[cl-pdf-devel] Histogram bug

[Björn Lindberg]

It seems that it is supposed to be possible to give a format string
for the values on the y axis when creating a histogram instance like
so:

(make-instance 'pdf:histogram ...
               :y-axis-options '(:format-string "foo! ~A"))

However, first of all this slot will never be set because there is no
initarg for it in the class value-axis. Secondly, even if it was, it
would be unconditionally clobbered in the compute-scale function.

Below is a patch to chart.lisp with a suggested modification which
remedies both problems.


Björn


--- chart.bak.lisp      2004-11-30 12:36:47.000000000 +0100
+++ chart.lisp  2004-11-30 12:58:30.000000000 +0100
@@ -46,7 +46,7 @@
    (axis-min :accessor axis-min)
    (axis-max :accessor axis-max)
    (nb-subticks :accessor nb-subticks)
-   (format-string :accessor format-string)
+   (format-string :accessor format-string :initform nil :initarg :format-string)
    ))
 
 (defmethod initialize-instance :after ((axis value-axis) &rest init-options &key &allow-other-keys)
@@ -111,10 +111,11 @@
          (axis-scale axis) (/ (axis-size axis)(- (axis-max axis) (axis-min axis)))
          (ticks-separation axis)(/ (axis-size axis) (1- (nb-ticks axis)))
          (format-string axis)
-         (if (integer-tick axis)
-             "~d"
-             (format nil "~~,~df" nfrac))
-         (ticks-positions axis)(make-array (nb-ticks axis)))
+         (or (format-string axis)
+             (if (integer-tick axis)
+                 "~d"
+                 (format nil "~~,~df" nfrac)))
+         (ticks-positions axis) (make-array (nb-ticks axis)))
     (loop for tick from 0 below (nb-ticks axis)
          for pos from 0 by (ticks-separation axis) do
          (setf (aref (ticks-positions axis) tick) pos))))