Great Circle Distance calculator example (with altitude compensation) Lua

[SimPassion]

Isn't that the same as this function?
https://siminnovations.com/wiki/index.p ... c_distance

Thanks for this, very handy ! Indeed Altitude parameter would be useful too ...

[jph]

Isn't that the same as this function?
https://siminnovations.com/wiki/index.p ... c_distance

Thanks for this, very handy ! Indeed Altitude parameter would be useful too ...

Thank you and you are very welcome GIlles. I think as it currently the most elegant solution with altitude that can also be varied. Everything can be improved of course
Joe

[jph]

Thanks Ralph,
Altitude addition makes a heck of a lot of difference in calcs.
I can easily add the RHUMB option and also the various feet / meters / km / miles options etc if needed as the basic code is sorted.
Without altitude (which we never needed in sailing lol ) it is not as accurate for flight calculation.

One thing I found really useful during this experiment was the use of --[[ and --]] for lua code block comment. I had never previously seen that but searched for answers and eventually came across the --[[ and --]]
Rather nice.

You may well know this but I have not seen it in examples that I have looked at -try the following copy and past into AM

Code: Select all

-- this is a normal simple LUA comment

this is not a comment but will cause errors

--[[
this is a BLOCK comment in LUA. All comments are included in between the markers
So this is still included.
And this.
And even this.
this is how we end the block comment
--]]

x = 5 -- this is code followed by a comment

-- notice the difference ?

--[[ the difference is subtle but
extremely useful
Joe Hanley - 2022
I am sure it is pointed out on the wiki but i have missed it. Now I have found it I love it haha  (as the actress said to the bishop)
--]]

Great find, just noticed the ending tag "--]]" which is not obvious, though indeed logical, having "--" at first then "]]", as we used to rather inverted ones on the usual for example with c++ which is "/*" followed by "*/" and similar in multiple coding languages ...

Yes sir, it is specific, Previously I never found the LUA 'block' comment.. it was a revelation to say the least.
It is so strange that we often miss things that are in front of us.
I love lua, it never ceases to amaze me with its total elegance and its total F&CK ups at the same time .. It really is very very nice though.
Joe

[jph]

Honestly, I wonder how many have found the lua block comment ?

Code: Select all

--[[
text1
text2
text3
text4
--]]

I had never seen it used in ANY previous example with AM



It can definitely be used more in descriptions and details

Joe

[Keith Baxter]

Honestly, I wonder how many have found the lua block comment ?

Code: Select all

--[[
text1
text2
text3
text4
--]]

I had never seen it used in ANY previous example with AM



It can definitely be used more in descriptions and details

Joe

Hi

I have used it often for years.
Did you find it in the commented out text in the clone instrument I posted in the AM4.2 bug thread??

Code: Select all

function CloseGuard(switch, yes)
  local s = gSwitch[switch]
  visible(s.img_closed, yes)
  visible(s.img_open, not yes)
  s.closed = yes
end
-- ====================== operate switches ==================
--[[
---------------------- Gen1 switch ----------------
local gSwitchGen1

function cbSwitchGen1(switch, dir)
  if dir > 0 then
    fs2020_event("ROTOR_BRAKE", 2701)
  else
    fs2020_event("ROTOR_BRAKE", 2702)
  end
end

fs2020_variable_subscribe("L:switch_27_73X", "number", function(v)
  SetSwitchPosition(gSwitchGen1, math.floor(v/50)+1)
end)

gSwitchGen1 = AddVerticalSwitch(105, 301, true, true, true, cbSwitchGen1)
]]

BTW. Just for info. The following is also good, no need for the --]], ]] will do.

Code: Select all

--[[
bla
blaa
]]

This is often used in commenting out blocks of code when debugging. Yes also good for commenting on code as well.

Keith

[jph]

Hi Keith
Sorry but I didnt download the SIFF file. For small pieces of code, such as this, I much prefer the function itself to be embedded where possible so it can be copied and pasted.
But great to hear that you found it too. It had to be there somewhere as every other language I use or have used has a similar option available.
Thanks for the info.
Joe