I want to take 5 inputs like
1 2 3 4 5
using a for loop that runs 5 times.
stdin.readLineSync() takes the whitespace as an input and continues until I press ENTER but I want it to separate by whitespace like scanf in C.
How can I do that ?
After you read a line with readLineSync(), you can split it by whitespace with String.split and then iterate over the tokens:
var line = stdin.readLineSync();
var tokens = line.split(RegExp(r'\s+'));
Related
how can I extract a few words separated by symbols in a string so that nothing is extracted if the symbols change?
for example I wrote this code:
function split(str)
result = {};
for match in string.gmatch(str, "[^%<%|:%,%FS:%>,%s]+" ) do
table.insert(result, match);
end
return result
end
--------------------------Example--------------------------------------------
str = "<busy|MPos:-750.222,900.853,1450.808|FS:2,10>"
my_status={}
status=split(str)
for key, value in pairs(status) do
table.insert(my_status,value)
end
print(my_status[1]) --
print(my_status[2]) --
print(my_status[3]) --
print(my_status[4]) --
print(my_status[5]) --
print(my_status[6]) --
print(my_status[7]) --
output :
busy
MPos
-750.222
900.853
1450.808
2
10
This code works fine, but if the characters and text in the str string change, the extraction is still done, which I do not want to be.
If the string change to
str = "Hello stack overFlow"
Output:
Hello
stack
over
low
nil
nil
nil
In other words, I only want to extract if the string is in this format: "<busy|MPos:-750.222,900.853,1450.808|FS:2,10>"
In lua patterns, you can use captures, which are perfect for things like this. I use something like the following:
--------------------------Example--------------------------------------------
str = "<busy|MPos:-750.222,900.853,1450.808|FS:2,10>"
local status, mpos1, mpos2, mpos3, fs1, fs2 = string.match(str, "%<(%w+)%|MPos:(%--%d+%.%d+),(%--%d+%.%d+),(%--%d+%.%d+)%|FS:(%d+),(%d+)%>")
print(status, mpos1, mpos2, mpos3, fs1, fs2)
I use string.match, not string.gmatch here, because we don't have an arbitrary number of entries (if that is the case, you have to have a different approach). Let's break down the pattern: All captures are surrounded by parantheses () and get returned, so there are as many return values as captures. The individual captures are:
the status flag (or whatever that is): busy is a simple word, so we can use the %w character class (alphanumeric characters, maybe %a, only letters would also do). Then apply the + operator (you already know that one). The + is within the capture
the three numbers for the MPos entry each get (%--%d+%.%d+), which looks weird at first. I use % in front of any non-alphanumeric character, since it turns all magic characters (such as + into normal ones). - is a magic character, so it is required here to match a literal -, but lua allows to put that in front of any non-alphanumerical character, which I do. So the minus is optional, so the capture starts with %-- which is one or zero repetitions (- operator) of a literal - (%-). Then I just match two integers separated by a dot (%d is a digit, %. matches a literal dot). We do this three times, separated by a comma (which I don't escape since I'm sure it is not a magical character).
the last entry (FS) works practically the same as the MPos entry
all entries are separated by |, which I simply match with %|
So putting it together:
start of string: %<
status field: (%w+)
separator: %|
MPos (three numbers): MPos:(%--%d+%.%d+),(%--%d+%.%d+),(%--%d+%.%d+)
separator: %|
FS entry (two integers): FS:(%d+),(%d+)
end of string: %>
With this approach you have the data in local variables with sensible names, which you can then put into a table (for example).
If the match failes (for instance, when you use "Hello stack overFlow"), nil` is returned, which can simply be checked for (you could check any of the local variables, but it is common to check the first one.
I've a string like this "some text !11.22.33" and when i call
"some text !11.22.33".scan(/!(\w+)/)[0].join.to_s
it returns only "11".
I want to return "11.22.33" so scan function has to skip dot and take all the string. How i can do that?
If your string is always in this format, just use
"some text !11.22.33".partition('!').last
For a regex approach, you may use matching with capturing:
"some text !11.22.33"[/!([\d.]+)/, 1]
See the Ruby demo
Details:
! - a literal ! symbol
([\d.]+) - Capturing group 1: one or more digits or dots
The 1 argument tells Ruby to output only the captured value
An alternative regex is /!(\d+(?:\.\d+)*)/ that will capture 1+ digits and then 0 or more sequences of a . and 1+ digits (so, if there is a trailing dot, it won't be captured).
I have a string of “words”, like this: fIsh mOuntain rIver. The words are separated by a space, and I added spaces to the beginning and ending of the string to simplify the definition of a “word”.
I need to replace any words containing A, B, or C, with 1, any words containing X, Y, or Z with 2, and all remaining words with 3, e.g.:
the CAT ATE the Xylophone
First, replacing words containing A, B, or C with 1, the string becomes:
the 1 1 the Xylophone
Next, replacing words containing X, Y, or Z with 2, the string becomes:
the 1 1 the 2
Finally, it replaces all remaining words with 3, e.g.:
3 1 1 3 2
The final output is a string containing only numbers, with spaces between.
The words might contain any kind of symbols, e.g.: $5鱼fish can be a word. The only feature defining the beginning and ending of words is the spaces.
The matches are found in order, such that words which might possibly contain two matches, e.g. ZebrA, is simply replaced with 1.
The string is in UTF-8.
How can I replace all of the words containing these particular characters with numbers, and finally replace all remaining words with 3?
Try the following code:
function replace(str)
return (str:gsub("%S+", function(word)
if word:match("[ABC]") then return 1 end
if word:match("[XYZ]") then return 2 end
return 3
end))
end
print(replace("the CAT ATE the Xylophone")) --> 3 1 1 3 2
The slnunicode module provides UTF-8 string functions.
The gsub function/method in Lua is used to replace strings and to check out how times a string is found inside a string. gsub(string old, string from, string to)
local str = "Hello, world!"
newStr, recursions = str:gsub("Hello", "Bye"))
print(newStr, recursions)
Bye, world! 1
newStr being "Bye, world!" because from was change to to and recursions being 1 because "Hello" (from) was only founds once in str.
I've been given a large file with a funny CSV format to parse into a database.
The separator character is a semicolon (;). If one of the fields contains a semicolon it is "escaped" by wrapping it in doublequotes, like this ";".
I have been assured that there will never be two adjacent fields with trailing/ leading doublequotes, so this format should technically be ok.
Now, for parsing it in VBScript I was thinking of
Replacing each instance of ";" with a GUID,
Splitting the line into an array by semicolon,
Running back through the array, replacing the GUIDs with ";"
It seems to be the quickest way. Is there a better way? I guess I could use substrings but this method seems to be acceptable...
Your method sounds fine with the caveat that there's absolutely no possibility that your GUID will occur in the text itself.
On approach I've used for this type of data before is to just split on the semi-colons regardless then, if two adjacent fields end and start with a quote, combine them.
For example:
Pax;is;a;good;guy";" so;says;his;wife.
becomes:
0 Pax
1 is
2 a
3 good
4 guy"
5 " so
6 says
7 his
8 wife.
Then, when you discover that fields 4 and 5 end and start (respectively) with a quote, you combine them by replacing the field 4 closing quote with a semicolon and removing the field 5 opening quote (and joining them of course).
0 Pax
1 is
2 a
3 good
4 guy; so
5 says
6 his
7 wife.
In pseudo-code, given:
input: A string, first character is input[0]; last
character is input[length]. Further, assume one dummy
character, input[length+1]. It can be anything except
; and ". This string is one line of the "CSV" file.
length: positive integer, number of characters in input
Do this:
set start = 0
if input[0] = ';':
you have a blank field in the beginning; do whatever with it
set start = 2
endif
for each c between 1 and length:
next iteration unless string[c] = ';'
if input[c-1] ≠ '"' or input[c+1] ≠ '"': // test for escape sequence ";"
found field consting of half-open range [start,c); do whatever
with it. Note that in the case of empty fields, start≥c, leaving
an empty range
set start = c+1
endif
end foreach
Untested, of course. Debugging code like this is always fun….
The special case of input[0] is to make sure we don't ever look at input[-1]. If you can make input[-1] safe, then you can get rid of that special case. You can also put a dummy character in input[0] and then start your data—and your parsing—from input[1].
One option would be to find instances of the regex:
[^"];[^"]
and then break the string apart with substring:
List<string> ret = new List<string>();
Regex r = new Regex(#"[^""];[^""]");
Match m;
while((m = r.Match(line)).Success)
{
ret.Add(line.Substring(0,m.Index + 1);
line = line.Substring(m.Index + 2);
}
(Sorry about the C#, I don't known VBScript)
Using quotes is normal for .csv files. If you have quotes in the field then you may see opening and closing and the embedded quote all strung together two or three in a row.
If you're using SQL Server you could try using T-SQL to handle everything for you.
SELECT * INTO MyTable FROM OPENDATASOURCE('Microsoft.JET.OLEDB.4.0',
'Data Source=F:\MyDirectory;Extended Properties="text;HDR=No"')...
[MyCsvFile#csv]
That will create and populate "MyTable". Read more on this subject here on SO.
I would recommend using RegEx to break up the strings.
Find every ';' that is not a part of
";" and change it to something else
that does not appear in your fields.
Then go through and replace ";" with ;
Now you have your fields with the correct data.
Most importers can swap out separator characters pretty easily.
This is basically your GUID idea. Just make sure the GUID is unique to your file before you start and you will be fine. I tend to start using 'Z'. After enough 'Z's, you will be unique (sometimes as few as 1-3 will do).
Jacob
I have a file with several thousand rows and several columns separated with tabs What I'd like to do is loop through each individually, Drop the columns into an array so that I can place them in another application individually, then move onto the next line. Unfortunately I got about as far as this:
Open mytextfile.txt For Input As #FileHandle
Do While Not EOF(FileHandle)
Line Input #FileHandle, IndividualLine
StringToBreakup = IndividualLine
Loop
So how would I go about breaking individual line up into an array
Dim str() as String
Open mytextfile.txt For Input As #FileHandle
Do While Not EOF(FileHandle)
Line Input #FileHandle, IndividualLine
str = Split(IndividualLine, vbTab)
Debug.Print str(0) 'First array element
Loop
To clarify: I would avoid the use of Variants and use vbTab.
Use the split command
Dim StringArray as Variant
Open mytextfile.txt For Input As #FileHandle
Do While Not EOF(FileHandle)
Line Input #FileHandle, IndividualLine
StringToBreakup = IndividualLine
StringArray = Split(StringToBreakup, CHR(9))
Process array here...
Loop