#!../bltwish

source bltDemo.tcl

option add *graph.elemScaleSymbols true

# test to show spline over-shooting

set tcl_precision 15

# Make and fill small vectors
vector x y
x seq 10 0 -0.5 
y expr sin(x^3)
x expr x*x
x sort y
vector x2 y1 y2

# make and fill (x only) large vectors
x populate x2 10

# natural spline interpolation
spline natural x y x2 y1

# quadratic spline interpolation
spline quadratic x y x2 y2 -error 0.0000005

# make plot
graph .graph 
.graph xaxis configure -title "x^2" 
.graph yaxis configure -title "sin(y^3)"

.graph pen configure activeLine -pixels 5
.graph element create Original -x x -y y \
    -color red4 \
    -fill red \
    -pixels 5 \
    -symbol circle

.graph element create Natural -x x2 -y y1 \
    -color green4 \
    -fill green \
    -pixels 3 \
    -symbol triangle

.graph element create Quadratic -x x2 -y y2 \
    -color blue4 \
    -fill orange2 \
    -pixels 3 \
    -symbol diamond 

table . .graph -fill both

Blt_ZoomStack .graph
Blt_Crosshairs .graph
Blt_ActiveLegend .graph
Blt_ClosestPoint .graph
Blt_PrintKey .graph

