Updated 2010-08-13 19:43:55 by AKgnome

the graph widget can even be used for excessive amounts of data:

 package require BLT
 namespace import ::blt::vector
 namespace import ::blt::graph

 # create a graph widget and show a grid
 graph .g ; pack .g -expand 1 -fill both
 .g grid configure -hide no
 # enable zooming
 Blt_ZoomStack .g

 set start [ clock  clicks -milliseconds ]
 # create two vectors,
 set ::X [ vector #auto ]
 set ::Y [ vector #auto ]

 # fill one vector for the x axis with 1 million points
 $::X seq 0 1.0e6
 # fill one vector for the y axis with a sine + noise
 $::Y expr "sin($::X/1e5) +(0.05*(random($::X)-0.5))"

 # create one element with data for the x and y axis, no dots
 .g element create Wave1 -xdata $::X -ydata $::Y -symbol none

 set stop [ clock clicks -milliseconds ]
 puts time_blt_vector_example:[expr ($stop - $start)/ 1000.0]

AET 24jan07 Erm . . .it chokes on the random() call. I'm using dqkit (tcl8.4.5). Complains
  can't find vector "random"

Tried srand(), same result.

UK pasting this into wish runs without fault. Did you loose the quotes? ... Just tested with kit-8.4.13-build1-linux-x86-STall.bin : no probs

LV I just copy and pasted this example into a text file and ran it against Tcl/Tk 8.4.7 and BLT 3.0. I get this error:
 Error in startup script: can't import command "label": already exists
    while executing
 "namespace import ::blt::*"
    (file "/tmp/samblt.tk" line 5)

Anyone have any idea what might be going wrong?

UK I guess BLT has grown a [label] command? apropos: BLT 3.0 from cvs at sourceforge?