Having used plot to produce a range of graphics, I am now trying to add
extra features interactively to the plots produced computationally i.e.
clicking on the plot working out the co-ordinates and then adding a line or
text to the existing plot without redrawing it. Having I think read the
excellent plot documentation I feel I am still missing something and would
appreciate pointing the right direction.
So my simplistic method is to tie a function to the right mouse button, this
is demonstrated in the routine "testplot_plotspace_mbrdown" in the example
code below. This code draws a plot with a straight line and then when you
right click on the graph it plots a vertical line where you have clicked.
However, this a hack having discovered the variables I need (XMIN, XMAX,
YMIN, YMAX), not from the documentation but from looking at the namespace.
So I have 3 questions:
1 is this a sensible way to do such interactive plotting (simple way),
2 Gxywh, Sxywh etc are well documented in the Wiki under the Plot / Layout
Calculation page is there another similar variable which reports the user
units of the maximum X and Y used in the actual plot as the XRANGE variable
is the range of the data not the range over which the data is plotted.
3 is there a way to swap between YAXIS and Y2AXIS, as I would like to be
able to get x and y user co-ordinates back from either scaling, currently it
appears to lock the axis scaling (ymin, ymax) to the Y2AXIS as the last one
used.
Thanks, Simon
require 'files plot strings jzplot'
TESTPLOT=: 0 : 0
pc testplot;
xywh 0 0 269 222;cc plotspace isigraph;
pas 6 6;pcenter;
rem form end;
)
testplot_run=: 3 : 0
wd TESTPLOT
aa=: conew 'jzplot'
PForm__aa=: 'testplot'
PFormhwnd__aa=: wd 'qhwndp'
PId__aa=: 'plotspace'
wd 'pshow;'
pd__aa (0.2+i.10);i.10
pd__aa 'show'
)
testplot_close=: 3 : 0
wd'pclose'
)
testplot_cancel_button=: 3 : 0
testplot_close''
)
testplot_plotspace_mbrdown=: 3 : 0
NB. Adds a vertical line where the cursor is right clicked
NB. Capture the current system state
tyx=: 0&".,sysdata
NB. Store the co-ordinates of the cursor in screen units
'xscreen yscreen'=: 2{.tyx
NB. Discover the size of the area where the graph is being plotted
'xscreenmin yscreenmin xwidth yheight'=: Gxywh__aa
NB. Simplistically thought that I could get the x and y ranges
NB. from the range of the x and y data
'xmin xmax'=. XRANGE__aa
'ymin ymax'=. YRANGE__aa
NB. The data range is wrong as the plot chooses a more sensible
NB. range for the axes
NB. I found that XMIN and XMAX store the min and max of the X axis
xmin=. XMin__aa
xmax=. XMax__aa
NB. So I can now correctly calculate the x co-ordinate in user units
xuser=: xmin+(xmax-xmin)*(xscreen-xscreenmin)%xwidth
NB. I can do the same for y co-ordinates but only for y2 axis
NB. as YMIN__a and YMAX__a are set to y2, don't know how to get
NB. yaxis values back
NB. yuser=: ymax-(ymax-ymin)*(yscreen-yscreenmin)%yheight
NB.pd__a 'yaxis'
NB. Draw a vertical line where the cursor was pressed
pd__aa (xuser,xuser);ymin,ymax
pd__aa 'show'
)
testplot_run ''
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