The ornamental design for a displayscreen or portion thereof with a graphicaluserinterface for an ink jet printer, as shown and described.
FIG. 1 is a front view of a display screen or portion thereof with a graphical user interface for an ink jet printer according to the design, showing the graphical user interface enlarged and separate for clarity of illustration;
FIG. 2 is another front view of the display screen or portion thereof with a graphical user interface illustrating an example of as applied to an ink jet printer;
FIG. 3 is a rear elevational view of the ink jet printer;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is a right side elevational view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The broken lines within the graphical user interface illustrate portions of the graphical user interface. The broken line showing of the ink jet printer in FIGS. 2-7 illustrates environmental structure. The broken lines form no part of the claimed design.