How can I change the decimal separator for my locale?

Copied /usr/share/i18n/locales/sv_SE to .../sv_SE_std-comma
Then edited .../sv_SE 'in place' and copied to .../sv_SE_dp

$ diff -u2 /usr/share/i18n/locales/sv_SE_dp /usr/share/i18n/locales/sv_SE_std-comma 
--- /usr/share/i18n/locales/sv_SE_dp    2020-12-30 21:06:07.959649184 +0100
+++ /usr/share/i18n/locales/sv_SE_std-comma 2020-12-30 19:21:36.726778749 +0100
@@ -196,6 +196,6 @@
 
 LC_NUMERIC
-decimal_point           "."
-thousands_sep           " "
+decimal_point           ","
+thousands_sep           ""
 grouping                3;3
 END LC_NUMERIC

$ sudo locale-gen 
Generating locales (this might take a while)...
- - - 8<---
  sv_SE.UTF-8... done
Generation complete.

$ locale -k LC_NUMERIC
decimal_point="."
thousands_sep=" "
grouping=3;3
numeric-decimal-point-wc=46
numeric-thousands-sep-wc=32
numeric-codeset="UTF-8"

$ 

Now LibreOffice Calc accepts numbers with decimal point,
entered with a deci-point from the numeric keypad Del/,-key

Nice!