eintr: print-Y-axis Penultimate
C.2.4 The Not Quite Final Version of ‘print-Y-axis’
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The list constructed by the ‘Y-axis-column’ function is passed to the
‘print-Y-axis’ function, which inserts the list as a column.
(defun print-Y-axis (height full-Y-label-width)
"Insert Y axis using HEIGHT and FULL-Y-LABEL-WIDTH.
Height must be the maximum height of the graph.
Full width is the width of the highest label element."
;; Value of height and full-Y-label-width
;; are passed by print-graph.
(let ((start (point)))
(insert-rectangle
(Y-axis-column height full-Y-label-width))
;; Place point ready for inserting graph.
(goto-char start)
;; Move point forward by value of full-Y-label-width
(forward-char full-Y-label-width)))
The ‘print-Y-axis’ uses the ‘insert-rectangle’ function to insert the
Y axis labels created by the ‘Y-axis-column’ function. In addition, it
places point at the correct position for printing the body of the graph.
You can test ‘print-Y-axis’:
1. Install
Y-axis-label-spacing
Y-axis-tic
Y-axis-element
Y-axis-column
print-Y-axis
2. Copy the following expression:
(print-Y-axis 12 5)
3. Switch to the ‘*scratch*’ buffer and place the cursor where you
want the axis labels to start.
4. Type ‘M-:’ (‘eval-expression’).
5. Yank the ‘graph-body-print’ expression into the minibuffer with
‘C-y’ (‘yank)’.
6. Press <RET> to evaluate the expression.
Emacs will print labels vertically, the top one being ‘10 - ’. (The
‘print-graph’ function will pass the value of ‘height-of-top-line’,
which in this case will end up as 15, thereby getting rid of what might
appear as a bug.)
Info Catalog
eintr: Y-axis-column
eintr: print-Y-axis