The trillions of bacteria in and on our bodies can bolster our
health and contribute to
disease,
but just which microbes are the key actors has been elusive. Now, a
study involving thousands of people in Finland has identified a
potential microbial culprit in some cases of depression.
The finding, which emerged from a study of how genetics and diet
affect the microbiome, “is really solid proof that this association
could have major clinical importance,” says Jack Gilbert, a
microbial ecologist at the University of California, San Diego, who
was not involved with the work.
As software developers, we’ve all come across those annoying,
not-so-useful error messages when using some library or framework:
"Couldn’t parse config file", "Lacking permission for this
operation", etc. Ok, ok, so something went wrong apparently; but
what exactly? What config file? Which permissions? And what should
you do about it? Error messages lacking this kind of information
quickly create a feeling of frustration and helplessness.
So what makes a good error message then? To me, it boils down to
three pieces of information which should be conveyed by an error
message:
Context: What led to the error? What was the code trying to do
when it failed?
The error itself: What exactly failed?
Mitigation: What needs to be done in order to overcome the error?
One of the most basic analysis functions is grouping and aggregating
data. In some cases, this level of analysis may be sufficient to
answer business questions. In other instances, this activity might
be the first step in a more complex data science analysis. In
pandas, the groupby function can be combined with one or more
aggregation functions to quickly and easily summarize data. This
concept is deceptively simple and most new pandas users will
understand this concept. However, they might be surprised at how
useful complex aggregation functions can be for supporting
sophisticated analysis.
This article will quickly summarize the basic pandas aggregation
functions and show examples of more complex custom
aggregations. Whether you are a new or more experienced pandas user,
I think you will learn a few things from this article.
This article is a tutorial that’s meant to cover Python packages,
modules, and import statements in enough depth for a beginner to
intermediate Python developer. The goal is to answer common
questions people have about these topics. We also will strive to
explain everything clearly and step by step, to show you errors you
might see along the way and how to solve them, and to illustrate how
things work with simple examples.
Pete and Debbie are both about to turn 40, their kids hate each
other, both of their businesses are failing, they're on the verge of
losing their house, and their relationship is threatening to fall
apart.
In the evening we watched This Is
40. I liked the movie a little
so I give it a 6 out of 10. I did like it that a part of Debaser by
the band Pixies was played and that there was a Pixies poster in
the office of one of the main characters. And Alice liked that Billie
Joe Armstrong of the band Green Day was in the movie.
In this article, I will implement the basic CIDR routing table in
Rust, optimize the routing algorithm, and benchmark different
solutions for comparison.
It has many good features, which are probably why it is used:
snapshots (with send/receive suppport), checksumming, RAID of some
kind (with scrubbing support), deduplication, compression, and
encryption.
But ZFS also has a lot of downsides. It is not the only way to
achieve those features on Linux, and there are better alternatives.
I recently sped up GoAWK by switching from a tree-walking
interpreter to a bytecode compiler with a virtual machine
interpreter. I discuss why it’s faster and how the new interpreter
works.
For every web app I work on, a database client is always present for
exploring data and building complex queries. Recently, I have moved
on from my PgAdmin to org-mode for this purpose, because why not.
In order to better understand how the garbage collector works, I
decided to trace its low-level behavior on a live application. In
this investigation, I'll instrument the Go garbage collector with
eBPF uprobes.
The inetd ‘super-server’ is a special application which ties
incoming network connections to locally-run commands. Using a
single super-server to handle all network requests conserves
memory and CPU resources at the expense of increased application
latency. Although inetd has largely fallen out of fashion today, it
was the most common method for handling network requests in the
early days of the Internet.
In this post, I want to explain how DNS resolvers work in a
different way – with a short Go program that does the same thing
described in the comic. The main function (resolve) is actually
just 20 lines, including comments.
Postgres supports three types for "schemaless" data:
JSON (added
in 9.2),
JSONB
(added in 9.4), and
HSTORE (added in
8.2 as an extension). Unfortunately, the performance of queries of
all three gets substantially slower (2-10×) for values larger than
about 2 kiB, due to how Postgres stores long variable-length data
(TOAST). The
same performance cliff applies to any variable-length types, like
TEXT
and
BYTEA. This
article contains some quick-and-dirty benchmark results to explore
how Postgres's performance changes for the "schemaless" data types
when they become large. My conclusion is that you should expect a
2-10× slower queries once a row gets larger than Postgres's 2 kiB
limit.
grep is one of the most universal and commonly-used commands on
the command line. I count about 50 flags you can use on it in my man
page. So which ones are the ones you should know about for everyday
use?
If you’ve been around Haskell circles for a bit, you’ve probably
seen the term “free monads”. This article aims to introduce free
monads and explain why they are useful.
To whet your appetite a little, free monads are basically a way to
easily get a generic pure Monad instance for any Functor. This can
be rather useful in many cases when you’re dealing with tree-like
structures, but to name a few:
To build an AST for an eDSL using do-notation.
To have different semantics for the same monad in different
contexts, e.g., define an interpreter and a pretty-printer for an
eDSL, or have a mock interpreter in addition to a real one.
To build a decision-tree type structure harnessing the do-notation
for non-determinism (like with lists, but for trees).
I originally wrote this at work, after my team spent far too many
days yelling at the computer because of
Mojibake. Thanks to my
employer for allowing me to publish it, and the several colleagues
who provided helpful feedback. Any errors are, naturally, not their
fault.
Python developers trust their applications to have a solid security
state due to the use of standard libraries and common
frameworks. However, within Python, just like in any other
programming language, there are certain features that can be
misleading or misused by developers. Often it is only a very minor
subtlety or detail that can make developers slip and add a severe
security vulnerability to the code base.
In this blog post, we share 10 security pitfalls we encountered in
real-world Python projects. We chose pitfalls that we believe are
less known in the developer community. By explaining each issue and
its impact we hope to raise awareness and sharpen your security
mindset. If you are using any of these features, make sure to check
your Python code!
One of the things people often complain about when doing Async Rust
is cancellation. This has always been a bit confusing to me, because
it seems to me that async cancellation should feel a lot like panics
in practice, and people don’t complain about panics very often
(though they do sometimes). This post is the start of a short series
comparing panics and cancellation, seeking after the answer to the
question “Why is async cancellation a pain point and what should we
do about it?” This post focuses on explaining Rust’s panic
philosophy and explaining why I see panics and cancellation as
being quite analogous to one another.