VisIt supports visualization of 1D data, however, in a limited form. For making 1D plots, it is suggested to use the Python w-data library.
Suppose you have data generated by 1D code for a lattice:
# W-DATA 0.2.0
# More information about the WData format see: https://gitlab.fizyka.pw.edu.pl/wtools/wdata/-/wikis/home
nx 128 # lattice
ny 16 # lattice
nz 16 # lattice
dx 1 # spacing
dy 1 # spacing
dz 1 # spacing
datadim 1 # dimension of block size: 1=nx, 2=nx*ny, 3=nx*ny*nz
To open it with VisIt, you need to choose Curve-> operators ->Lineout plot

and next set Lineout attributes, in this case as
To re-adjust the y-axis to the range of data, you will need to Reset plot after drawing it:

