Question: How to pass the abscissa of a node to the first 2 mandatory arguments of `\psplot`? I have tried `\psGetCenterNode` but it produced an error in PS interpreting phase.

```
\documentclass[border=12pt,pstricks]{standalone}
\usepackage{pstricks-add,pst-eucl}

\def\foo{x \psPi\space div 180 mul sin}
\def\goo{x \psPi\space div 180 mul cos}
\def\hoo{x}
\begin{document}
\begin{pspicture}[showgrid=bottom](0,-2)(5,2)
    \psplot[linecolor=red]{0}{4.5}{\foo}
    \psplot[linecolor=blue]{0}{4.5}{\goo}
    \pstInterFF{\foo}{\goo}{0}{A}
    \pstInterFF{\foo}{\goo}{4}{B}
    %\psplot{A.x}{B.x}{\hoo} <== does NOT work!
\end{pspicture}
\end{document}

```

Answer: 
```
\documentclass{article}
\usepackage{pst-plot,pst-eucl}

\def\foo{x RadtoDeg sin}
\def\goo{x RadtoDeg cos}
\def\hoo{x}
\begin{document}
\begin{pspicture}[showgrid=bottom](0,-2)(5,2)
    \psplot[linecolor=red]{0}{4.5}{\foo}
    \psplot[linecolor=blue]{0}{4.5}{\goo}
    \pstInterFF{\foo}{\goo}{0}{A}
    \pstInterFF{\foo}{\goo}{4}{B}
    \psplot{\psGetNodeCenter{A} A.x}{\psGetNodeCenter{B} B.x}{\hoo}
\end{pspicture}

\end{document}

```

![enter image description here](https://i.stack.imgur.com/MmqfT.png)
Just another method.

```
\documentclass[border=12pt,pstricks]{standalone}
\usepackage{pst-eucl,pst-plot}

\def\foo{(sin(x))}
\def\goo{(cos(x))}
\def\hoo{(x)}

\pstVerb{/I2P {AlgParser cvx exec} def}
\begin{document}
\begin{pspicture}[showgrid=bottom,algebraic,saveNodeCoors](0,-2)(5,2)
    \psplot[linecolor=red]{0}{4.5}{\foo}
    \psplot[linecolor=blue]{0}{4.5}{\goo}
    \pstInterFF{\foo I2P}{\goo I2P}{0}{A}
    \pstInterFF{\foo I2P}{\goo  I2P}{4}{B}
    \psplot{N-A.x}{N-B.x}{\hoo}
\end{pspicture}
\end{document}

```