configure with pgplot detection now flawed

[teuben]

It should auto-detect pgplot, and if failing, fall back to ps.
If ps or pgplot is set, enforce it. If with-pgplot-prefix=PGPLOT_DIR is set, use that, but fail, if not found.

It seem for both redhat (/usr/share/pgplot) and debian (/usr/lib/pgplot5) the default detections were missing.

We also need defaults for Mac on brew and port.

@ParkerTewell

[jcldc]

I struggled to fix some compilations issues on pgplot, but now it starts to work again !
At least I have xwin driver. It works on linux and mac. All problems came from the changement to gcc10 (see https://gcc.gnu.org/gcc-10/porting_to.html)

Here is a screenshot of pgdemo4 running on Macos (intel) and compiled using gcc-11
I have to figure out how to compile gidriv.f and ppdriv.f and it should be ok for nemo installation

[teuben]

what happened to "brew install pgplot" ?

[jcldc]

Actually it does install/work using macport.
But it does not compile anymore from NEMO installation, neither from Linux or Mac.

[teuben]

Should also add that "giza" is now quite functional, sans the ease of opening different yapp=N/xs windows. --with-yapp=giza would be the configure option.