From bellow text file, read the text file into a python program and group all the words according to their first letter. Represent the groups in form of dictionary. Where the staring alphabet is the "key" and all the words starting with the alphabets are list of "values".
Text file is:
Among other public buildings in a certain town, which for many reason it will be prudent to
refine from mentioning, and to which i will assign no fictitious name, there is one anciently
common to most towns, great or small.
stream = open('file name', 'r')
str = ''
current = ' '
while current != '':
current = stream.read(50)
str += current
words = str.split(' ')
dict = {}
for w in words:
if not w[0] in dict:
dict[w[0]] = [w]
else:
dict[w[0]].append(w)
The dictionary is dict
Related
i can use string.gsub(message, " ")
but it only cuts the words.
i searched on http://lua-users.org/wiki/StringLibraryTutorial but i cant find any solution for this there
how can i save these words into variables?
for example i have message = "fun 1 true enjoy"
and i want variables to have
var level = 1
var good = true
var message = "enjoy"
Use string.match to extract the fields and then convert them to suitable types:
message = "fun 1 true enjoy"
level,good,message = message:match("%S+%s+(%S+)%s+(%S+)%s+(%S+)")
level = tonumber(level)
good = good=="true"
print(level,good,message)
print(type(level),type(good),type(message))
The pattern in match skips the first field and captures the following three fields; fields are separated by whitespace.
i have a text file that contains data in the format YEAR, CITY, COUNTRY. data is written as one YEAR, CITY, COUNTRY per line. eg -:
1896, Athens, Greece
1900, Paris, France
Previously i was using the data hard coded like this
local data = {}
data[1] = { year = 1896, city = "Athens", country = "Greece" }
data[2] = { year = 1900, city = "Paris", country = "France" }
data[3] = { year = 1904, city = "St Louis", country = "USA" }
data[4] = { year = 1908, city = "London", country = "UK" }
data[5] = { year = 1912, city = "Stockholm", country = "Sweden" }
data[6] = { year = 1920, city = "Antwerp", country = "Netherlands" }
Now i need to read the lines from the file and get the values in to the private knowledge base "local data = {} "
Cant figure out how to capture multiple values using a single pattern from the data in the file.
My code so far is
local path = system.pathForFile( "olympicData.txt", system.ResourceDirectory )
-- Open the file handle
local file, errorString = io.open( path, "r" )
if not file then
-- Error occurred; output the cause
print( "File error: " .. errorString )
else
-- Read each line of the file
for line in file:lines() do
local i, value = line:match("%d")
table.insert(data, i)
-- Close the file
io.close(file)
end
file = nil
Given that you read a line like
1896, Athens, Greece
You can simply obtain the desired values using captures.
https://www.lua.org/manual/5.3/manual.html#6.4.1
Captures: A pattern can contain sub-patterns enclosed in parentheses; they describe captures. When a match succeeds, the
substrings of the subject string that match captures are stored
(captured) for future use. Captures are numbered according to their
left parentheses. For instance, in the pattern "(a*(.)%w(%s*))", the
part of the string matching "a*(.)%w(%s*)" is stored as the first
capture (and therefore has number 1); the character matching "." is
captured with number 2, and the part matching "%s*" has number 3.
As a special case, the empty capture () captures the current string
position (a number). For instance, if we apply the pattern "()aa()" on
the string "flaaap", there will be two captures: 3 and 5.
local example = "1896, Athens, Greece"
local year, city, country = example:match("(%d+), (%w+), (%w+)")
print(year, city, country)
What I'm looking for is something like the following, but it only applies to the first find it gets.
str:gsub("1", "")
I'd like it to only delete the first 1 it finds OR just the first word of the string.
How would I go about doing this?
try this:
local str = "234243 232564 se42"
local str, i = str:gsub("1", "",1)
print (str,i)
str = (i>0) and str or str:gsub("^.-%s", "",1)
print (str)
only when there are spaces in the string (more than one word).
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 ...
}
Hi I've got this function in JavaScript:
function blur(data) {
var trimdata = trim(data);
var dataSplit = trimdata.split(" ");
var lastWord = dataSplit.pop();
var toBlur = dataSplit.join(" ");
}
What this does is it take's a string such as "Hello my name is bob" and will return
toBlur = "Hello my name is" and lastWord = "bob"
Is there a way i can re-write this in Lua?
You could use Lua's pattern matching facilities:
function blur(data) do
return string.match(data, "^(.*)[ ][^ ]*$")
end
How does the pattern work?
^ # start matching at the beginning of the string
( # open a capturing group ... what is matched inside will be returned
.* # as many arbitrary characters as possible
) # end of capturing group
[ ] # a single literal space (you could omit the square brackets, but I think
# they increase readability
[^ ] # match anything BUT literal spaces... as many as possible
$ # marks the end of the input string
So [ ][^ ]*$ has to match the last word and the preceding space. Therefore, (.*) will return everything in front of it.
For a more direct translation of your JavaScript, first note that there is no split function in Lua. There is table.concat though, which works like join. Since you have to do the splitting manually, you'll probably use a pattern again:
function blur(data) do
local words = {}
for m in string.gmatch("[^ ]+") do
words[#words+1] = m
end
words[#words] = nil -- pops the last word
return table.concat(words, " ")
end
gmatch does not give you a table right away, but an iterator over all matches instead. So you add them to your own temporary table, and call concat on that. words[#words+1] = ... is a Lua idiom to append an element to the end of an array.