Emacs Org Mode Snippets Emacs org mode like Jupyter

# Images
#+CAPTION: This is the caption for the next figure link (or table)
#+NAME:   fig:SED-HR4049
[[./img/a.jpg]]

# Image with custom width
#+attr_html:  :width 1000px
#+attr_org:  :width 1000
[[~/images/examples.jpg]]

# Link to a specific section in an org mode document called Golang Tutorial
[[file:005-Golang.org::*Golang Tutorial][Golang Tutorial]]

# Footnotes
The Org website [fn:50] now looks a lot better than it used to.
[fn:50] The link is: https://orgmode.org

# Specify file variables in first line of file
# https://www.gnu.org/software/emacs/manual/html_node/emacs/Specifying-File-Variables.html
,# -*- org-image-actual-width: nil; org-imenu-depth: 5 -*-

# Turn on inline images in Org Mode anywhere in buffer
# https://orgmode.org/manual/In_002dbuffer-Settings.html
,,#+STARTUP: inlineimages

# Run a specific program using :shebang
# https://orgmode.org/worg/org-contrib/babel/languages/ob-doc-shell.html
#+begin_src sh :shebang #!/home/justin/.nix-profile/bin/nu :results output
ls
#+end_src

# Python session like Jupyter Note books
# Source: https://rgoswami.me/posts/jupyter-orgmode/
# Set the environment Python binary in the properties for the file
# Specific at section heading
#+PROPERTY: header-args:python :python /home/user/Code/myproject/.venv/bin/python :session One :results output :exports both
#+title: Emacs org mode like Jupyter
* Python Session

# or properties block in a section heading
,:PROPERTIES:
,:header-args:    :python /home/user/Code/myproject/.venv/bin/python :session One :results output file :exports both
,:END:

# Use Python like normal, note =:results output file :exports both= are required for
# either python source blocks or in the header arguments
#+begin_src python :results output file :exports both

import matplotlib.pyplot as plt

x = [1, 2, 3, 4]
y = [2, 4, 6, 8]

plt.plot(x, y)
plt.savefig('output.png')
# return filename to org-mode
print('output.png')
#+end_src

# Set Python command, such as a virtual environment to use
, #+begin_src emacs-lisp
(setq org-babel-python-command "/usr/bin/python3")
#+end_src

# Run Python code and show executable being used
#+begin_src python :results output
import sys
print(sys.executable)
print("Hello World")
#+end_src

# Output results as JSON or other code programming languages
#+begin_src sh :results output code :wrap src json
curl https://jsonplaceholder.typicode.com/todos/1
#+end_src

# Run a specific program using :shebang
# See https://orgmode.org/worg/org-contrib/babel/languages/ob-doc-shell.html
#+begin_src sh :shebang #!/home/justin/.nix-profile/bin/nu :results output raw
sys host
#+end_src

# Run SQL
# https://orgmode.org/worg//org-contrib/babel/languages/ob-doc-sql.html
#+begin_src sql :engine mysql
  DESCRIBE `some_table`;
#+end_src

The following sections shows babel examples and results in org-mode

Python execution

Python session like Jupyter Note books

Source: https://rgoswami.me/posts/jupyter-orgmode/

Set the environment Python binary in the properties for the file

Specific at section heading

,* Python Session

or properties block in a section heading

Running commands

Use Python like normal, note :results output file :exports both are required for either python source blocks or in the header arguments

import matplotlib.pyplot as plt

x = [1, 2, 3, 4]
y = [2, 4, 6, 8]

plt.plot(x, y)
plt.savefig('output.png')
# return filename to org-mode
print('output.png')

Set Python command, such as a virtual environment to use

(setq org-babel-python-command "/usr/bin/python3")

Run Python code and show executable being used

import sys
print(sys.executable)
print("Hello World")

Run a specific program using :shebang

See https://orgmode.org/worg/org-contrib/babel/languages/ob-doc-shell.html

This method can be used to run any command, programming language and get its output with a specific path or in the user’s PATH environment variable

sys host

Run shells available on path

ps | where name =~ 'emacs'

Using !shebang with Racket, Python, and Deno examples

#lang racket/base
(+ 1 1)

print("Hello from Python!")

import * as R from "npm:ramda"

R.forEach( (i) => console.log(i), [1, 2, 3, 4])

Output results as JSON or other code programming languages

curl https://jsonplaceholder.typicode.com/todos/1

Using hurl for API testing, see Org-mode and Hurl, requires hurl-mode or run commands using :shebang or regular shell

GET https://swapi.dev/api/people/1/

HTTP/2 200

Using hurl for passing variables

GET {{hostname}}/api/people/1

PlantUML

Activate inlineimages in org-mode and output image file and adjust width for better viewing

@startuml
class Animal {
  +String name
}

class Dog {
  +bark()
}


Animal <|-- Dog
@enduml

See more examples at PlantUML Snippets - PlantUML Snippets

SQL

Source: SQL Source Code Blocks in Org Mode with examples from Ryan Prior / Emacs Org Data Starter · GitLab

Make sure the corresponding sql binary is installed on the system like sqlite3, psql, and others

DESCRIBE `some_table`;

Run R for SQL query

library(RMySQL)
con <- dbConnect(MySQL(), user="user", password="pwd", dbname="dbname", host="host")
q <-
<<quote-blks("my-query")>>
c <- dbGetQuery(con, q)
dbDisconnect(con)
c

Another option is the query could be set up to run on its own

SELECT * FROM mytable
WHERE id > 500

MySQL

Connecting & running a basic query

Follow the MySQL instructions in the org-babel documentation. This example uses source block level properties.
```
SHOW TABLES;
```
Loading data & running queries

Uses subheader properties for the configuration instead of putting the configuration on every block. Use the source block level for one off qureies.
1. Create a database
```
create database if not exists org_test;
```

PostgreSQL

Connecting & running a basic query

Follow the PostgresQL instructions in the org-babel documentation
```
\list
```

Loading data & running queries using heading properties

Create a database

select 'CREATE DATABASE org_test' where not exists (SELECT FROM pg_database WHERE datname = 'org_test')\gexec

SQLite

Follow the ob-sqlite instructions in the org-babel documentation

select sqlite_version();

select * from greeting;

Loading data & running queries at heading level

Creating a new table & inserting some data

CREATE TABLE IF NOT EXISTS org_resources (
  id INT,
  resource TEXT,
  url TEXT
  );