#42

i of course grabbed that last night :slight_smile:
Norns is 32 bit dev?

pp

#43

er, not sure i understand the question. the norns hardware (CM3) is an arm64 platform, and the lua on norns uses the default 64-bit precision for numbers. (this is a compile-time option for the Lua language.)

#45

should the lua stuff on windows be /Program Files [64bit] or /Program Files (x86)

i think i just dont grasp it yet. I need a new language and i need some basic TOOTs we used to call them in Csound olden days

some Lua Toots :slight_smile:

I am going to pull some SuperCollider Files too from the vaults and hopefully get inspired

#46

Does anyone know if integer divide // is faster than the regular / operator on integers? How can I check the implementation or test run speeds?

#47

no, itā€™s not really an optimization device. use floor division (//) when you want floor(a/b) and use division (/) when you want a/b. standard division always returns a float even if the operands are both integer, and vice versa for floor division.

How can I check the implementation

look at the lua source

this tells us, if the operands are both int, luaV_div is called, otherwise you get some macros, after which unwrapping are simply the C expression floor(a/b)

or test run speeds?

check system time, perform many calculations, check time again.

but my advice is to not waste your time with this. lua is fast for a scripting language but itā€™s not C or ASM. each operation in lua involves many processor instructions as it performs type checking, handles edge cases &c. the actual arithmetic is going to be done in a single instruction and is relatively insignificant. if you need to rapidly perform thousands or millions of calculations then maybe doing it in lua is not the way to go.

1 Like
#48

A bit of an aside, but: is there any reason why Lua on the norns is 5.1.5 (dated Feb 2012)? Latest official release is 5.3.5.

#49

noā€¦ thatā€™s weird. it must be whatever comes with raspbian stretch.

the lua environment that actually runs norns scripts is 5.3 (we just link from liblua5.3-dev)

#50

Oh - it never occurred to me that the norms environment would be running something other than the default /usr/bin/lua. Does the 5.3 installation have a command line component? I want something for running unit tests. (Matron might do that for me, but Iā€™m not seeing any summary output from them.)

#51

I ran into this the other day when trying to run some unit tests. The lua 5.3.x command line is available as a separate package (which is not installed in the norns image by default). I did the following on my dev device.

  • sudo apt-get install lua5.3
  • Install luarocks
  • luarocks install luaunit

One has to invoke lua5.3 explicitly to get the newer runtime.

1 Like
#52

Thanks for that - I was wondering about the wisdom of doing an apt-get install - though as a Mac user I suppose I could just SMB-mount the norns drive and run a Homebrew-installed Lua from macOS insteadā€¦

#53

I find it useful to have a functional environment on both the device and my laptop. When working on particularly ambitious projects I separate code into norns specific and platform independent so that a subset of the tests can be run off device.

#54

Quite so. The lower-level grid driving code probably wonā€™t get added to the tests, but Iā€™ll keep that as simple as possible. The complex higher level stuff is (or will be) pure Lua, and I can probably mock the lower-level stuff for testing if I need to.

#55

out of curiosity have any first time programmers had success reading through Programming in Lua?

I thought it was pretty well written but I had prior programming experience before going into it

2 Likes
#56

Nope, might try gradually

seems comprehensive (and therefore somewhat daunting)

2 Likes
#57

same. looks like a great resource, but today i was reading microsound, then started max/msp free trial, and then tried reading this and it was a bit of an overload lol :face_with_head_bandage: thanks 4 sharing tho ~

1 Like
#58

yea, fair enough, i was relying on it more for the advanced topics but the starter pages are probably a little too dense

#59

how do people feel about the english language syntax in lua (i.e. if then end do) ? as an experienced programmer itā€™s a minor annoyance, but for newcomers, Iā€™m curious if itā€™s helped anyone come to grips with the logical operations or made code more readable compared to c-style:

if (true) {
    thing()
} else {
    otherthing()
}

technically lua was my first programming language and my intro to these concepts, but I do not remember back that far : )

#60

I forget the then almost every time

1 Like
#61

donā€™t get me started on if do

#62

the thing that bothers me is the other way round, writing some javascript after a session of lua writing adding in then from muscle memory constantly