<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Notes | Mahdi Kooshkbaghi</title><link>https://mahdikooshkbaghi.gitlab.io/tag/notes/</link><atom:link href="https://mahdikooshkbaghi.gitlab.io/tag/notes/index.xml" rel="self" type="application/rss+xml"/><description>Notes</description><generator>Wowchemy (https://wowchemy.com)</generator><language>en-us</language><lastBuildDate>Tue, 11 Aug 2026 00:00:00 +0000</lastBuildDate><image><url>https://mahdikooshkbaghi.gitlab.io/media/icon_hu_1ab110491474e3b8.png</url><title>Notes</title><link>https://mahdikooshkbaghi.gitlab.io/tag/notes/</link></image><item><title>A Small Clockwork for Uncertain Things</title><link>https://mahdikooshkbaghi.gitlab.io/post/a-small-clockwork/</link><pubDate>Tue, 11 Aug 2026 00:00:00 +0000</pubDate><guid>https://mahdikooshkbaghi.gitlab.io/post/a-small-clockwork/</guid><description>&lt;p&gt;This is a placeholder for a longer note. Suppose a small mechanism turns noisy
observations into a useful signal, provided we resist the urge to make it sound
more certain than it is.&lt;/p&gt;
&lt;p&gt;
&lt;figure &gt;
&lt;div class="d-flex justify-content-center"&gt;
&lt;div class="w-100" &gt;&lt;img alt="An abstract clockwork sketch"
src="https://mahdikooshkbaghi.gitlab.io/post/a-small-clockwork/diagram.svg"
loading="lazy" data-zoomable /&gt;&lt;/div&gt;
&lt;/div&gt;&lt;/figure&gt;
&lt;/p&gt;
&lt;p&gt;The objective can be written in ordinary display math:&lt;/p&gt;
&lt;p&gt;$$
\mathcal{L}(\theta) = \frac{1}{n}\sum_{i=1}^{n}\left(y_i - f_\theta(x_i)\right)^2 + \lambda \lVert\theta\rVert_2^2.
$$&lt;/p&gt;
&lt;p&gt;And a small executable thought can live alongside the prose:&lt;/p&gt;
&lt;pre&gt;&lt;code class="language-python"&gt;def damped_update(value, gradient, step_size=0.1):
return value - step_size * gradient / (1.0 + abs(gradient))
&lt;/code&gt;&lt;/pre&gt;
&lt;p&gt;The final version can replace this text with an argument, a result, or a question
worth keeping open.&lt;/p&gt;</description></item><item><title>The Quiet Derivative</title><link>https://mahdikooshkbaghi.gitlab.io/post/the-quiet-derivative/</link><pubDate>Tue, 04 Aug 2026 00:00:00 +0000</pubDate><guid>https://mahdikooshkbaghi.gitlab.io/post/the-quiet-derivative/</guid><description>&lt;p&gt;Another temporary writing, placed here to establish the shape of the section.
The premise is simple: local behavior can be revealing without pretending to
explain the entire system.&lt;/p&gt;
&lt;p&gt;
&lt;figure &gt;
&lt;div class="d-flex justify-content-center"&gt;
&lt;div class="w-100" &gt;&lt;img alt="A contour-like field"
src="https://mahdikooshkbaghi.gitlab.io/post/the-quiet-derivative/diagram.svg"
loading="lazy" data-zoomable /&gt;&lt;/div&gt;
&lt;/div&gt;&lt;/figure&gt;
&lt;/p&gt;
&lt;p&gt;For a scalar field $g$, the local change in a direction $v$ is&lt;/p&gt;
&lt;p&gt;$$
D_v g(x) = \nabla g(x)^\mathsf{T}v.
$$&lt;/p&gt;
&lt;pre&gt;&lt;code class="language-python"&gt;import numpy as np
def directional_change(gradient, direction):
return float(np.dot(gradient, direction))
&lt;/code&gt;&lt;/pre&gt;
&lt;p&gt;This entry is intentionally placeholder prose. It can grow into a technical
essay, a short research note, or a notebook-backed explanation.&lt;/p&gt;</description></item></channel></rss>