Hello I am trying to get some data from a text file and put it into a table.
Im not sure how to add more then one pattern while also doing what I want, I know this pattern by its self %a+ finds letters and %b{} finds brackets, but I am not sure how to combine them together so that I find the letters as a key and the brackets as a value and have them be put into a table that I could use.
text file :
left = {{0,63},{16,63},{32,63},{48,63}}
right = {{0,21},{16,21},{32,21},{48,21}}
up = {{0,42},{16,42},{32,42},{48,42}}
down = {{0,0},{16,0},{32,0},{48,0}}
code:
local function get_animations(file_path)
local animation_table = {}
local file = io.open(file_path,"r")
local contents = file:read("*a")
for k, v in string.gmatch(contents, ("(%a+)=(%b{})")) do -- A gets words and %b{} finds brackets
animation_table[k] = v
print("key : " .. k.. " Value : ".. v)
end
file:close()
end
get_animations("Sprites/Player/MainPlayer.txt")
This is valid Lua code, why not simply execute it?
left = {{0,63},{16,63},{32,63},{48,63}}
right = {{0,21},{16,21},{32,21},{48,21}}
up = {{0,42},{16,42},{32,42},{48,42}}
down = {{0,0},{16,0},{32,0},{48,0}}
If you don't want the data in globals, use the string library to turn it into
return {
left = {{0,63},{16,63},{32,63},{48,63}},
right = {{0,21},{16,21},{32,21},{48,21}},
up = {{0,42},{16,42},{32,42},{48,42}},
down = {{0,0},{16,0},{32,0},{48,0}},
}
befor you execute it.
If you insist on parsing that file you can use a something like this for each line:
local line = "left = {{0,63},{16,63},{32,63},{48,63}}"
print(line:match("^%w+"))
for num1, num2 in a:gmatch("(%d+),(%d+)") do
print(num1, num2)
end
This should be enough to get you started. Of course you wouldn't print those values but put them into a table.
I am using corona (lua) with parse.com and I have hit a problem constructing an $in query using values from another table / array.
My code is a little like this:
local usersToFetch = {}
table.insert( usersToFetch, "KnVvDiV2Cj")
table.insert( usersToFetch, "Paf6LDmykp")
and the working query I want to perform is the following lua table (which will get encoded before heading to parse). As I said, this works when I am hard coding the values as shown
local queryTable = {
["where"] = {
["objectId"] = { ["$in"] = {"KnVvDiV2Cj","Paf6LDmykp" }}
},
["limit"] = 1000
}
My problem is how do I incorporate my 'usersToFetch' table in the above table so that it will work the same as hard coding the values?
I swore I tried that but clearly I did not.. I think that I placed it inside the braces whereas they are not needed which is where I went wrong.
Thanks, hjpotte92 - what you put worked fine but this is my final solution in a single declaration:
Where I was going wrong before was because I had too many braces ["objectId"] = { ["$in"] = { usersToFetch } }
local queryTable = {
["where"] = {
["objectId"] = { ["$in"] = usersToFetch}
},
["limit"] = 1000
}
This is my first attempt to use Lua tables and I'm getting on with it quite well. I'm struggling with one thing though, heres (a small sample of) my table as it currently stands:
objects = {
["1/1/1"] = { tl = 1, startVal = 1, stopVal = 0 },
["1/1/2"] = { tl = 11, startVal = 1, stopVal = 0 },
["1/1/3"] = { tl = 22, startVal = 1, stopVal = 0 },
["1/1/4"] = { tl = 33, startVal = 1, stopVal = 0 },
}
The typical operation of this is that I use the "1/1/1" values as a lookup to the inner tables and then use those values in various functions. This all works well. Now, I need to go the other way, say I have tl = 22 coming in, I want to return the top value ("1/1/3" in this case).
I think I need to do something with the inpairs I keep seeing on the web but I'm struggling to implement. Any help would be massively appreciated.
You can't use ipairs because your table is an associated array not a sequence, so you have to use pairs. Also, there is no search function builtin to Lua, so you have to loop over all items yourself, looking for the right field value:
function findTL(tbl)
for key, data in pairs(tbl) do
if data.tl == tlSearch then
return key
end
end
end
local key = findTL(objects, 22)
If you want something a tad more object-oriented you could do this:
objects.findTL = findTL -- ok because first arg is the table to search
local key = objects:findTL(22)
isn't it better to take the value directly?
objects.1/1/1.tl
I don't know if it will work also with slashes, but if not, you may replace it by 'x' for example. Then it will be:
objects.1x1x1.tl
I would like to get efficient way of working with Strings in Qt. Since I am new in Qt environment.
So What I am doing:
I am loading a text file, and getting each lines.
Each line has text with comma separated.
Line schema:
Fname{limit:list:option}, Lname{limit:list:option} ... etc.
Example:
John{0:0:0}, Lname{0:0:0}
Notes:limit can be 1 or 0 and the same as others.
So I would like to get Fname and get limit,list,option values from {}.
I am thinking to write a code with find { and takes what is inside, by reading symbol by symbol.
What is the efficient way to parse that?
Thanks.
The following snippet will give you Fname and limit,list,option from the first set of brackets. It could be easily updated if you are interested in the Lname set as well.
QFile file("input.txt");
if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
qDebug() << "Failed to open input file.";
QRegularExpression re("(?<name>\\w+)\\{(?<limit>[0-1]):(?<list>[0-1]):(?<option>[0-1])}");
while (!file.atEnd())
{
QString line = file.readLine();
QRegularExpressionMatch match = re.match(line);
QString name = match.captured("name");
int limit = match.captured("limit").toInt();
int list = match.captured("list").toInt();
int option = match.captured("option").toInt();
// Do something with values ...
}
In lua, is there any way to read an interface file to extract name/methods/args?
I have an .idl file like this:
interface
{
name = myInterface,
methods = {
testing = {
resulttype = "double",
args = {{direction = "in",
type = "double"},
}
}
}
This is equal to the code bellow (easier to read):
interface myInterface {
double testing (in double a);
};
I can read file, load as string and parse with gmatch for example to extract information, but is there any easy mode to parse this info?
At the end i want something (a table for example) with the interface name, their methods, result types and args. Just to know the interface that i`m working.
Lua has several facilities to interpret chunks of code. Namely, dofile, loadfile and loadstring. Luckily, your input file is almost valid Lua code (assuming those braces were matched). The only thing that is problematic is interface {.
All of the above functions effectively create a function object with a file's or a string's contents as their code. dofile immediately executes that function, while the others return a function, which you can invoke whenever you like. Therefore, if you're free to change the files, replace interface in the first line with return. Then you can do:
local interface = dofile("input.idl")
And interface will be a nice table, just as you have specified it in the file. If you cannot change those files to your liking, you will have to load the file into the string, perform some string manipulation (specifically, replace the first interface with return) and then use loadstring instead:
io.input("input.idl")
local input = io.read("*all")
input = string.gsub(input, "^interface", "return") -- ^ marks beginning of string
local f = loadstring(input)
local interface = f()
In both cases this is what you will get:
> require"pl.pretty".dump(interface)
{
name = "myInterface",
methods = {
testing = {
args = {
{
type = "double",
direction = "in"
}
},
resulttype = "double"
}
}
}
> print(interface.methods.testing.args[1].type)
double
EDIT:
I just realised, in your example input myInterface is not enclosed in " and therefore not a proper string. Is that also a mistake in your input file or is that what your files actually look like? In the latter case, you would need to change that as well. Lua is not going to complain if it's a name it doesn't know, but you also won't get the field in that case.