I am trying to match three pieces of data on a line of text in a text file and store them in table elements. Each line looks something like this:
0.277719 0.474610 This
0.474610 0.721241 is
0.721241 1.063209 test
I have a local table to hold the line of text and I am trying to assign the data pieces as follows.
local data = {}
local file = io.open( "audio/audio.txt", "r" )
local i = 1
for line in file:lines() do
data[i] = line
data[i].start, data[i].out, data[i].name = string.match( line, '(%S+)%s*(%S+)%s*(%S+)' )
i = i + 1
end
The data[i] = line part works just fine. The next line does not.
All I get is the following error on the line data[i].start, data[i].out, data[i].name = string.match( line, '(%S+)%s*(%S+)%s*(%S+)' ):
attempt to index field '?' (a string value)
What am I doing wrong?
The error is in the line
data[i] = line
This line makes data[i] a string variable which cannot have other strings indexed to it. Change that line to:
data[i] = {}
and everything works fine.
Related
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'm trying to iterate through a table with a variable amount of elements and get all possible combinations, only using every element one time. I've landed on the solution below.
arr = {"a","b","c","d","e","f"}
function tablelen(table)
local count = 0
for _ in pairs(table) do
count = count + 1
end
return count
end
function spellsub(table,start,offset)
local str = table[start]
for i = start+offset, (tablelen(table)+1)-(start+offset) do
str = str..","..table[i+1]
end
return str
end
print(spellsub(arr,1,2)) -- Outputs: "a,d,e" correctly
print(spellsub(arr,2,2)) -- Outputs: "b" supposed to be "b,e,f"
I'm still missing some further functions, but I'm getting stuck with my current code. What is it that I'm missing? It prints correctly the first time but not the second?
A solution with a coroutine iterator called recursively:
local wrap, yield = coroutine.wrap, coroutine.yield
-- This function clones the array t and appends the item new to it.
local function append (t, new)
local clone = {}
for _, item in ipairs (t) do
clone [#clone + 1] = item
end
clone [#clone + 1] = new
return clone
end
--[[
Yields combinations of non-repeating items of tbl.
tbl is the source of items,
sub is a combination of items that all yielded combination ought to contain,
min it the minimum key of items that can be added to yielded combinations.
--]]
local function unique_combinations (tbl, sub, min)
sub = sub or {}
min = min or 1
return wrap (function ()
if #sub > 0 then
yield (sub) -- yield short combination.
end
if #sub < #tbl then
for i = min, #tbl do -- iterate over longer combinations.
for combo in unique_combinations (tbl, append (sub, tbl [i]), i + 1) do
yield (combo)
end
end
end
end)
end
for combo in unique_combinations {'a', 'b', 'c', 'd', 'e', 'f'} do
print (table.concat (combo, ', '))
end
For a tables with consecutive integer keys starting at 1 like yours you can simply use the length operator #. Your tablelen function is superfluous.
Using table as a local variable name shadows Lua's table library. I suggest you use tbl or some other name that does not prevent you from using table's methods.
The issue with your code can be solved by printing some values for debugging:
local arr = {"a","b","c","d","e","f"}
function spellsub(tbl,start,offset)
local str = tbl[start]
print("first str:", str)
print(string.format("loop from %d to %d", start+offset, #tbl+1-(start+offset)))
for i = start+offset, (#tbl+1)-(start+offset) do
print(string.format("tbl[%d]: %s", i+1, tbl[i+1]))
str = str..","..tbl[i+1]
end
return str
end
print(spellsub(arr,1,2)) -- Outputs: "a,d,e" correctly
print(spellsub(arr,2,2)) -- Outputs: "b" supposed to be "b,e,f"
prints:
first str: a
loop from 3 to 4
tbl[4]: d
tbl[5]: e
a,d,e
first str: b
loop from 4 to 3
b
As you see your second loop does not ran as the start value is already greater than the limit value. Hence you only print the first value b
I don't understand how your code is related to what you want to achieve so I'll leave it up to you to fix it.
I want to use the variable that I passed to a function which contains a file path. However, I don't get it working.
For example, I have a path like "/samba-test/log_gen/log_gen/log_generator" and when I read this path to a variable it doesn't work as expected. Please refer to my explaination in the code. My comments
are tagged with the string "VENK" . Any help would be appreciated.
/* caller */
config_path = "/samba-test/log_gen/log_gen/log_generator"
ReadWrite_Config(config_path)
/*definition*/
def ReadWrite_Timeline(lp_readpath, lp_filterlist):
current_parent_path = lp_readpath
current_search_list = lp_filterlist
print(current_parent_path) >>>>>> VENK - PATH prints fine here as expected <<<<<<<<.
strings_1 = ("2e88422c-4b61-41d7-9cf9-4650edaa4e56", "2017-11-27 16:1")
for index in range(0,3):
print (current_search_list[index])
files=None
filext=[".txt",".log"]
#outputfile = open(wrsReportFileName, "a")
for ext in filext:
print("Current_Parent_Path",current_parent_path ) <<<<<<VENK - Prints as Expected ""
#VENK - The above line prints as ('Current_Parent_Path', '/samba-test/log_gen/log_gen/log_generator') which is expected
#The actual files are inside the 'varlog' where the 'varlog' folder is inside '/samba-test/log_gen/log_gen/log_generator'
#possible problematic line below.
varlogpath = "(current_parent_path/varlog)/*"+ext >>>>>>>>>>> VENK- Unable to find the files if given in this format <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
print("varlogpath",varlogpath) >>>>>>>>>>>> VENK- varlogpath doesn't print as expected <<<<<<<<<<<<<<<<<<<<
#VENK - The above line prints as ('varlogpath', 'current_parent_path/varlog/*.txt') which I feel is problematic.
#VENK - If I give the absolute path as below it works fine
#varlogpath = "/samba-test/log_gen/log_gen/log_generator/varlog/*"+ext
files = glob.glob(varlogpath)
for file in files:
fname_varlog = open(file, 'r')
outputfile.write("\n")
outputfile.write(file)
outputfile.write("\n")
for line in fname_varlog:
#if any(s in line for s in strings):
"""
#s1 searches the mandatory arguments
#s2 searches the optional arguments
"""
if all(s1 in line for s1 in strings_1):
#if all(s1 in line for s1 in strings_1) or all(s2 in line for s2 in strings_2):
#print (file, end="")
outputfile.write(line)
fname_varlog.close()
outputfile.write("\n")
outputfile.write("10.[##### Summary of the Issue #####] -- Enter Data Manually \n")
outputfile.write("\n")
outputfile.close()
#print (ext)
A path join to the variable 'current_parent_path' helped to resolve the problem (like below).
varlogpath = os.path.join(current_parent_path, "*"+ext)
I'm trying to split a string into 2 strings when main string is over 30 chars and separator I wanted to use is a simple space between chars(the last space between words in main string) so it won't cut words. I'm asking you guys for help because I'm not very good with patterns in Lua.
local function split(str, max_line_length)
local lines = {}
local line
str:gsub('(%s*)(%S+)',
function(spc, word)
if not line or #line + #spc + #word > max_line_length then
table.insert(lines, line)
line = word
else
line = line..spc..word
end
end
)
table.insert(lines, line)
return lines
end
local main_string = 'This is very very very very very very long string'
for _, line in ipairs(split(main_string, 20)) do
print(line)
end
-- Output
This is very very
very very very very
long string
If you just want to split the string at the last space between words, try this
s="How to split string by string length and a separator"
a,b=s:match("(.+) (.+)")
print(s)
print(a)
print(b)
What I'm currently trying to do is make a table of email addresses (as keys) that hold person_records (as values). Where the person_record holds 6 or so things in it. The problem I'm getting is that when I try to assign the email address as a key to a table it complains and says table index is nil... This is what I have so far:
random_record = split(line, ",")
person_record = {first_name = random_record[1], last_name = random_record[2], email_address = random_record[3], street_address = random_record[4], city = random_record[5], state = random_record[6]}
email_table[person_record.email_address] = person_record
I wrote my own split function that basically takes a line of input and pulls out the 6 comma seperated values and stores them in a table (random_record)
I get an error when I try to say email_table[person_record.email_address] = person_record.
But when I print out person_record.email_address it's NOT nil, it prints out the string I stored in it.. I'm so confused.
function split(str, pat)
local t = {} -- NOTE: use {n = 0} in Lua-5.0
local fpat = "(.-)" .. pat
local last_end = 1
local s, e, cap = str:find(fpat, 1)
while s do
if s ~= 1 or cap ~= "" then
table.insert(t,cap)
end
last_end = e+1
s, e, cap = str:find(fpat, last_end)
end
if last_end <= #str then
cap = str:sub(last_end)
table.insert(t, cap)
end
return t
end
The following code is copy and pasted from your example and runs just fine:
email_table = {}
random_record = {"first", "second", "third"}
person_record = {first_name = random_record[1], last_name = random_record[1], email_address = random_record[1]}
email_table[person_record.email_address] = person_record
So your problem is in your split function.
BTW, Lua doesn't have "hashtables". It simply has "tables" which store key/value pairs. Whether these happen to use hashes or not is an implementation detail.
It looks like you iterating over some lines that have comma-separated data.
Looking at your split function, it stops as soon as there's no more separator (,) symbols in particular line to find. So feeding it anything with less than 3 ,-separated fields (for very common example: an empty line at end of file) will produce a table that doesn't go up to [3]. Addressing any empty table value will return you a nil, so person_record.email_address will be set to nil as well on the 2nd line of your code. Then, when you attempt to use this nil stored in person_record.email_address as an index to email_table in 3rd line, you will get the exact error you've mentioned.