#38 error on use when installed from dnf (fedora 23)

[Fred]

hello
from repo
klatexformula.x86_64 : Application for easy image creating from a LaTeX equation
dnf install OK, first opening OK, then just typing a single letter and trying to latex it make :

gs a terminé avec une erreur (code d'erreur 1). Voici la sortie stderr complète :

GPL Ghostscript 9.20: Unrecoverable error, exit code 1
Et voici la sortie stdout complète :
Error: /undefined in 1,000000
Operand stack:

Execution stack:
   %interp_exit   .runexec2   --nostringval--   --nostringval--   --nostringval--   2   %stopped_push   --nostringval--   --nostringval--   --nostringval--   false   1   %stopped_push   1983   1   3   %oparray_pop   1982   1   3   %oparray_pop   --nostringval--   1966   1   3   %oparray_pop   1852   1   3   %oparray_pop   --nostringval--   %errorexec_pop   .runexec2   --nostringval--   --nostringval--   --nostringval--   2   %stopped_push   --nostringval--
Dictionary stack:
   --dict:1204/1684(ro)(G)--   --dict:0/20(G)--   --dict:83/200(L)--
Current allocation mode is local
Last OS error: Not a directory
Current file position is 25516

my machine is

uname -ar
Linux adt 4.12.13-300.fc26.x86_64 #1 SMP Thu Sep 14 16:00:38 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux

thankx !!
Fred