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## summation

### Re: summation

Hi

Just use Y(i-1,r,t). Note however, that this means that you can't use this for the first i if there is no value for i-1. If it is a variable, you probably will have to fix the Y(i-1) to a certain value or you can define the equation for all i > 1

Cheers

Renger

Just use Y(i-1,r,t). Note however, that this means that you can't use this for the first i if there is no value for i-1. If it is a variable, you probably will have to fix the Y(i-1) to a certain value or you can define the equation for all i > 1

Code: Select all

```
myeq(i,r)$(ord(i)>1)...
Y(i,r,t) =L= sum(t, Y(i-1,r,t);
```

Renger

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Enjoy modeling even more: Read my blog on modeling at The lazy economist

Enjoy modeling even more: Read my blog on modeling at The lazy economist