Some instances of CHARACTER*4 IOPSY2 being compared to truncated strings

Start by checking Fortran character comparison rules and the IOPSY2 definition in DPCOHO.INC. Review the three comparisons in dp16.F and dp32.F, then investigate the assignments in dp1.F and edmai2.F. Done means confirming the intended four-character behavior and correcting any affected cases without changing unrelated logic.

IOPSY2 is defined in DPCOHO.INC as being 4 characters in size:

DPCOHO.INC:      CHARACTER*4 IOPSY2

Most of the checks for the value of IOPSY2 compare the variable to a 4 character constant, like this:

dp14.F:            IF(IOPSY2.EQ.'MAC ')THEN

But there are three instances where IOPSY2 is compared to a value less than 4 characters long, which I believe will prevent the desired .EQ. comparisons from doing what is expected.

dp16.F:        ELSEIF(IOPSY2.EQ.'MAC')THEN
dp16.F:        ELSEIF(IOPSY2.EQ.'MAC')THEN
dp32.F:        ELSEIF(IOPSY2.EQ.'MAC')THEN

There are also three instances where IOPSY2 might be set to a value less than 4 characters long, but I don't know if those are significant:

dp1.F:       IOPSY2='8'
dp1.F:      IOPSY2='8'
edmai2.F:         IOPSY2=' '

My last FORTRAN programming was in the 1980s, so I apologize if I'm misunderstanding how a CHARACTER*4 variable holding a 4 character value would be compared to a 3 character constant. Maybe 3 character constants are automatically padded with a space to be 4 characters in length. If that's the case, please feel free to close this issue with no reply.

Until today, the last time I looked over the DATAPLOT code base was when I did a port of DATAPLOT to a Prime minicomputer for the New York State Agricultural Experiment Station in Geneva, NY. Many of their faculty got much use from DATAPLOT in preparing graphs and charts for publications and presentations. Thank you very much for the large contributions that DATAPLOT made to those faculty's research. And I personally derived much satisfaction in helping the faculty move well beyond character-based plots and charts.