diff options
Diffstat (limited to 'lisp/calc/calc-units.el')
| -rw-r--r-- | lisp/calc/calc-units.el | 100 |
1 files changed, 56 insertions, 44 deletions
diff --git a/lisp/calc/calc-units.el b/lisp/calc/calc-units.el index a3d037ee042..0d6f0b0e535 100644 --- a/lisp/calc/calc-units.el +++ b/lisp/calc/calc-units.el @@ -404,7 +404,7 @@ If EXPR is nil, return nil." (math-composition-to-string cexpr)))))) (defvar math-default-units-table - #s(hash-table test equal data (1 (1))) + (make-hash-table :test 'equal) "A table storing previously converted units.") (defun math-get-default-units (expr) @@ -437,20 +437,34 @@ If COMP or STD is non-nil, put that in the units table instead." (list new-units (car default-units)) math-default-units-table)))))) +(defvar calc-allow-units-as-numbers t) + (defun calc-convert-units (&optional old-units new-units) (interactive) (calc-slow-wrapper (let ((expr (calc-top-n 1)) (uoldname nil) + (unitscancel nil) + (nouold nil) unew units defunits) - (unless (math-units-in-expr-p expr t) + (if (or (not (math-units-in-expr-p expr t)) + (setq unitscancel (and + (if (get 'calc-allow-units-as-numbers 'saved-value) + (car (get 'calc-allow-units-as-numbers 'saved-value)) + calc-allow-units-as-numbers) + (eq (math-get-standard-units expr) 1)))) (let ((uold (or old-units (progn - (setq uoldname (read-string "Old units: ")) + (setq uoldname + (if unitscancel + (read-string + "(The expression is unitless when simplified) Old Units: ") + (read-string "Old units: "))) (if (equal uoldname "") (progn + (setq nouold unitscancel) (setq uoldname "1") 1) (if (string-match "\\` */" uoldname) @@ -460,47 +474,45 @@ If COMP or STD is non-nil, put that in the units table instead." (error "Bad format in units expression: %s" (nth 1 uold))) (setq expr (math-mul expr uold)))) (setq defunits (math-get-default-units expr)) - (if (equal defunits "1") - (progn - (calc-enter-result 1 "cvun" (math-simplify-units expr)) - (message "All units in expression cancel")) - (unless new-units - (setq new-units - (read-string (concat - (if uoldname - (concat "Old units: " - uoldname - ", new units") - "New units") - (if defunits - (concat - " (default " - defunits - "): ") - ": ")))) - (if (and - (string= new-units "") - defunits) - (setq new-units defunits))) - (when (string-match "\\` */" new-units) - (setq new-units (concat "1" new-units))) - (setq units (math-read-expr new-units)) - (when (eq (car-safe units) 'error) - (error "Bad format in units expression: %s" (nth 2 units))) - (if calc-ensure-consistent-units - (math-check-unit-consistency expr units)) - (let ((unew (math-units-in-expr-p units t)) - (std (and (eq (car-safe units) 'var) - (assq (nth 1 units) math-standard-units-systems))) - (comp (eq (car-safe units) '+))) - (unless (or unew std) - (error "No units specified")) - (let ((res - (if std - (math-simplify-units (math-to-standard-units expr (nth 1 std))) - (math-convert-units expr units (and uoldname (not (equal uoldname "1"))))))) - (math-put-default-units res (if comp units)) - (calc-enter-result 1 "cvun" res))))))) + (unless new-units + (setq new-units + (read-string (concat + (if (and uoldname (not nouold)) + (concat "Old units: " + uoldname + ", new units") + "New units") + (if defunits + (concat + " (default " + defunits + "): ") + ": ")))) + (if (and + (string= new-units "") + defunits) + (setq new-units defunits))) + (when (string-match "\\` */" new-units) + (setq new-units (concat "1" new-units))) + (setq units (math-read-expr new-units)) + (when (eq (car-safe units) 'error) + (error "Bad format in units expression: %s" (nth 2 units))) + (if calc-ensure-consistent-units + (math-check-unit-consistency expr units)) + (let ((unew (math-units-in-expr-p units t)) + (std (and (eq (car-safe units) 'var) + (assq (nth 1 units) math-standard-units-systems))) + (comp (eq (car-safe units) '+))) + (unless (or unew std) + (error "No units specified")) + (let* ((noold (and uoldname (not (equal uoldname "1")))) + (res + (if std + (math-simplify-units (math-to-standard-units expr (nth 1 std))) + (math-convert-units expr units noold)))) + (unless std + (math-put-default-units (if noold units res) (if comp units))) + (calc-enter-result 1 "cvun" res)))))) (defun calc-autorange-units (arg) (interactive "P") |