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# System prepended metadata

title: week 3

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# week 3
## RNN
* At each time step, the memory cell takes the input value for that step.
* These steps will continue until we reach the end of our input dimension
* things such as closer numbers in the series might have a greater impact than those further away from our target value.

![](https://i.imgur.com/TsggzjN.png)



* The inputs are three dimensional.
* each timestamp, the memory cell input will be a four by one matrix, like this.
![](https://i.imgur.com/xuzergy.png)

## LSTM
* LSTMs are the cell state to this that keep a state throughout the life of the training so that the state is passed from cell to cell, timestamp to timestamp, and it can be better maintained. 
* In the case of texts, this was really powerful. 
![](https://i.imgur.com/MKBwVxz.png)
