Useful Bash Commands

How many lines with a given extension?

find . -name "*.$1" | xargs wc -l| tail -n 1

To run this site locally

sudo gem install rails
sudo gem install jekyll
sudo gem install jekyll bundler
cd ~/desiredFolder

bundle init
bundle install
bundle add jekyll
bundle exec jekyll serve

To turn .enex notes from Evernote into .md files directly: evernote2md

To find all files containing a given expression. grep -rnw '/path/to/somewhere/' -e 'pattern'

Tar commands:

To extract a tarfile:

tar -xzf myfile.tar.gz

x for extract, z for zip, f for file. -v for verbose, is optional.

tar -czf new_name.tar.gz source_directory

c for create, z for zip, v for verbose (optional) and f for file.

Note that source comes after destination, like in a ASM instruction!

Basic sed use case

echo 'this-is-a-path' | sed 's/-/\//g' output: this/is/a/path

Redshift copy from S3

copy $TABLE\_NAME
from 'S3\_PATH'
iam\_role '$iam\_role'
removequotes
emptyasnull
blanksasnull
maxerror 100
delimiter ','
IGNOREHEADER 1
; 

Watch example: watch -n 10 ls -lAhF

Classic nvidia commands:

• nvcc –version : get CUDA version
• nvidia-smi : display cute table with stats that include VRAM.

python reindex after sorting panads dataframe:

limit_df.sort_values(['case', 'limit'],inplace = True)
limit_df.reset_index(drop=True, inplace = True)

Image compression with optimizt

npm i -g @funboxteam/optimizt
find . -iname \*.png -exec optimizt --lossless {} +

To find a book if it’s on the public domain, easily look for it on archive.org with this google search:

site:archive.org intitle:full/text/of intext:Lovecraft

Values for rel attribute in anchor tags.

• rel=”noopener” you use on all links opening in new tabs using the target _blank. There are security implications if you don’t use the noopener value on your links opening in new tabs. A malicious attacker can use the window.opener object to change the content and location of the originating page.
• rel=”noreferrer” can serve a similar purpose as the noopener, especially in older browsers. Hence, it makes sense to use them both. Additionally, noreferrer can affect your analytics and report traffic as direct instead of referral.
• rel=”nofollow” will inform search engines not to pass the link juice to the linked page, and it will not pass PageRank. You can consider it as a value that is used when you want to link to another page but without “endorsing” it. It is the only rel value with a tangible effect on SEO efforts.

Get all <p> from a site

To remove all ads and similar stuff and then get the cleaner text possible

document.querySelectorAll('iframe').forEach(iframe => iframe.remove());
document.querySelectorAll('img').forEach(iframe => iframe.remove());
document.querySelectorAll('ins').forEach(iframe => iframe.remove());
res = ''
document.querySelectorAll('p').forEach(p => res+=('<p>'+p.innerHTML + '</p>'));
res = res.replaceAll('\x3Cscript>(adsbygoogle = window.adsbygoogle || []).push({});\x3C/script>','');
res += '<style>
html {
  max-width: 70ch;
  padding: 3em 1em;
  margin: auto;
  line-height: 1.75;
  font-size: 1.25em;
}
</style>'

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04 Nov 2020 - importance: 3