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5.3.2 SVG Animations

SVG  supports  a  number  of  animation  and  interaction  features.  This  example  will  demonstrate  the  use  of  SVG

animations.

The source  for this  example  is in webMathematica/Examples/SVG/NDSolvePlot.jsp. If  you installed

webMathematica  as  described  

above

,  you  should  be  able  to  connect  to  this  JSP  via  http://localhost:8080/web 

Mathematica/Examples/SVG/NDSolvePlot.jsp. (You may have some other URL for accessing your server.)

The source contains an HTML form that sets up a number of input fields to collect the equation, starting and ending

points, as well as initial conditions. These are then fed to a function that solves the differential equation and returns a

plot of the result formatted as SVG. The SVG is then displayed  with the function SVGDisplay, which is defined

in the package MSP SVG . The code, which inserts the plot, is shown below.

MSPBlock[ {$$eqn, $$t0, $$init1, $$init2, $$t1},

svg = NDSolveToSVG[ $$eqn, {$$init1, $$init2}, 

{$$t0,$$t1}] ;

SVGDisplay[ svg, {400, 300}]]

The actual definition of the function that creates the SVG is shown below. This solves the differential equation and

generates  a  plot  of the  result.  It  then generates  Symbolic  XML,  which  represents  the  SVG  of the  result,  using  the

function    XML SVG GraphicsToSymbolicSVG.  Next,  it  finds  the  points  that  represent  the  plot  of  the  result

and uses these to form an SVG animation of a red ball, which moves along these points. This animation is inserted

into the SVG to form a new result, which is returned to be plotted.

 .