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i have this constraint right here, which is not linear. How would i linearize such a product. $number_t$ is a positive integer and $new_t$ and $reset_t$ are binary.

$$number_t = (number_{t-1}+new_t)\cdot (1-reset_t)$$

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Some comments already hinted at questions that give you the answer. In your specific example, this translates to the following:

\begin{align} 0 \leq number_t \leq (number_{t−1}+new_t) \newline number_t \geq (number_{t−1}+new_t)-reset_tM \newline number_t \leq M(1−reset_t) \end{align}

If $reset_t = 0$, through the first and second constraint we force $number_t$ to take value $number_{t-1}+new_t$. If $reset_t=1$, through the first and third constraint, we force $number_t$ to be 0. Where $M$ is a large enough number.

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  • $\begingroup$ Thank you @PeterD. Assuming i also have $number_t = (number_{t-1}+new_t)\cdot (1-reset_t)-c_t + b_t$, which of both are also binary, how would i need to modify the constraints then? Thanks in advance? $\endgroup$
    – Uni ewr
    Feb 13 at 14:38
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    $\begingroup$ Would it work if, for example, I replace $number_t$ with $nr_t$ in your solution and then calculate $number_t=nr_t-c_t+b_t$? $\endgroup$
    – Uni ewr
    Feb 13 at 15:17
  • $\begingroup$ @Uniewr yes that would work. $\endgroup$
    – PeterD
    Feb 13 at 19:29

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