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## JavaScript (Node.js), 68 bytes

```
f=(a)=>a.map((x)=>[...x.entries()].filter((e)=>e[1]).map((e)=>e[0]))
```

Run the function f on your input, e.g. `f([[1,0,1],[1,0,1],[0,1,0]])`.

The output looks like this:
```
[[0, 2], [0, 2], [1]]
```
with one subarray for each input subarray.

---

Explanation:
```
f=(a)=> // creates a function to run the input on
	a.map((x)=> // for each outer array:
		[...x.entries()]   // creates things like this: [index, value]
		.filter((e)=>e[1]) // keep ones where the value acts like true
		.map((e)=>e[0])    // return the indices for each one
	)