<p>Usually in CNF you want to learn a vector field network <span class="math-container">$\mathcal{v^t(x)}$</span>, which with some abuse of notation, can be red as <span class="math-container">$\mathcal{v(x|t)}$</span>, so wither you create a network for each time (pretty expensive), or you hope that a network can learn the time-conditional vector field, thus you feed the net the time, so that it knows which vector field you want</p>

CC BY-SA 4.0
2024-08-15T13:54:22.990Z
2024-08-15T13:54:22.990Z
Alberto
<p>I was going through the flow matching paper by Lipmann and others. I understood the paper fairly well. I was also looking at the code for the same over <a href="https://github.com/jmtomczak/intro_dgm/blob/main/sbgms/fm_example.ipynb" rel="nofollow noreferrer">here</a>. One thing I did not understand in the code is the computation of a time embedding to compute the velocity field. Why is it necessary to incorporate a time embedding?</p>

CC BY-SA 4.0
2024-08-14T19:13:41.533Z
you want xt=xt-1+f(xt-1), thus you need to tell the net the “t” term
Alberto
CC BY-SA 4.0
2024-08-15T12:54:57.607Z
Thank you, this clears it up for me. I missed this for some reason. You can type this up as the answer, and I will be happy to mark it as accepted.
pseudomonas
<neural-networks><generative-model>
Role of time embedding in flow matching
pseudomonas
# Role of time embedding in flow matching

(Asked by: username_0 on 2024-08-14)

I was going through the flow matching paper by Lipmann and others. I understood the paper fairly well. I was also looking at the code for the same over [here](https://github.com/jmtomczak/intro_dgm/blob/main/sbgms/fm_example.ipynb). One thing I did not understand in the code is the computation of a time embedding to compute the velocity field. Why is it necessary to incorporate a time embedding?

**Tags:** neural-networks, generative-model

> **Comments:**
> **username_1**: you want xt=xt-1+f(xt-1), thus you need to tell the net the “t” term  
> **username_0**: Thank you, this clears it up for me. I missed this for some reason. You can type this up as the answer, and I will be happy to mark it as accepted.  

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## 1 answers

### Answer by username_1 on 2024-08-15. Score: 2 | Accepted answer

Usually in CNF you want to learn a vector field network $\mathcal{v^t(x)}$, which with some abuse of notation, can be red as $\mathcal{v(x|t)}$, so wither you create a network for each time (pretty expensive), or you hope that a network can learn the time-conditional vector field, thus you feed the net the time, so that it knows which vector field you want


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