sorokine/00-index.md

## 00-index.md

      
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              00-index.md
            
          
bash
tmux/byobu
git
iTerm2
Linux


neovim
Postgres
python
zsh


## bash.md

      
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              bash.md
            
          
    bash


ESC f - next word
ESC b - previous word
^w - delete previous word
^u - delete to line start
^y - paste deleted
ESC d - delete next word
ESC t - swap words
ESC r - restore line
ESC # - comment out line
ESC * - insert file names in CWD starting with
^x^e - invoke editor for the command
^_ - undo edit
: "${VAR:=default}" - set variable if not already set
redirection

>&2 echo error - echo to stderr
2>&1 - combine stdout and stderr
> >(tee stdout.log) 2> >(tee stderr.log) - redirect stdout and stderr to different files


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## git.md

      
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              git.md
            
          
    git


git worktree add <branch> <dir - create another directory with a branch
git restore <branchtag|sha> -- <file> - restore deleted file
git log --graph --all - show graph with all branches
git show development:my_file.txt - show file in another branch
git whatchanged -p my_file.rb - See What Has Changed on a File Over Time
git rev-list --all | xargs git grep -F '' - grep all branches
remove all untracked and ignored files and empty directories
git clean -fdX
find . -type d -empty -delete


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## iTerm2.md

      
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              iTerm2.md
            
          
    iTerm2


<Command> <Alt> <Mouse> - iTerm2 rectangular selection

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## Linux.md

      
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              Linux.md
            
          
    Linux


find . -mindepth 1 -maxdepth 1 -type d -print0 | xargs -0 du -sh | sort -h - list sizes of all directories including ones with spaces

-iname - is like -name but case insesitive


ping 0 - check if network is running on the localhost
use /usr/bin/time -v instead of time to get more detaiiled process infrmation
sort a file keeping header at the top: cat file | (read -r; printf "%s\n" "$REPLY"; sort)
sudo lshw - list hardware
pipe through pv to see the command progress
findmnt to see mount points with details

Ubuntu


fix for command-not-found on Ubuntu
sudo apt install --reinstall command-not-found
sudo chmod -R o+r /var/lib/command-not-found/

remote logout console session gnome-session-quit --no-prompt
adduser
sudo usermod -a -G <group> <user>; newgrp <group> add user to a group and reload assignment
xsel - copy/paste from/to clipboard

MacOS


⌘⇧. Command-Shift-. - show hidden files
⌘⇧G Commnad-Shift-G in file dialog - enter path

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## neovim.md

      
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              neovim.md
            
          
    neovim


gg/G - go to file start/end
556G - go to line 556
n/N - find next/previous
:map - show keybindings
reload file

:edit - current buffer
:checktime - all files


:r file - insert text from file
^w - window operations followed with

w - next window
v/s - vertical/horisontal split
o - minimize other windows
+/- - increase/decrease vertical size
</> - increase/decrease horisontal size
x - swap current window with the next
m - zoom/unzoom curren window
q - cancel window split
w - make all windows same size


:set scrollbind - sync scroll in windows
^v - start rectangular selection
:let mapleader - detect <Leader> key
^r - redo
find/replace

:%s/str/repl/gc - ask and replace
:%s/%Vstr/repl/g - search/replace within none-line selection


:set nowrap - prevent line wrapping
^y/^e/^u/^d - scroll up/down/pg up/pg down
gc, move - comment/uncomment, if does not work

comment block: in the 1st column ^v, select block, I # Esc
uncomment block: in the 1st column ^v, select block, d Esc


"ayy/"Ayy - copy/append selection to register a
zR/zM - open/close all folds
zo/zc open/close current fold
>/< indent/unindent block
>>/<< indent/unindent line
^r" insert register into command buffer
:so % - reload config while editing init.vim
F4 - ctags sidebar (:TagbarToggle)
F7 - run flake8
r - replace single character
% - jump to matching bracket
delete d/change c/yank y

di" - delete within quotes or other chracters
da" - delete within quotes and delete quotes
dtc - delete until chracter 'c'
df  - delete until next space or other chracter including it
dT  - delete backward until space or other character
daw - delete the whole word with space
diw - delte the whole word without space


quoting/unquoting

cs"' - change " to '
ds" - unquote "
ysiw" - quote word with "


^o/^i - jump to previos/next location (normal mode)
fc/Fc - jump forward/back to character c
gqip - wrap current line
:noh - remove search highlight
macro

qaq - start where 'a' is a regizter a-z
N@a - play macro in register 'a' 'N' number of times


^6 - switch to previous buffer
* - search for the word under cursor
marks

ma - mark position a
`a - jump to position a
'a - jump to line of position a
`. - jump to last edit


^ - move to 1st none-space character of the string
INSERT mode

^r* - insert yanked text
^o - perform a single command from NORMAL mode


r! date - insert current timestamp
gx - open browser on the current link
bw - completely close the file
:help - get help on a topic

^] - follow the link
^T - go back
^o/^i - history forward/back


:argdo/:bufdo/:windo/tabdo - run operation on multiple files
^l - redraw screen

git/fugitive


[/]c - jump prev/next hunk
,hs - stage current hunk
,hu - unstage current hunk
:G - start commit
ca in status window on commit -- amend

NERDTree


ma - create a file in the selected directory
:syntax on - fix weird symbols in the file list

DrawIt


,di - start line drawing mode
,ds - stop line drawing
<,>,^,v - arrows
^v, draw block

,b - draw a box
,l - create a box
,f - flood with character (does not work)


dbext


,sdt - describe table
,se - execute selection or statement under cursor
:DBCompleteTables - load table names for completion

Spellchecker & Thesaurus Query


:setlocal spell spelllang=en_us - start spellcheck
z= - spelling suggestions
zg - add misspelled word to local dictionary
]s/[s - move to next/previous misspelled word
,cs - on the word for list of synonyms, etc.

LatexBox


\lv - Latex view
\lt - Latex TOC
% - jump matching bracket
^X^O - complete

xml-plugin


% - jump between '<' and '>'
> - complete single line tag
>> - complete multiline tag
\x - surround selection with a tag
\% - jump to tag start
\d - delete surrounding tags
\c/\u - comment/uncomment selection

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## postgresqlpostgis.md

      
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              postgresqlpostgis.md
            
          
    PostgreSQL/PostGIS


fast count of rows estimate
SELECT reltuples::bigint AS estimate FROM pg_class WHERE relname = 'table_name';

poor man's histogram:
SELECT width_bucket(numeric_column, 1, 200, 20), count(*)
FROM table GROUP BY 1 ORDER BY 1

split_part('a:b', ':', 1) -> a
concat_ws(':', 'a', 'b', ..) - join strings with seprator
stop/kill query
SELECT * FROM pg_stat_activity WHERE state = 'active';
SELECT pg_cancel_backend(<pid of the process>)

convenient view for background queries
SELECT 
  now()-query_start as elapsed, 
  state, datname, pid, usename, 
  query, application_name, client_addr, 
  query_start, state_change, 
  wait_event_type, wait_event 
FROM pg_stat_activity WHERE state = 'active';


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## python.md

      
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              python.md
            
          
    Python


import ipdb; ipdb.set_trace() - drop into iPython
create virtual environment - https://docs.python.org/3/library/venv.html
python3 -m venv --upgrade-deps venv && \
. ./venv/bin/activate

install requirements
pip install -r requirements.txt

find all python environments in current directory and below
fd -p -g '**/bin/activate'

aList[::-1] - reverse a list
create conda environment:
conda create -n <env> python=3.12 pip 
conda activate <env>

useful decorators
@atexit.register
@dataclass
@unique
@singledispatch

clickable terminal links
import rich
rich.print("Hello [link=http://localhost:8000]App[/link]!")


Pandas


replace column names: df.columns = ['a', 'b', 'c']
insert top row
df.loc[-1] = [1,2,3]
df.index = df.index + 1
df = df.sort_index()

drop empty rows: df.dropna(axis='rows', inplace=True, how='all')

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## tmux.md

      
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              tmux.md
            
          
    tmux


^B I - Installs new plugins from GitHub or any other git repository
^B U - updates plugin(s)
^B alt u- remove/uninstall plugins not on the plugin list
^B [ - scroll/copy mode

q - quits
^<space> - start higlight
<esc>w - copy highlighted text


^B %/| - split vertical/horizontal
^B <-/^B -> - move between windows
^B z - zoom pane to the whole window
^B / - search
^B y - copy command to clipboard
^B Y - copy PWD to clipboard
^B C - create new session from within the currebt one
^B g - switch to another session
^B ] - paste from clipboard
^B b - last window
^B <space> - change layout
save buffer in file: ^B:capture-pane -S -3000<enter>^B:save-buffer file.txt<enter>
^B D - disconnect other clients
tmux new-session -A -s NAME - create new or attach to existing named session

byobu


byobu-tmux - start byobu with tmux CLI options
^B |/% - horizontal/vertical split
Enter - copy highlight

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## zsh.md

      
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              zsh.md
            
          
    zsh


[tab] - file name globs (requires setopt extendedglob)

<200-300> - range of integers
^*.c - negate glob
~ - exclude from pattern
**/* - get into subdir


=<command> - $(which <command>)
fc - run the editor on previous command
r a=b - rerun previous command with optional substitution
[ESC]q - put command on stack
[ESC]a - execute command keep it in buffer
[ESC]' - escape command

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