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I wanted to share a function that I’ve found incredibly useful while conducting qualitative data analysis of interviews. During this type of research, structuring my interview data and maintaining a clear overview is crucial. To assist with this, I’ve developed a function in Emacs Lisp that uses tags to extract specific headlines into a new buffer.

This function, extract-headlines-by-tag, prompts the user to enter a tag. The function then scans the entire buffer, and for each headline that contains the specified tag, it extracts not only the headline but also its content. These extracted parts are then transferred into a new buffer. I’ve made the new buffer pop up for immediate review after the extraction process.

Here’s the piece of code:

(defun extract-headlines-by-tag (tag)
  "Extract headlines and their content from current buffer by TAG."
  (interactive "sEnter tag: ")
  (save-excursion
    (let ((result-buffer (generate-new-buffer (concat "/Extracted Headlines " tag "*"))))
      (with-current-buffer result-buffer
        (org-mode)
        (insert "* Extracted Headlines by Tag: " tag " *\n\n"))
      (org-element-map (org-element-parse-buffer) 'headline
        (lambda (headline)
          (when (member tag (org-element-property :tags headline))
            (with-current-buffer result-buffer
              (insert (org-element-interpret-data headline) "\n")))))
      (pop-to-buffer result-buffer))))

#emacs #elisp #lisp

Just wanted to show you how to use org tables with custom elisp functions, in case you dont know its possible:

The following table shows results from a questionnaire:

#+name: sus-questionnaire-results
#+caption: SUS Questionnaire Results
#+attr_latex: :align l|r|r|r|r|r|r|r|r|r|r|l  :font \fontspec{Noto Sans Condensed Light}
| USER | Q1 | Q2 | Q3 | Q4 | Q5 | Q6 | Q7 | Q8 | Q9 | Q10 |  SUS |
|------+----+----+----+----+----+----+----+----+----+-----+------|
| U1   |  5 |  2 |  2 |  1 |  3 |  4 |  3 |  2 |  1 |   1 | 60.0 |
| U2   |  5 |  2 |  4 |  2 |  5 |  1 |  4 |  1 |  4 |   1 | 87.5 |
| U3   |  5 |  2 |  4 |  1 |  4 |  2 |  4 |  1 |  4 |   3 | 80.0 |
#+tblfm: $12='(ux:sus-calc-score-per-row '($2..$11));N

The SUS column is calculated for each row using the values from column 2 to 11. When the ‘N’ flag is used, all referenced elements are parsed as numbers and interpolated as Lisp numbers

Here is the elisp function:

(defun ux:sus-calc-score (lst)
  (let ((counter 0))
    (mapcar (lambda (x)
              (setq counter (1+ counter))
              (if (= 0 (% counter 2))
                  (- 5 x)
                (1- x)))
            lst)))

(defun ux:sus-calc-score-per-row (lst)
  (* (apply '+ (ux:sus-calc-score lst)) 2.5))

Thats all!

Standard Unix tools that are interpreters follow a common command line protocol that is necessary to work with “shebang scripts”. SBCL doesn’t do this by default, but adding the following snippet to an initialization file does the trick:

;; content of ~/.sbclrc

;;; If the first user-processable command-line argument is a filename,
;;; disable the debugger, load the file handling shebang-line and quit.
(let ((script (and (second *posix-argv*)
                   (probe-file (second *posix-argv*)))))
  (when script
    ;; Handle shebang-line
    (set-dispatch-macro-character #\# #\!
                                  (lambda (stream char arg)
                                    (declare (ignore char arg))
                                    (read-line stream)))
    ;; Disable debugger
    (setf *invoke-debugger-hook*
          (lambda (condition hook)
            (declare (ignore hook))
            ;; Uncomment to get backtraces on errors
            ;; (sb-debug:backtrace 20)
            (format *error-output* "Error: ~A~%" condition)
            (quit)))
    (load script)
    (quit)))

#!/usr/local/bin/sbcl --noinform
(write-line "Hello, World!")

Hey #Emacs enthusiasts! I’ve been working on optimizing my #OrgMode capture templates, and I thought I’d share what I’ve come up with.

The goal is to make note-taking and task management more interconnected and context-aware. I wanted to automatically link notes to tasks I’m currently working on, or manually link them if no task is clocked in.

This function checks if a task is clocked in. If yes, it grabs the ID and heading of that task and formats it into an Org link. If no task is clocked in, it prompts for a manual ID.

(defun mk/link-to-current-task ()
  "Return an Org link to the current clocked-in task, if any, or prompt for manual entry."
  (if (org-clock-is-active)
      (with-current-buffer (marker-buffer org-clock-marker)
        (save-excursion
          (goto-char org-clock-marker)
          (format ":TASK_ID: [[id:%s][%s]]"
                  (org-id-get)
                  (org-get-heading t t))))
    (let ((manual-id (read-string "Enter Task ID (leave empty if not applicable): ")))
      (unless (string-empty-p manual-id)
        (format ":TASK_ID: [[id:%s][Manual Task]]" manual-id)))))

This template captures a note and uses the above function to populate a :TASK_ID: property, linking the note to a task.

(add-to-list 'org-capture-templates
             `("n" "Note" entry (file+headline "agenda/notes.org" "Notes")
               ,(concat "* %? :NOTE:\n"
                        ":PROPERTIES:\n"
                        "%(mk/link-to-current-task)\n"
                        ":END:\n"
                        "%i\n%a\n"
                        "Entered on: %U\n")))

This template automatically generates an :ID: property when capturing a new task.

(add-to-list 'org-capture-templates
             `("t" "Task" entry (file "agenda/tasks.org")
                   ,(format "* TODO %%? :TASK:\n:PROPERTIES:\n:ID: %s\n:END:\nEntered on %%U\n%%a"
                            (org-id-new))))

Hope you find this useful! Feedback and improvements are always welcome. #EmacsLife #Productivity

[2023-02-25 Sat] Use hunspell instead of aspell as background service for spell checking. Why? because hunspell allows you to use more than one dictionary at the same time.

[2023-01-30 Mon] If you are using ox-rss to export an RSS file from org, and want to use custom urls and not the reference number generate by org. You need to set a :CUSTOM_ID property for every headline. Change the code in ox-rss.el on line 247:

(anchor (org-export-get-reference headline info))

to the following code:

(anchor
 (or (org-element-property :CUSTOM_ID headline)
     (org-export-get-reference headline info)))

[2023-01-29 Sun] If you are like me, and have more than one PC or smartphone, you need to share important files between these devices. I was looking for an private cloud which respects the EU GDPR. I found a excelent service provided by Hetzner, the Storage Share.