gnuplot get "warning: Number of pixels cannot be factored into integers matching grid." when scale the axis

Question

When I use splot in gnuplot,and scale a axis, I got a warning message"warning: Number of pixels cannot be factored into integers matching grid."

The data is like

5539 07/10/2019 13:13:48.265 3.324788E+0 2.488200E+0 2.177561E+0 2.945671E+0 -42.143070E-3   -1.151566E+0    35  21  0
5540 07/10/2019 13:13:48.265 3.315912E+0 2.479325E+0 2.163098E+0 2.913973E+0 -73.840880E-3   -1.203222E+0    36  21  0
5541 07/10/2019 13:13:48.265 3.322815E+0 2.489515E+0 2.179205E+0 2.938627E+0 -37.447099E-3   -1.145696E+0    37  21  0
5542 07/10/2019 13:13:48.265 3.318213E+0 2.480968E+0 2.162440E+0 2.922191E+0 -67.970915E-3   -1.205570E+0    38  21  0
5543 07/10/2019 13:13:48.265 3.347141E+0 2.507594E+0 2.177890E+0 3.025502E+0 27.122514E-3    -1.150392E+0    39  21  0
5544 07/10/2019 13:13:48.265 3.335307E+0 2.515155E+0 2.165728E+0 2.983238E+0 54.124353E-3    -1.193830E+0    40  21  0
5545 07/10/2019 13:13:48.265 3.336950E+0 2.508580E+0 2.162440E+0 2.989108E+0 30.644493E-3    -1.205570E+0    41  21  0  

When I use

splot "QuadFeildData.Jul.10.2019_13.13.txt" u 9:($10*3+3):($8*10) w image

Everything looks fine.THe figure looks like:

Once I tried to

splot "QuadFeildData.Jul.10.2019_13.13.txt" u ($9):($10*3+3):($8*10) w image

where the column 9 is scaled. THe error message pop out warning: Number of pixels cannot be factored into integers matching grid. N = 5545 K = 3 And no figure plot out.

How could I figure it out? I have to scale all axis.

Answer 1

I believe that error message comes from a bug in gnuplot version 4. The method of handling image data was changed in version 5 and that particular bug is no longer triggered.