PHOTON HELP                                  Photon Help ----
Help is available under the following headings :-

  BLOCK                    CLEAR                    CLEAR (R)
  COLOUR                   CONTOUR CLEAR            CONTOUR DELETE
  CONTOUR OFF              CONTOUR ON               CONTOURS
  COORDINATES              DASH                     DOMAIN
  DRAW (R)                 DUMP                     DUMP (R)
  END                      ESCAPE                   EXTRAPOLATE
  FILE (R)                 GEOMETRY (*)             GEOMETRY CLEAR
  GEOMETRY DELETE          GEOMETRY OFF             GEOMETRY ON
  GEOMETRY READ            GEOMETRY SAVE            GEOMETRY_CMDS (*)
  GRID CENTRE              GRID CLEAR               GRID DELETE
  GRID HATCH               GRID OFF                 GRID ON
  GRID OUT                 GRIDS                    HATCH
  LIST (R)                 LOG                      MAGNIFY GRID
  MIRROR                   MONOCHROME (R)           NEWS (*)
  NOCLEAR (R)              PAUSE                    PHI
  PICS (*)                 PREFIX_FILE (*)          REDRAW
  REDRAW (R)               REPLAY                   RESET (R)
  ROTATE                   SAVE                     SCALE (R)
  SCREEN                   SENDP                    SENDP (R)
  SET                      SET AXES                 SET BOX
  SET CONTOUR FILL         SET CONTOUR SCALE        SET CONTOUR UNITS
  SET GEOMETRY             SET HOLD                 SET LHAND
  SET ORDER                SET POROSITY             SET PROPERTY
  SET RHAND                SET VECTOR AVERAGE       SET VECTOR BOUNDARY
  SET VECTOR CENTRE        SET VECTOR COMPONENTS    SET VECTOR KEY
  SET VECTOR PHASE         SET VECTOR REFERENCE     SET VECTOR UNITS
  SHIFT (R)                SHOW                     STOP
  STREAM                   STREAM 2DIMENSTION       STREAM 3DIMENSTION
  STREAM CLEAR             STREAM DELETE            STREAM OFF
  STREAM ON                SURFACE CLEAR            SURFACE DELETE
  SURFACE OFF              SURFACE ON               TEXT
  TEXT CLEAR               TEXT COLOUR              TEXT DELETE
  TEXT LIST                TEXT MOVE                TEXT REPLACE
  TEXT SIZE                TEXT UNDERLINE           UMAGNIFY GRID (U)
  UP                       UPAUSE (U)               UREWIND (U)
  USE                      USHIFT (U)               UTEXT (U)
  VECTOR CLEAR             VECTOR DELETE            VECTOR OFF
  VECTOR ON                VECTORS                  VIEW
  WHERE (R)                XYZ                      4VIEW (R)

To get help on any item listed above, when running PHOTON, type the
item name followed by a question mark, e.g. 'CONTOUR OFF ?'. Items
marked with an asterisk (*) give help on selected topics,
and are not PHOTON commands, while items marked (R) refer
to subcommands of the REPLAY command. Commands marked (U)
may only be issued from a USE file.

In help entries, command names are shown thus :-
   CON[tour] ON <element number>
where the minimum abbreviation for the command is shown in
capitals, with the rest of the command in square brackets.
Any abbreviation of the full name down to the minimum will
be accepted. Parameters are shown in angle brackets; the
program will prompt for essential parameters if they are
not given on the command line.