diff options
Diffstat (limited to 'lisp')
| -rw-r--r-- | lisp/ChangeLog | 6 | ||||
| -rw-r--r-- | lisp/calc/calc-alg.el | 54 |
2 files changed, 58 insertions, 2 deletions
diff --git a/lisp/ChangeLog b/lisp/ChangeLog index 6d4db938378..eb11c0aaa8c 100644 --- a/lisp/ChangeLog +++ b/lisp/ChangeLog @@ -1,3 +1,9 @@ +2009-08-24 Jay Belanger <jay.p.belanger@gmail.com> + + * calc/calc-alg.el (math-trig-rewrite) + (math-hyperbolic-trig-rewrite): New functions. + (calc-simplify): Simplify trig functions when asked. + 2009-08-24 Stefan Monnier <monnier@iro.umontreal.ca> * diff-mode.el (diff-find-source-location): Avoid goto-line. diff --git a/lisp/calc/calc-alg.el b/lisp/calc/calc-alg.el index 9b3083f83d3..f4be1a5e036 100644 --- a/lisp/calc/calc-alg.el +++ b/lisp/calc/calc-alg.el @@ -51,8 +51,17 @@ (defun calc-simplify () (interactive) (calc-slow-wrapper - (calc-with-default-simplification - (calc-enter-result 1 "simp" (math-simplify (calc-top-n 1)))))) + (let ((top (calc-top-n 1))) + (if (calc-is-inverse) + (setq top + (let ((calc-simplify-mode nil)) + (math-normalize (math-trig-rewrite top))))) + (if (calc-is-hyperbolic) + (setq top + (let ((calc-simplify-mode nil)) + (math-normalize (math-hyperbolic-trig-rewrite top))))) + (calc-with-default-simplification + (calc-enter-result 1 "simp" (math-simplify top)))))) (defun calc-simplify-extended () (interactive) @@ -303,6 +312,47 @@ (defalias 'calcFunc-esimplify 'math-simplify-extended) +;;; Rewrite the trig functions in a form easier to simplify. +(defun math-trig-rewrite (fn) + "Rewrite trigonometric functions in terms of sines and cosines." + (cond + ((not (consp fn)) + fn) + ((eq (car-safe fn) 'calcFunc-sec) + (list '/ 1 (cons 'calcFunc-cos (math-trig-rewrite (cdr fn))))) + ((eq (car-safe fn) 'calcFunc-csc) + (list '/ 1 (cons 'calcFunc-sin (math-trig-rewrite (cdr fn))))) + ((eq (car-safe fn) 'calcFunc-tan) + (let ((newfn (math-trig-rewrite (cdr fn)))) + (list '/ (cons 'calcFunc-sin newfn) + (cons 'calcFunc-cos newfn)))) + ((eq (car-safe fn) 'calcFunc-cot) + (let ((newfn (math-trig-rewrite (cdr fn)))) + (list '/ (cons 'calcFunc-cos newfn) + (cons 'calcFunc-sin newfn)))) + (t + (mapcar 'math-trig-rewrite fn)))) + +(defun math-hyperbolic-trig-rewrite (fn) + "Rewrite hyperbolic functions in terms of sinhs and coshs." + (cond + ((not (consp fn)) + fn) + ((eq (car-safe fn) 'calcFunc-sech) + (list '/ 1 (cons 'calcFunc-cosh (math-hyperbolic-trig-rewrite (cdr fn))))) + ((eq (car-safe fn) 'calcFunc-csch) + (list '/ 1 (cons 'calcFunc-sinh (math-hyperbolic-trig-rewrite (cdr fn))))) + ((eq (car-safe fn) 'calcFunc-tanh) + (let ((newfn (math-hyperbolic-trig-rewrite (cdr fn)))) + (list '/ (cons 'calcFunc-sinh newfn) + (cons 'calcFunc-cosh newfn)))) + ((eq (car-safe fn) 'calcFunc-coth) + (let ((newfn (math-hyperbolic-trig-rewrite (cdr fn)))) + (list '/ (cons 'calcFunc-cosh newfn) + (cons 'calcFunc-sinh newfn)))) + (t + (mapcar 'math-hyperbolic-trig-rewrite fn)))) + ;; math-top-only is local to math-simplify, but is used by ;; math-simplify-step, which is called by math-simplify. (defvar math-top-only) |