simple scatterplot

[Mike Hounsome]

I'm converting my TurboBasic programs to PBCC6 and am still a beginner with PBCC. I need a simple way of plotting a scatterplot and have looked at the examples and on the forum but all of them seem overly complex when all I want to do is to plot several X-Y points. I have my points in a 2-dimensional array a(1:n,1:2) and I have maxx, minx, maxy and miny so it should be a doddle to plot the points but all the examples a way too complex. Can anybody give me a simple example so that I can get to know the techniques?

[Paul Dixon]

Mike,
does this help?

Paul.

'PBCC6 program
FUNCTION PBMAIN () AS LONG

LOCAL x,y,r AS LONG

  CONSOLE SET LOC 1,1
  CONSOLE SET SCREEN 5,30
  GRAPHIC WINDOW "test",100,100,800,500 TO hBmp&

  GRAPHIC ATTACH hBmp&, 0
  GRAPHIC CLEAR %BLACK

  FOR r = 1 TO 100
      x = RND(1,800)
      y = RND(1,500)
      GRAPHIC SET PIXEL (x,y),%YELLOW
  NEXT


  PRINT "Press any key to end."
  CONSOLE SET FOCUS
  WAITKEY$
END FUNCTION

[Mike Hounsome]

That's a good start, Paul. I've now got to find how to draw and label the axes and how to set the size of the points but that's got the basics upon which I can build. Thank you.

[Mike Hounsome]

Now what I have to do is to scale x and y to the size of the graphic window, set the size of the points and draw and label the axes:

'PBCC6 program
FUNCTION PBMAIN () AS LONG

LOCAL x,y,r,n AS LONG
file$="ltest.dat"
OPEN file$ FOR INPUT AS #1
INPUT#1,n   'first line of file has the number of pairs
            'all other lines have pairs of numbers separated by commas
DIM a(n,2) AS DOUBLE
  CONSOLE SET LOC 1,1
  CONSOLE SET SCREEN 15,25
  GRAPHIC WINDOW "test",300,300,800,500 TO hBmp&
  GRAPHIC ATTACH hBmp&, 0
  GRAPHIC CLEAR %BLACK
  FOR r = 1 TO n
      INPUT#1,a(r,1),a(r,2)
      x = a(r,1)
      y = a(r,2)
      PRINT a(r,1),a(r,2)
      GRAPHIC SET PIXEL (x,y),%YELLOW
  NEXT r
  PRINT "Press any key to end."
  CONSOLE SET FOCUS
  WAITKEY$
CLOSE
END FUNCTION

[Dave Biggs]

Now what I have to do is to scale x and y to the size of the graphic window,..

Easier to scale the Graphic Window to suit the data

'PBCC6 program
FUNCTION PBMAIN () AS LONG
 
LOCAL x,y,r,n,xmax,ymax, hFont AS LONG
file$="ltest.dat"                 ' see comments at end of source
OPEN file$ FOR INPUT AS #1
INPUT#1,n   'first line of file has the number of pairs
            'all other lines have pairs of numbers separated by commas
DIM a(1 TO n, 1 TO 2) AS DOUBLE
  CONSOLE SET LOC 1,1
  CONSOLE SET SCREEN 15,25
  GRAPHIC WINDOW "test",300,300,800,500 TO hBmp&
  GRAPHIC ATTACH hBmp&, 0
  GRAPHIC CLEAR %BLACK
  GRAPHIC COLOR %YELLOW, %BLACK
 
  FOR r = 1 TO n
      INPUT#1,a(r,1),a(r,2)
      xmax = MAX(a(r,1), xmax) : ymax = MAX(a(r,2),ymax)
  NEXT
  PRINT "xmax" xmax, "ymax" ymax                    ' eg 100, 90
  GRAPHIC SCALE (-5,-10) - (xmax+10, ymax+15)       ' customize coordinates to suit data
  '  GRAPHIC SCALE (-5, ymax+10) - (xmax+10,-15)       ' eg change orientation
 
  GRAPHIC SET POS (xmax/2,-9)
  GRAPHIC PRINT "X-AXIS"
 
  GRAPHIC LINE (0,0) - (0,ymax+5)                   ' x axis
  FOR r = 0 TO ymax STEP n                          ' marks
    GRAPHIC LINE (0,r) - (-1,r)
    GRAPHIC SET POS STEP (-2,0)
    GRAPHIC PRINT r                                 ' scale values
  NEXT
 
  FONT NEW "Arial", 8, 0, 0, 0, 900 TO hFont        ' true type font for escapement
  GRAPHIC SET FONT hFont
  GRAPHIC SET POS (-5,ymax/2)
  GRAPHIC PRINT "Y-AXIS"
  GRAPHIC SET FONT 0                                ' default font (MS Sans Serif 8 point)
 
  GRAPHIC LINE (0,0) - (xmax+5,0)                   ' y axis
  FOR r = 0 TO xmax STEP n                          ' marks
    GRAPHIC LINE (r,0) - (r,-2)
    GRAPHIC SET POS STEP (0,-2)
    GRAPHIC PRINT r                                 ' scale values
  NEXT
 
  FOR r = 1 TO n
      x = a(r,1)
      y = a(r,2)
      PRINT a(r,1),a(r,2)
      GRAPHIC ELLIPSE (x-1,y-1) - (x+1,y+1), %RED, %RED
      GRAPHIC SET PIXEL (x,y), %YELLOW
  NEXT r
  PRINT "Press any key to end."
  CONSOLE SET FOCUS
  WAITKEY$
CLOSE
END FUNCTION
 
#IF 0
' sample data for ltest.dat
 
10
10,5
20,10
30,20
40,30
50,40
60,50
70,60
80,70
90,80
100,90
 
#ENDIF

[Mike Hounsome]

Thanks, Dave. That gives me lots of ideas. I've changed a couple of things: I've set the font to Lucida Console which I think looks nicer; was there a particular reason for you choosing Arial and the default font? I've also set the points using an X character rather than drawing an ellipse (just personal preference). Now I'm trying to work out the scaling so that the numbers print at sensible intervals. This could be difficult! I have also changed the data at the end of the file to be my own test data. Does the #IF mean that if the file is not present it would use those data?

 'PBCC6 program
FUNCTION PBMAIN () AS LONG

LOCAL x,y,r,n,xmax,ymax, hFont AS LONG
file$="ltest.dat"                 ' see comments at end of source
b$="Title"
xaxis$="X-Axis"
yaxis$="Y-Axis"
OPEN file$ FOR INPUT AS #1
INPUT#1,n
DIM a(1 TO n, 1 TO 2) AS DOUBLE
  CONSOLE SET LOC 1,1
  CONSOLE SET SCREEN 15,25
  GRAPHIC WINDOW "test",300,300,800,500 TO hBmp&
  GRAPHIC ATTACH hBmp&, 0
  GRAPHIC CLEAR %WHITE
  GRAPHIC COLOR %BLACK, %WHITE
  GRAPHIC FONT "Lucida Console", 12, 0
  GRAPHIC PRINT SPC((80-LEN(b$))/2);b$
  FOR r = 1 TO n
      INPUT#1,a(r,1),a(r,2)
      xmax = MAX(a(r,1), xmax) : ymax = MAX(a(r,2),ymax)
  NEXT
  PRINT "xmax" xmax, "ymax" ymax
'  GRAPHIC SCALE (-5,-10) - (xmax+10, ymax+15)       ' customize coordinates to suit data
  GRAPHIC SCALE (-5, ymax+10) - (xmax+10,-15)       ' eg change orientation

  GRAPHIC SET POS (xmax/2,-9)
  GRAPHIC PRINT xaxis$

  GRAPHIC LINE (0,0) - (0,ymax+5)                   ' x axis
  FOR r = 0 TO ymax STEP n                          ' marks
    GRAPHIC LINE (0,r) - (-1,r)
    GRAPHIC SET POS STEP (-2,0)
    GRAPHIC PRINT r                                 ' scale values
  NEXT

REM   FONT NEW "Arial", 8, 0, 0, 0, 900 TO hFont        ' true type font for escapement
REM   GRAPHIC SET FONT hFont
  GRAPHIC SET POS (-5,ymax/2)
  GRAPHIC PRINT yaxis$
REM   GRAPHIC SET FONT 0                                ' default font (MS Sans Serif 8 point)

  GRAPHIC LINE (0,0) - (xmax+5,0)                   ' y axis
  FOR r = 0 TO xmax STEP n                          ' marks
    GRAPHIC LINE (r,0) - (r,-2)
    GRAPHIC SET POS STEP (0,-2)
    GRAPHIC PRINT r                                 ' scale values
  NEXT

  FOR r = 1 TO n
      x = a(r,1)
      y = a(r,2)
      PRINT a(r,1),a(r,2)
      GRAPHIC SET POS (x,y)
      GRAPHIC PRINT "X"
REM       GRAPHIC ELLIPSE (x-1,y-1) - (x+1,y+1), %RED, %RED
REM       GRAPHIC SET PIXEL (x,y), %YELLOW
  NEXT r
  PRINT "Press any key to end."
  CONSOLE SET FOCUS
  WAITKEY$
CLOSE
END FUNCTION

#IF 0
' sample data for ltest.dat

11
14,61
17,24
24,65
25,69
27,54
33,93
34,17
37,89
40,100
41,90
42,97

#ENDIF

[Dave Biggs]

Hi Mike,

I've tweaked the code a bit more. I didn't have any reason for the font choices before - just needed to change from default to any true type font to demo use of a rotated label for the Y-Axis.

In the code below I have added adjustment of your "X" positioning so that the center of the character lies on the point to be plotted.

I've ajusted the scale marks and added point value display in the caption bar upon mouse-click (clear w/ double-click) too.

The #IF 0 / #ENDIF metastatements just mark a comment block that the compiler should ignore.

'PBCC6 program
FUNCTION PBMAIN () AS LONG
 
LOCAL x,y,r,n,xmax, ymax, hFont1, hFont2 AS LONG
file$="ltest.dat"                 ' see example data at end of source
b$="Title"
xaxis$="X-Axis"
yaxis$="Y-Axis"
OPEN file$ FOR INPUT AS #1
INPUT#1,n
DIM a(1 TO n, 1 TO 2) AS DOUBLE
  CONSOLE SET LOC 1,1
  CONSOLE SET SCREEN 15,25
  GRAPHIC WINDOW "test",300,300,800,500 TO hBmp&
  GRAPHIC ATTACH hBmp&, 0
  GRAPHIC CLEAR %WHITE
  GRAPHIC COLOR %BLACK, %WHITE
  FONT NEW "Lucida Console", 12, 0, 0, 0 ,0 TO hFont1      ' set up fonts to be used
  FONT NEW "Lucida Console", 12, 0, 0, 0, 900 TO hFont2    ' rotated font (must be true type)
 
  FOR r = 1 TO n
      INPUT#1,a(r,1),a(r,2)
      xmax = MAX(a(r,1), xmax) : ymax = MAX(a(r,2),ymax)
  NEXT
  PRINT "xmax" xmax, "ymax" ymax
  GRAPHIC SCALE (-5, ymax+10) - (xmax+10,-15)       ' set scale / orientation
 
  GRAPHIC SET FONT hFont1                           ' set font
  GRAPHIC SET POS (xmax/2, ymax+8) : GRAPHIC PRINT b$
  GRAPHIC SET POS (xmax/2,-9)      : GRAPHIC PRINT xaxis$
 
  GRAPHIC LINE (0,0) - (0,ymax+5)                   ' x axis
  FOR r = 0 TO ymax STEP 5                          ' marks
    IF r MOD 10 = 0 THEN
      GRAPHIC LINE (0,r) - (-.5,r)
      GRAPHIC SET POS STEP (-3.3,1.5)
      GRAPHIC PRINT r                               ' scale values
    ELSE
      GRAPHIC LINE (0,r) - (-.2,r)
    END IF
  NEXT
 
  GRAPHIC SET FONT hFont2                           ' font2 rotated font
  GRAPHIC SET POS (-4.5,ymax/2)
  GRAPHIC PRINT yaxis$
  GRAPHIC SET FONT hFont1                           ' font1
 
  GRAPHIC LINE (0,0) - (xmax+5,0)                   ' y axis
  FOR r = 0 TO xmax STEP 5                          ' marks
    IF r MOD 10 = 0 THEN
      GRAPHIC LINE (r,0) - (r,-2)
      GRAPHIC SET POS STEP (-1,-2)
      GRAPHIC PRINT r                               ' scale values
    ELSE
      GRAPHIC LINE (r,0) - (r,-1)
    END IF
  NEXT
 
  FOR r = 1 TO n
      x = a(r,1) - GRAPHIC(CELL.SIZE.X)/2           ' adjust point positions to suit "X" center
      y = a(r,2) + GRAPHIC(CELL.SIZE.Y)/2
      PRINT a(r,1),a(r,2)
      GRAPHIC SET POS (x,y)
      GRAPHIC PRINT "X"
      GRAPHIC SET POS (1, ymax+8) : GRAPHIC PRINT "Click screen for values"
  NEXT r
 
  DO WHILE GRAPHIC(DC) <> 0                           ' loop while Graphic Window exists
    GRAPHIC INKEY$ TO sKey$                           ' check keyboard input to graphic window
    SLEEP 1
    IF sKey$ <> "" THEN EXIT LOOP                     ' any key to quit loop (focus goes to console)
 
    GRAPHIC WINDOW CLICK hBmp& TO Clk&, x&, y&        ' check if graphic window clicked
    IF Clk& = 2 THEN                                  ' Double Click
      GRAPHIC SET POS (1, ymax+8) : GRAPHIC SET CAPTION "test" ' clear old pos info
    ELSEIF Clk& = 1 THEN
      GRAPHIC SET POS (1, ymax+8) : GRAPHIC PRINT "                       "
      GRAPHIC SET CAPTION " x:"+STR$(x&)+", y:"+STR$(y&)  ' show 'click' position in graphic window
    END IF
  LOOP
 
  PRINT "Press any key to end."
  CONSOLE SET FOCUS
  WAITKEY$
 CLOSE
END FUNCTION
 
#IF 0                       '* metastatement defines (e.g. comment) section for compiler to ignore
' sample data for ltest.dat
 
11
14,61
17,24
24,65
25,69
27,54
33,93
34,17
37,89
40,100
41,90
42,97
 
#ENDIF                      '*

[Mike Hounsome]

Thanks for the latest lesson, Dave! I like the rotated font and the correct position of the Xs and the click on the screen is a nice demonstration which I may well use in other programs but it is not necessary in this one. I've changed the 'LOCAL' statements to split the integers from the reals, so that x,y,xmax and ymax are double precision as they are rarely integers in real life - OK, in the test data set they are integers but usually they would not be. The main problem now is to make the program work for all conceivable data sets. I tried it with the same data except that I moved the decimal point one place to the left in all the X values and the axis scaling and point setting went haywire. As I said in my last message it's the scaling to accommodate all conceivable data that's the problem. I solved it in my TurboBasic programs but I'm having difficulty in seeing how to do it in PBCC. In any case, in my TurboBasic programs it always resulted in messy axis divisions and I'm hopeful that in PBCC I can tidy that up. I hope that you don't mind spending time helping me on this - just let me know when you get bored with it. You've already given me some excellent pointers and I'm very grateful.

Mike

[Dave Biggs]

Not bored yet

What's needed are general algorithms to work out the range of data and appropriate marks and labels on the axes. Somewhat dependant on the actual data to be plotted of course.

This is what I have so far..

' Determine range of values to be plotted and axes required
 FOR r = 1 TO n                                    ' read data -> array (check data range)
  INPUT#1, a(r, 1), a(r, 2)
  xmax = Max(a(r, 1), xmax)                           ' note max & min values
    ymax = Max(a(r, 2), ymax)
    xmin = IIF(xmin > 0, Min(a(r, 1), xmin), a(1,1))    ' initially set min to first value
    ymin = IIF(ymin > 0, Min(a(r, 2), ymin), a(1,2))    ' update in subsequent loops
 NEXT
  PRINT "x" xmin "-" xmax, "y" ymin "-" ymax
 
  xmin = IIF(xmin > 10, Fix (xmin/10)*10,  Fix(xmin))   ' round down minimum values &
  xmax = IIF(xmax > 10, Ceil(xmax/10)*10, Ceil(xmax))   ' round up maximums for scale ranges
  ymin = IIF(ymin > 10, Fix (ymin/10)*10,  Fix(ymin))
  ymax = IIF(ymax > 10, Ceil(ymax/10)*10, Ceil(ymax))
  PRINT "x scale" xmin "-" xmax
  PRINT "y scale" ymin "-" ymax
 
  ' To Do: 
  ' calculate mark spacing based on data range / values
  ' ..divide scale by .5, 5, 50 bigger marks at MOD 1, 10, 100 ?
 
  ' draw axes marks, labels
 
  ' GRAPHIC SET CLIP (margins to set aside area for plotting)
  ' .. ~ 70 pixels on left and bottom, 30 at top for Title, 60 on the right for balance?
 
  ' GRAPHIC SCALE (xmin, ymin) - (xmax, ymax)  ' set custom coordinates for direct plotting of points
 
  ' GRAPHIC PRINT points..
'------------------/
 
'Sample data, results:
x 1.4 - 4.2   y 1.7 - 10         x 14 - 42     y 17 - 100
 
x scale 1 - 5                    x scale 10 - 50
y scale 1 - 10                   y scale 10 - 100
 1.4           6.1                14            61
 1.7           2.4                17            24
 2.4           6.5                24            65
 2.5           6.9                25            69
 2.7           5.4                27            54
 3.3           9.3                33            93
 3.4           1.7                34            17
 3.7           8.9                37            89
 4             10                 40            100
 4.1           9                  41            90
 4.2           9.7                42            97

[Dave Biggs]

Took that forward a little in the code below but it's not such a 'simple scatterplot' anymore

Seems that the trick will be finding a method of analysing the data to deciding what start / stop / interval markers to use.

I've tried to make a generic solution below and it kind of works with the three data sets listed at the end of the source. (Well ok that's not 'all conceivable data sets' but it's heading in that direction )

PB's GRAPHIC SCALE statement makes plotting the data a breeze but actually drawing the axes, marks and labels consistently is a bit trickier.
Use of the new GRAPHIC Functions like GRAPHIC(CANVAS.X) and GRAPHIC(CELL.SIZE.X) helps a lot there as they are scaled along with the window when a different data set is loaded.

'PBCC6 program
#DIM ALL
 
FUNCTION PBMAIN () AS LONG
 LOCAL hBmp, n, hFont1, hFont2, Clk AS LONG
 LOCAL r, x, y, xmax, ymax, xmin, ymin, xmark, ymark AS SINGLE
 LOCAL lm, tm, rm, bm AS SINGLE                           ' margins
 LOCAL slm, stm, srm, sbm AS SINGLE                       ' scaled margins
 LOCAL file, b, xaxis, yaxis, sKey AS STRING
 
  FONT NEW "Lucida Console", 10, 0, 0, 0, 0 TO hFont1     ' set up fonts to be used later
  FONT NEW "Lucida Console", 10, 0, 0, 0, 900 TO hFont2   ' rotated font (needs to be true type)
  CONSOLE SET LOC 1, 1
  CONSOLE SET SCREEN 20, 30
 
  file  = "ltest.dat"                                     ' see example data at end of source
  b     = "Title that is quite long in the scheme of things"
  xaxis = "X-Axis"
  yaxis = "Y-Axis"
 
  lm = 70 : rm = 70 : tm = 40 : bm = 70                   ' Margins (pixels). Space for labels etc
 
  OPEN file$ FOR INPUT AS #1
    INPUT#1, n
    DIM a(1 TO n, 1 TO 2) AS DOUBLE                       ' Note most Graphic sizes etc are single.
 
    GRAPHIC WINDOW "test", 300, 300, 800, 500 TO hBmp&
    GRAPHIC ATTACH hBmp&, 0
    GRAPHIC CLEAR %WHITE
    GRAPHIC COLOR %BLACK, %WHITE
 
    FOR r = 1 TO n                                        ' read data -> array (check data range)
      INPUT#1, a(r, 1), a(r, 2)
      xmax = MAX(a(r, 1), xmax)                           ' take note of max & min values
      ymax = MAX(a(r, 2), ymax)
      xmin = IIF(xmin > 0, MIN(a(r, 1), xmin), a(1,1))    ' initially set min to first value
      ymin = IIF(ymin > 0, MIN(a(r, 2), ymin), a(1,2))    ' update in subsequent loops
    NEXT
 
    PRINT "x" xmin "-" xmax, "y" ymin "-" ymax
    xmin = IIF(xmin > 10, FIX (xmin/10)*10,  FIX(xmin))   ' round down minimum values &
    xmax = IIF(xmax > 10, CEIL(xmax/10)*10, CEIL(xmax))   ' round up maximums for scale ranges
    ymin = IIF(ymin > 10, FIX (ymin/10)*10,  FIX(ymin))
    ymax = IIF(ymax > 10, CEIL(ymax/10)*10, CEIL(ymax))
    PRINT "x scale" xmin "-" xmax
    PRINT "y scale" ymin "-" ymax
 
    ' Calc scaled margins
    slm = lm * (xmax-xmin)/(GRAPHIC(CANVAS.X) - lm - rm) : srm = rm * (xmax-xmin)/(GRAPHIC(CANVAS.X) - lm - rm)
    stm = tm * (ymax-ymin)/(GRAPHIC(CANVAS.Y) - tm - bm) : sbm = bm * (ymax-ymin)/(GRAPHIC(CANVAS.Y) - tm - bm)
    ' PRINT "Margins l,r,t,b" Ceil(slm) Ceil(srm) Ceil(stm) Ceil(sbm)
 
    ' calculate mark spacing based on data range / values
    xmark = SWITCH(xmax-xmin =< 10, 0.5, xmax-xmin =< 100, 5, xmax-xmin =< 500, 50, xmax-xmin =< 1000, 100)  'eg
    ymark = SWITCH(ymax-ymin =< 10, 0.5, ymax-ymin =< 100, 5, ymax-ymin =< 500, 50, ymax-ymin =< 1000, 100)
    PRINT "xmark" xmark "ymark" ymark
    ' ToDo? ..align scale with nearest .5, 5, 50 w/ bigger marks at MOD 1, 10, 100 etc??
 
    ' set custom coordinates for direct plotting of points
    GRAPHIC SCALE (xmin-slm, ymax+stm) - (xmax+srm, ymin-sbm)  ' set custom coordinates for direct plotting of points
 
    ' draw axes marks, labels
    GRAPHIC SET FONT hFont1                                 ' set font
    GRAPHIC SET POS (xmax-(xmax-xmin)/2 - GRAPHIC(TEXT.SIZE.X, b$)/2, ymax + stm/2)
    GRAPHIC PRINT b$
    GRAPHIC SET POS (xmax-(xmax-xmin)/2 - GRAPHIC(TEXT.SIZE.X, xaxis$)/2, ymin - sbm/2)
    GRAPHIC PRINT xaxis$                                    ' xaxis label
 
    GRAPHIC LINE (xmin, ymin) - (xmax, ymin)                ' x axis line
 
    FOR r = xmin TO xmax STEP xmark                         ' marks
      GRAPHIC LINE (r, ymin) - (r, ymin-GRAPHIC(CELL.SIZE.Y)/2)
      GRAPHIC SET POS STEP (-GRAPHIC(CELL.SIZE.X)*1.5, -GRAPHIC(CELL.SIZE.X)*5)
    IF xmax < 10 THEN
      GRAPHIC PRINT FORMAT$(r, "0.0")                       ' print scale values
    ELSE
      GRAPHIC PRINT r
    END IF
    NEXT
 
    GRAPHIC SET FONT hFont2                                 ' font2 (rotated font)
    GRAPHIC SET POS (xmin-slm*.9, ymax / 2)
    GRAPHIC PRINT yaxis$                                    ' yaxis label
    GRAPHIC SET FONT hFont1                                 ' back to font1
 
    GRAPHIC LINE (xmin, ymin) - (xmin, ymax)                ' y axis line
 
    FOR r = ymin TO ymax STEP ymark                         ' marks
      GRAPHIC LINE (xmin, r) - (xmin-GRAPHIC(CELL.SIZE.X)/2, r)
      GRAPHIC SET POS STEP (-GRAPHIC(CELL.SIZE.X)*5, GRAPHIC(CELL.SIZE.Y)/2)
      IF ymax =< 10 THEN
        GRAPHIC PRINT FORMAT$(r, "0.0")                     ' print scale values
      ELSE
      GRAPHIC PRINT r
    END IF
    NEXT
 
    ' GRAPHIC PRINT points..
    FOR r = 1 TO n
      x = a(r, 1) - GRAPHIC(CELL.SIZE.X) / 2            ' adjust point positions to suit "X" center
      y = a(r, 2) + GRAPHIC(CELL.SIZE.Y) / 2
      PRINT a(r, 1), a(r, 2)
      GRAPHIC SET POS (x, y)
      GRAPHIC PRINT "X"
 '      GRAPHIC SET PIXEL (a(r, 1),a(r, 2)), %RED         ' check alignment of point mark
      GRAPHIC SET CAPTION "Click screen for values"
    NEXT r
 
  ' Interaction..
    DO WHILE GRAPHIC(DC) <> 0                           ' loop while Graphic Window exists
      GRAPHIC INKEY$ TO sKey                          ' check keyboard input to graphic window
      SLEEP 1
      IF sKey <> "" THEN EXIT LOOP                    ' any key to quit loop (focus goes to console)
 
      GRAPHIC WINDOW CLICK hBmp TO Clk, x, y          ' check if graphic window clicked
 
      IF Clk = 2 THEN                                               ' Double Click
        GRAPHIC SET CAPTION "test"                                  ' clear old pos info
      ELSEIF Clk = 1 THEN                                           ' Single click
        IF xmax < 10 OR ymax < 10 THEN
          GRAPHIC SET CAPTION USING$("x: #.# y: #.#", x, y)         ' show x, y 'click' position
        ELSE
          GRAPHIC SET CAPTION USING$("x: # y: #", x, y)             ' decimal places not needed
        END IF
      END IF
    LOOP
 
    PRINT "Press any key to end."
    CONSOLE SET FOCUS
    WAITKEY$
  CLOSE
 
END FUNCTION
'------------------/
 
#IF 0                       ' * metastatement defines (e.g. comment) section for compiler to ignore
 
' sample data sets for ltest.dat
    11              11          11
    1.4, 6.1        14, 61      140, 610
    1.7, 2.4        17, 24      170, 240
    2.4, 6.5        24, 65      240, 650
    2.5, 6.9        25, 69      250, 690
    2.7, 5.4        27, 54      270, 540
    3.3, 9.3        33, 93      330, 930
    3.4, 1.7        34, 17      340, 170
    3.7, 8.9        37, 89      370, 890
    4.0, 10.0       40, 100     400, 999
    4.1, 9.0        41, 90      410, 900
    4.2, 9.7        42, 97      420, 970
 
#ENDIF

[Manuel Valdes]

Hi,

In the attached ZIP file please find the source code of a simple, auto-scaling, static plotter, the compiled EXE, and a 540 points testing CSV file.
Even though the testing file was made of sequential points, the program accepts scattered points, provided the highest 'y' value is in the last record of the file. Since the code includes just Basic commands, it compiles both in PBCC GW and PBWin.

I think it can be easily modified to fit the intended use.

Regards,

[Mike Hounsome]

That's brilliant, Dave. I will take a day or two to go through your program learning, as I go, because my wife fell and broke her leg the other day and I'm needed to help her get around.

Manuel: thanks for the link but when I try to download plotter.zip all I get is a PHP page. What am I doing wrong?

[Manuel Valdes]

Hi Mike,

Just double Left (not right) click on the ZIP and select the 'Save' Option in the Pop Up Menu.

Regards


Later: In order to be able to download an attachment you must be logged in

[Dave Biggs]

Downloaded OK for me using IE8 (have to be logged in to the site, not just visiting)

Another fine example Manuel, you do good work!

It'll take me a while to work through the source though - I'm renaming the variables as I go to help me to figure out what's being done where!

I can see though that you are scaling the data values before plotting which defintely helps in drawing the axes and positioning other elements on the window, independent of the data values.

I've been making life more difficult by the use of custom coordinates via GRAPHIC SCALE to enable direct plotting of the data without needing to scale the values.

Something I want to investigate is the use of SET CLIP to protect the other information, labels titles etc from the effects of using GRAPHIC SCALE to set up the plotting area... First, though I must finish mining your work to see what I can pinch

Thanks for sharing!

[Manuel Valdes]

Hi Dave,

It's good to learn that the program looks interesting to you. I never miss a post of yours, as I always have learned a lot from them. Sorry for my short nondescriptive variable names, a custom which came from my old TB and PBDOS days.

Since I have a few days left from my vacations, I am right now adding to the program the capability to handle two variables simultaneously, which doesn't look so difficult.

Best regards,

[Mike Hounsome]

Manuel, I've tried double-left click but it just downloads a PHP file. I use Firefox so I tried IE9 but with the same result. I'm also using a download accelerator, so I disabled it and it worked! Thanks.

[Manuel Valdes]

Dual Channel

Hi,

This is a dual channel version. It works OK provided both channels display variables with the same name, and having values in the same order of magnitud. Next step is to add an option for independent names and scaling.

Regards

[Manuel Valdes]

Final Version

Hi,

Final version of Dual Channel Plotter. I hope it can contain some useful ideas for Mike's purposes. I'll appreciate any suggestion, criticism or comment.

Regards,

[Manuel Valdes]

Scalable Single Channel Plotter

This is an scalable parametric version of the code. Using the function keys F2 to F5, it's possible to change the width and height of the GW, along with the graphic itself.

The testing file is now the US Consumer Price Index from Jan 1913 to Dec 2011 (the later is a forecast, since the official one will be available in a couple days)

Regards,

[Mike Hounsome]

Dave, we've been somewhat trumped by Manuel's tour de force! As you say, there's lots there to learn from but for my initial purposes the simple plot that we (well, you) were working on was adequate. All that had to be done was to solve the scaling of the axes and making sure that it coped with whatever numbers (including negative ones) that were thrown at it. I guess that some of the methods used by Manuel could be transferred to the simple plot but I admit that I'm lost in his code - trying run before I can walk in PBCC. I'll persevere and keep looking at his code to see how he scales the axes. Thanks, both of you, for taking up the challenge.