[VCLab-Main] [Software][HotEqn][Interactive Equations]

Interactive Equations

dHotEqn is able to replace variables in a given equation by the corresponding right side of other equations located in any applet on the same page. A combination of this mechanism can be of great help in the understanding of mathematical problems since the flow of information and data can be viewed immediately.


Click twice on (eqn3) to see dynamic data exchange.
First use the left mouse button then use the right mouse button.
Also try to drag the mouse and inspect the Java Console.

The example on the left side shows 3 different equations where each one is located in a separate applet window (eqn1, eqn2, eqn3). Equation (eqn3) depends on the variables x and y.

By clicking with the left mouse button on the applet window of equation (eqn3) both x and y are replaced by the corresponding right sides of equations (eqn1) and (eqn2).

On a second click, the variable x coming from equation (eqn2) will be substituted again.

By clicking with the right mouse button on the applet window of equation (eqn3) the original equation is shown again.

Let's have a look at the HTML code of this example.

    <applet code=dHotEqn.class height=40 width=60 name=eqn1 align=absmiddle>
    <param  name="leftside"    value="x">
    <param  name="rightside"   value="\fgcolor{ff0000}{\sqrt{\frac{3}{5}}}">
    <param  name="editable"    value="true">
    <applet code=dHotEqn.class height=70 width=150 name=eqn2 align=absmiddle>
    <param  name="leftside"    value="y">
    <param  name="rightside"   value="\fgcolor{004000}{\sum_{i=0}^{5}\sin\left(x+2\right)^i}">
    <param  name="editable"    value="true">
    <applet code=dHotEqn.class height=80 width=250 name=eqn3 align=absmiddle>
    <param  name="equation"    value="z=\sqrt{3\ast x+4}-\frac{4}{y}">
    <param  name="prev0"       value="eqn1">
    <param  name="prev1"       value="eqn2">
    <param  name="editable"    value="true">


The first two applets (eqn1) and (eqn2) have the leftside and rightside parameters to define a valid equation. dHotEqn combines both sides and adds a "=" sign between both terms.

The third equation (eqn3) uses the prev0 and prev1 parameters to determine the equations where the missing variables are located. The data are transferred using the browsers applet context. For security reasons this mechanism does not work between different frames.

[VCLab-Main] [Software][HotEqn][Interactive Equations]

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