How do I change the height of all text in an AutoCAD drawing at once?

What cadssistant does

1. Selects TEXT and MTEXT on the layer with one filter, or all of it if you don't name a layer.
2. Sets the height of each in a single AutoLISP pass. MTEXT keeps its wrap width; only the character height changes.
3. Replies with the count. "Only the ones that are 3.5" adds (40 . 3.5) to the filter; "scale by 0.7" multiplies instead of setting.

The same task in AutoLISP

(progn
  (setq ss (ssget "_X" '((0 . "TEXT,MTEXT") (8 . "A-ANNO"))) i 0)
  (if ss
    (repeat (sslength ss)
      (setq ed (entget (ssname ss i)) i (1+ i))
      (entmod (subst (cons 40 2.5) (assoc 40 ed) ed))))
  (if ss (sslength ss) 0))

Group code 40 is the height for both TEXT and MTEXT. Returns the number changed.

Good to know

• 2.5 here is drawing units. For a drawing in metres, say "2.5 mm on paper at 1:100" and it works out 0.25.
• Text inside blocks and attributes don't match TEXT/MTEXT. Say "attributes too" for those.

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