aboutsummaryrefslogtreecommitdiffstats
path: root/grapheps.scm
blob: 677ae344529262fa5b9f9a2ea1f02c8746b50cbd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
;;;; "grapheps.scm", Create PostScript Graphs
;;; Copyright (C) 2003 Aubrey Jaffer
;
;Permission to copy this software, to modify it, to redistribute it,
;to distribute modified versions, and to use it for any purpose is
;granted, subject to the following restrictions and understandings.
;
;1.  Any copy made of this software must include this copyright notice
;in full.
;
;2.  I have made no warranty or representation that the operation of
;this software will be error-free, and I am under no obligation to
;provide any services, by way of maintenance, update, or otherwise.
;
;3.  In conjunction with products arising from the use of this
;material, there shall be no use of my name in any advertising,
;promotional, or sales literature without prior written consent in
;each case.

(require 'array)
(require 'array-for-each)
(require 'line-i/o)
(require 'color)
(require 'resene)
(require 'saturate)
(require 'filename)

;;@code{(require 'eps-graph)}
;;
;;@noindent
;;This is a graphing package creating encapsulated-PostScript files.
;;Its motivations and design choice are described in
;;@url{http://swiss.csail.mit.edu/~jaffer/Docupage/grapheps}
;;
;;@noindent
;;A dataset to be plotted is taken from a 2-dimensional array.
;;Corresponding coordinates are in rows.  Coordinates from any
;;pair of columns can be plotted.

;;; String append which accepts numbers, symbols, vectors, and lists.
(define (scheme->ps . args)
  (apply string-append
	 (map (lambda (arg)
		(cond ((number? arg) (number->string arg))
		      ((symbol? arg) (symbol->string arg))
		      ((or (vector? arg) (list? arg))
		       (string-append
			"[ "
			(apply string-append
			       (map (lambda (x) (scheme->ps x " "))
				    (if (vector? arg) (vector->list arg) arg)))
			"]"))
		      (else arg)))
	      args)))

;;; Capture for %%Title
(define *plot-title* #f)

;; Remember arrays so each is output only once.
(define *plot-arrays* '())

;;@args filename.eps size elt1 ...
;;@1 should be a string naming an output file to be created.  @2
;;should be an exact integer, a list of two exact integers, or #f.
;;@3, ... are values returned by graphing primitives described here.
;;
;;@0 creates an @dfn{Encapsulated-PostScript} file named @1 containing
;;graphs as directed by the @3, ... arguments.
;;
;;The size of the graph is determined by the @2 argument.  If a list
;;of two integers, they specify the width and height.  If one integer,
;;then that integer is the width and the height is 3/4 of the width.
;;If #f, the graph will be 800 by 600.
(define (create-postscript-graph filename size . args)
  (define xsize (cond ((pair? size) (car size))
		      ((number? size) size)
		      (else 800)))
  (let ((ysize (if (and (pair? size) (pair? (cdr size)))
		   (cadr size)
		   (quotient (* 3 xsize) 4))))
    (cond ((provided? 'inexact)
	   (set! xsize (inexact->exact (round xsize)))
	   (set! ysize (inexact->exact (round ysize)))))
    (call-with-output-file filename
      (lambda (oprt)
	(define (write-lines lines)
	  (for-each (lambda (line) (if (list? line)
				       (write-lines line)
				       (write-line line oprt)))
		    lines))
	(write-line "%!PS-Adobe-3.0 EPSF-3.0" oprt)
	(write-line (scheme->ps "%%BoundingBox: 0 0 " xsize " " ysize) oprt)
	(write-line (scheme->ps "%%Title: " (or *plot-title* filename)) oprt)
	(write-line (scheme->ps "%%EndComments: ") oprt)
	(write-line (scheme->ps "0 0 " xsize " " ysize) oprt)
	(call-with-input-file (in-vicinity (library-vicinity) "grapheps.ps")
	  (lambda (iprt)
	    (do ((line (read-line iprt) (read-line iprt)))
		((eof-object? line))
	      (write-line line oprt))))
	(for-each (lambda (pair) (write-array-def (cdr pair) (car pair) oprt))
		  *plot-arrays*)
	(write-lines args)
	(newline oprt)
	(write-line "grestore" oprt)
	(write-line "end" oprt)
	(write-line "showpage" oprt)))
    (set! *plot-title* #f)
    (set! *plot-arrays* '())))

(define (write-array-def name array oprt)
  (define row-length (cadr (array-dimensions array)))
  (define idx 0)
  (set! idx row-length)
  (write-line (scheme->ps "/" name) oprt)
  (write-line "[" oprt)
  (display " [" oprt)
  (array-for-each
   (lambda (elt)
     (cond ((zero? idx)
	    (write-line "]" oprt)
	    (display " [" oprt)))
     (display (scheme->ps "	" elt) oprt)
     (set! idx (modulo (+ 1 idx) row-length)))
   array)
  (write-line "]" oprt)
  (write-line "] def" oprt))

;;; Arrays are named and cached in *plot-arrays*.
(define (import-array array)
  (cond ((assq array *plot-arrays*) => cdr)
	(else
	 (let ((name (gentemp)))
	   (set! *plot-arrays* (cons (cons array name) *plot-arrays*))
	   name))))

;;@noindent
;;These graphing procedures should be called as arguments to
;;@code{create-postscript-graph}.  The order of these arguments is
;;significant; PostScript graphics state is affected serially from the
;;first @var{elt} argument to the last.

;;@body
;;Pushes a rectangle for the whole encapsulated page onto the
;;PostScript stack.  This pushed rectangle is an implicit argument to
;;@code{partition-page} or @code{setup-plot}.
(define (whole-page) 'whole-page)

;;@menu
;;* Column Ranges::
;;* Drawing the Graph::
;;* Graphics Context::
;;* Rectangles::
;;* Legending::
;;* Legacy Plotting::
;;* Example Graph::
;;@end menu
;;
;;@node Column Ranges, Drawing the Graph, PostScript Graphing, PostScript Graphing
;;@subsubsection Column Ranges

;;@noindent
;;A @dfn{range} is a list of two numbers, the minimum and the maximum.
;;@cindex range
;;Ranges can be given explicity or computed in PostScript by
;;@code{column-range}.

;;@body
;;Returns the range of values in 2-dimensional @1 column @2.
(define (column-range array k)
  (set! array (import-array array))
  (scheme->ps array " " k " column-range"))

;;@body
;;Expands @1 by @2/100 on each end.
(define (pad-range range p) (scheme->ps range " " p " pad-range"))

;;@body
;;Expands @1 to round number of ticks.
(define (snap-range range) (scheme->ps range " snap-range"))

;;@args range1 range2 ...
;;Returns the minimal range covering all @1, @2, ...
(define (combine-ranges rng1 . rngs)
  (define (loop rngs)
    (cond ((null? rngs) "")
	  (else (scheme->ps " " (car rngs) (loop (cdr rngs))
			    " combine-ranges"))))
  (scheme->ps rng1 (loop rngs)))

;;@args x-range y-range pagerect
;;@args x-range y-range
;;@1 and @2 should each be a list of two numbers or the value returned
;;by @code{pad-range}, @code{snap-range}, or @code{combine-range}.
;;@3 is the rectangle bounding the graph to be drawn; if missing, the
;;rectangle from the top of the PostScript stack is popped and used.
;;
;;Based on the given ranges, @0 sets up scaling and margins for making
;;a graph.  The margins are sized proportional to the @var{fontheight}
;;value at the time of the call to setup-plot.  @0 sets two variables:
;;
;;@table @var
;;@item plotrect
;;The region where data points will be plotted.
;;@item graphrect
;;The @3 argument to @0.  Includes plotrect, legends, etc.
;;@end table
(define (setup-plot xrange yrange . pagerect)
  (if (null? pagerect)
      (scheme->ps xrange " " yrange " setup-plot")
      (scheme->ps (car pagerect) " " xrange " " yrange " setup-plot")))

;;@node Drawing the Graph, Graphics Context, Column Ranges, PostScript Graphing
;;@subsubsection Drawing the Graph

;;@body
;;Plots points with x coordinate in @2 of @1 and y coordinate @3 of
;;@1.  The symbol @4 specifies the type of glyph or drawing style for
;;presenting these coordinates.
(define (plot-column array x-column y-column proc3s)
  (set! array (import-array array))
  (scheme->ps "[ " array " " x-column " " y-column " ] "  proc3s
		  " plot-column"))

;;@noindent
;;The glyphs and drawing styles available are:
;;
;;@table @code
;;@item line
;;Draws line connecting points in order.
;;@item mountain
;;Fill area below line connecting points.
;;@item cloud
;;Fill area above line connecting points.
;;@item impulse
;;Draw line from x-axis to each point.
;;@item bargraph
;;Draw rectangle from x-axis to each point.
;;@item disc
;;Solid round dot.
;;@item point
;;Minimal point -- invisible if linewidth is 0.
;;@item square
;;Square box.
;;@item diamond
;;Square box at 45.o
;;@item plus
;;Plus sign.
;;@item cross
;;X sign.
;;@item triup
;;Triangle pointing upward
;;@item tridown
;;Triangle pointing downward
;;@item pentagon
;;Five sided polygon
;;@item circle
;;Hollow circle
;;@end table


;;@node Graphics Context, Rectangles, Drawing the Graph, PostScript Graphing
;;@subsubsection Graphics Context

;;@body
;;Saves the current graphics state, executes @1, then restores
;;to saved graphics state.
(define (in-graphic-context . args)
  (append '("gpush") args '("gpop")))

;;@args color
;;@1 should be a string naming a Resene color, a saturate color, or a
;;number between 0 and 100.
;;
;;@0 sets the PostScript color to the color of the given string, or a
;;grey value between black (0) and white (100).
(define (set-color clrn)
  (define clr
    (cond ((color? clrn) clrn)
	  ((number? clrn) (* 255/100 clrn))
	  ((or (eq? 'black clrn)
	       (and (string? clrn) (string-ci=? "black" clrn))) 0)
	  ((or (eq? 'white clrn)
	       (and (string? clrn) (string-ci=? "white" clrn))) 255)
	  (else (or (saturate clrn) (resene clrn)
		    (string->color (if (symbol? clrn)
				       (symbol->string clrn)
				       clrn))))))
  (define (num->str x)
    (define num (inexact->exact (round (+ 1000 (* x 999/255)))))
    (scheme->ps "." (substring (number->string num) 1 4) " "))
  (cond ((number? clr) (string-append (num->str clr) " setgray"))
	(clr (apply scheme->ps
		    (append (map num->str (color->sRGB clr)) '(setrgbcolor))))
	(else "")))

;;@body
;;@1 should be a (case-sensitive) string naming a PostScript font.
;;@2 should be a positive real number.
;;
;;@0 Changes the current PostScript font to @1 with height equal to
;;@2.  The default font is Helvetica (12pt).
(define (set-font name fontheight)
  (scheme->ps "/fontsize " fontheight " def /" name " fontsize selectfont"))

;;@noindent
;;The base set of PostScript fonts is:
;;
;;@multitable @columnfractions .20 .25 .25 .30
;;@item Times @tab Times-Italic @tab Times-Bold @tab Times-BoldItalic
;;@item Helvetica @tab Helvetica-Oblique @tab Helvetica-Bold @tab Helvetica-BoldOblique
;;@item Courier @tab Courier-Oblique @tab Courier-Bold @tab Courier-BoldOblique
;;@item Symbol
;;@end multitable

;;@noindent
;;Line parameters do no affect fonts; they do effect glyphs.

;;@body
;;The default linewidth is 1.  Setting it to 0 makes the lines drawn
;;as skinny as possible.  Linewidth must be much smaller than
;;glyphsize for readable glyphs.
(define (set-linewidth w) (scheme->ps w " setlinewidth"))

;;@args j k
;;Lines are drawn @1-on @2-off.
;;@args j
;;Lines are drawn @1-on @1-off.
;;@args
;;Turns off dashing.
(define (set-linedash . args) (scheme->ps args " 0 setdash"))

;;@body
;;Sets the (PostScript) variable glyphsize to @1.  The default
;;glyphsize is 6.
(define (set-glyphsize w) (scheme->ps "/glyphsize " w " def"))

;;@noindent
;;The effects of @code{clip-to-rect} are also part of the graphic
;;context.


;;@node Rectangles, Legending, Graphics Context, PostScript Graphing
;;@subsubsection Rectangles

;;@noindent
;;A @dfn{rectangle} is a list of 4 numbers; the first two elements are
;;the x and y coordinates of lower left corner of the rectangle.  The
;;other two elements are the width and height of the rectangle.

;;@body
;;Pushes a rectangle for the whole encapsulated page onto the
;;PostScript stack.  This pushed rectangle is an implicit argument to
;;@code{partition-page} or @code{setup-plot}.
(define (whole-page) 'whole-page)

;;@body
;;Pops the rectangle currently on top of the stack and pushes @1 * @2
;;sub-rectangles onto the stack in decreasing y and increasing x order.
;;If you are drawing just one graph, then you don't need @0.
(define (partition-page xparts yparts)
  (scheme->ps xparts " " yparts " partition-page"))

;;@body
;;The rectangle where data points should be plotted.  @0 is set by
;;@code{setup-plot}.
(define plotrect 'plotrect)

;;@body
;;The @var{pagerect} argument of the most recent call to
;;@code{setup-plot}.  Includes plotrect, legends, etc.
(define graphrect 'graphrect)

;;@body
;;fills @1 with the current color.
(define (fill-rect rect) (scheme->ps rect " fill-rect"))

;;@body
;;Draws the perimiter of @1 in the current color.
(define (outline-rect rect) (scheme->ps rect " outline-rect"))

;;@body
;;Modifies the current graphics-state so that nothing will be drawn
;;outside of the rectangle @1.  Use @code{in-graphic-context} to limit
;;the extent of @0.
(define (clip-to-rect rect) (scheme->ps rect " clip-to-rect"))


;;@node Legending, Legacy Plotting, Rectangles, PostScript Graphing
;;@subsubsection Legending

;;@args title subtitle
;;@args title
;;Puts a @1 line and an optional @2 line above the @code{graphrect}.
(define (title-top title . subtitle)
  (set! *plot-title* title)
  (scheme->ps "(" title ") ("
	      (if (null? subtitle) "" (car subtitle))
	      ") title-top"))

;;@args title subtitle
;;@args title
;;Puts a @1 line and an optional @2 line below the @code{graphrect}.
(define (title-bottom title . subtitle)
  (set! *plot-title* title)
  (scheme->ps "(" title ") ("
	      (if (null? subtitle) "" (car subtitle))
	      ") title-bottom"))

;;@body
;;These edge coordinates of @code{graphrect} are suitable for passing
;;as the first argument to @code{rule-horizontal}.
(define topedge 'topedge)
(define bottomedge 'bottomedge)

;;@body
;;These edge coordinates of @code{graphrect} are suitable for passing
;;as the first argument to @code{rule-vertical}.
(define leftedge 'leftedge)
(define rightedge 'rightedge)

;;@body
;;The margin-templates are strings whose displayed width is used to
;;reserve space for the left and right side numerical legends.
;;The default values are "-.0123456789".
(define (set-margin-templates left right)
  (scheme->ps "/lmargin-template (" left ") def "
	      "/rmargin-template (" right ") def"))

;;@body
;;Draws a vertical ruler with X coordinate @1 and labeled with string
;;@2.  If @3 is positive, then the ticks are @3 long on the right side
;;of @1; and @2 and numeric legends are on the left.  If @3 is
;;negative, then the ticks are -@3 long on the left side of @1; and @2
;;and numeric legends are on the right.
(define (rule-vertical x-coord text tick-width)
  (scheme->ps x-coord " (" text ") " tick-width " rule-vertical"))

;;@body
;;Draws a horizontal ruler with X coordinate @1 and labeled with
;;string @2.  If @3 is positive, then the ticks are @3 long on the
;;right side of @1; and @2 and numeric legends are on the left.  If @3
;;is negative, then the ticks are -@3 long on the left side of @1; and
;;@2 and numeric legends are on the right.
(define (rule-horizontal x-coord text tick-height)
  (scheme->ps x-coord " (" text ") " tick-height " rule-horizontal"))

;;@body
;;Draws the y-axis.
(define (y-axis) 'y-axis)
;;@body
;;Draws the x-axis.
(define (x-axis) 'x-axis)
;;@body
;;Draws vertical lines through @code{graphrect} at each tick on the
;;vertical ruler.
(define (grid-verticals) 'grid-verticals)
;;@body
;;Draws horizontal lines through @code{graphrect} at each tick on the
;;horizontal ruler.
(define (grid-horizontals) 'grid-horizontals)

;;@node Legacy Plotting, Example Graph, Legending, PostScript Graphing
;;@subsubsection Legacy Plotting

(define (graph:plot tmp data xlabel ylabel . histogram?)
  (set! histogram? (if (null? histogram?) #f (car histogram?)))
  (if (list? data)
      (let ((len (length data))
	    (nra (make-array (A:floR64b) (length data) 2)))
	(do ((idx 0 (+ 1 idx))
	     (lst data (cdr lst)))
	    ((>= idx len)
	     (set! data nra))
	  (array-set! nra (caar lst) idx 0)
	  (array-set! nra (if (list? (cdar lst)) (cadar lst) (cdar lst))
		      idx 1))))
  (create-postscript-graph
   tmp (or graph:dimensions '(600 300))
   (whole-page) (setup-plot (column-range data 0) (column-range data 1))
   (outline-rect plotrect)
   (x-axis) (y-axis)
   (plot-column data 0 1 (if histogram? 'bargraph 'line))
   (rule-vertical leftedge ylabel 10)
   (rule-horizontal bottomedge xlabel 10)))

(define (graph:plot-function tmp func vlo vhi . npts)
  (set! npts (if (null? npts) 200 (car npts)))
  (let ((dats (make-array (A:floR64b) npts 2)))
    (array-index-map! (make-shared-array dats (lambda (idx) (list idx 0)) npts)
		      (lambda (idx)
			(+ vlo (* (- vhi vlo) (/ idx (+ -1 npts))))))
    (array-map! (make-shared-array dats (lambda (idx) (list idx 1)) npts)
		func
		(make-shared-array dats (lambda (idx) (list idx 0)) npts))
    (graph:plot tmp dats "" "")))

;;@body
;;A list of the width and height of the graph to be plotted using
;;@code{plot}.
(define graph:dimensions #f)

;;@args func x1 x2 npts
;;@args func x1 x2
;;Creates and displays using @code{(system "gv tmp.eps")} an
;;encapsulated PostScript graph of the function of one argument @1
;;over the range @2 to @3.  If the optional integer argument @4 is
;;supplied, it specifies the number of points to evaluate @1 at.
;;
;;@defunx plot coords x-label y-label
;;@var{coords} is a list or vector of coordinates, lists of x and y
;;coordinates.  @var{x-label} and @var{y-label} are strings with which
;;to label the x and y axes.
(define (plot . args)
  (call-with-tmpnam
   (lambda (tmp)
     (if (procedure? (car args))
	 (apply graph:plot-function tmp args)
	 (apply graph:plot tmp args))
     (system (string-append "gv '" tmp "'")))
   ".eps"))


;;@node Example Graph,  , Legacy Plotting, PostScript Graphing
;;@subsubsection Example Graph

;;@noindent
;;The file @file{am1.5.html}, a table of solar irradiance, is fetched
;;with @samp{wget} if it isn't already in the working directory.  The
;;file is read and stored into an array, @var{irradiance}.
;;
;;@code{create-postscript-graph} is then called to create an
;;encapsulated-PostScript file, @file{solarad.eps}.  The size of the
;;page is set to 600 by 300.  @code{whole-page} is called and leaves
;;the rectangle on the PostScript stack.  @code{setup-plot} is called
;;with a literal range for x and computes the range for column 1.
;;
;;Two calls to @code{top-title} are made so a different font can be
;;used for the lower half.  @code{in-graphic-context} is used to limit
;;the scope of the font change.  The graphing area is outlined and a
;;rule drawn on the left side.
;;
;;Because the X range was intentionally reduced,
;;@code{in-graphic-context} is called and @code{clip-to-rect} limits
;;drawing to the plotting area.  A black line is drawn from data
;;column 1.  That line is then overlayed with a mountain plot of the
;;same column colored "Bright Sun".
;;
;;After returning from the @code{in-graphic-context}, the bottom ruler
;;is drawn.  Had it been drawn earlier, all its ticks would have been
;;painted over by the mountain plot.
;;
;;The color is then changed to @samp{seagreen} and the same graphrect
;;is setup again, this time with a different Y scale, 0 to 1000.  The
;;graphic context is again clipped to @var{plotrect}, linedash is set,
;;and column 2 is plotted as a dashed line.  Finally the rightedge is
;;ruled.  Having the line and its scale both in green helps
;;disambiguate the scales.

;;@example
;;(require 'eps-graph)
;;(require 'line-i/o)
;;(require 'string-port)
;;
;;(define irradiance
;;  (let ((url "http://www.pv.unsw.edu.au/am1.5.html")
;;        (file "am1.5.html"))
;;    (define (read->list line)
;;      (define elts '())
;;      (call-with-input-string line
;;        (lambda (iprt) (do ((elt (read iprt) (read iprt)))
;;                           ((eof-object? elt) elts)
;;                         (set! elts (cons elt elts))))))
;;    (if (not (file-exists? file))
;;        (system (string-append "wget -c -O" file " " url)))
;;    (call-with-input-file file
;;      (lambda (iprt)
;;        (define lines '())
;;        (do ((line (read-line iprt) (read-line iprt)))
;;            ((eof-object? line)
;;             (let ((nra (make-array (A:floR64b)
;;                                      (length lines)
;;                                      (length (car lines)))))
;;               (do ((lns lines (cdr lns))
;;                    (idx (+ -1 (length lines)) (+ -1 idx)))
;;                   ((null? lns) nra)
;;                 (do ((kdx (+ -1 (length (car lines))) (+ -1 kdx))
;;                      (lst (car lns) (cdr lst)))
;;                     ((null? lst))
;;                   (array-set! nra (car lst) idx kdx)))))
;;          (if (and (positive? (string-length line))
;;                   (char-numeric? (string-ref line 0)))
;;              (set! lines (cons (read->list line) lines))))))))
;;
;;(let ((xrange '(.25 2.5)))
;;  (create-postscript-graph
;;   "solarad.eps" '(600 300)
;;   (whole-page)
;;   (setup-plot xrange (column-range irradiance 1))
;;   (title-top
;;    "Solar Irradiance   http://www.pv.unsw.edu.au/am1.5.html")
;;   (in-graphic-context
;;    (set-font "Helvetica-Oblique" 12)
;;    (title-top
;;     ""
;;     "Key Centre for Photovoltaic Engineering UNSW - Air Mass 1.5 Global Spectrum"))
;;   (outline-rect plotrect)
;;   (rule-vertical leftedge "W/(m^2.um)" 10)
;;   (in-graphic-context (clip-to-rect plotrect)
;;                       (plot-column irradiance 0 1 'line)
;;                       (set-color "Bright Sun")
;;                       (plot-column irradiance 0 1 'mountain)
;;                       )
;;   (rule-horizontal bottomedge "Wavelength in .um" 5)
;;   (set-color 'seagreen)
;;
;;   (setup-plot xrange '(0 1000) graphrect)
;;   (in-graphic-context (clip-to-rect plotrect)
;;                       (set-linedash 5 2)
;;                       (plot-column irradiance 0 2 'line))
;;   (rule-vertical rightedge "Integrated .W/(m^2)" -10)
;;   ))
;;
;;(system "gv solarad.eps")
;;@end example