three inequalities to substitute this equality? : For example, : x*y=3. : Can I use like the following form to substitute it? : x+y>=C1
| a*******o 发帖数: 129 | 5 Thanks a lot!
equality?
stuff.
【在 h***o 的大作中提到】 : google bilinear convex and concave envelope
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