I'm new to LUA but figured out that gsub is a global substitution function and tonumber is a converter function. What I don't understand is how the two functions are used together to produce an encoded string.
I've already tried reading parts of PIL (Programming in Lua) and the reference manual but still, am a bit confused.
local L0_0, L1_1
function L0_0(A0_2)
return (A0_2:gsub("..", function(A0_3)
return string.char((tonumber(A0_3, 16) + 256 - 13 + 255999744) % 256)
end))
end
encodes = L0_0
L0_0 = gg
L0_0 = L0_0.toast
L1_1 = "__loading__\226\128\166"
L0_0(L1_1)
L0_0 = encodes
L1_1 = --"The Encoded String"
L0_0 = L0_0(L1_1)
L1_1 = load
L1_1 = L1_1(L0_0)
pcall(L1_1)
I removed the encoded string where I put the comment because of how long it was. If needed I can upload the encoded string as well.
gsub is being used to get 2 digit sections of A0_2. This means the string A0_3 is a 2 digit hexadecimal number but it is not in a number format so we cannot preform math on the value. A0_3 being a hex number can be inferred based on how tonubmer is used.
tonumber from Lua 5.1 Reference Manual:
Tries to convert its argument to a number. If the argument is already a number or a string convertible to a number, then tonumber returns this number; otherwise, it returns nil.
An optional argument specifies the base to interpret the numeral. The base may be any integer between 2 and 36, inclusive. In bases above 10, the letter 'A' (in either upper or lower case) represents 10, 'B' represents 11, and so forth, with 'Z' representing 35. In base 10 (the default), the number can have a decimal part, as well as an optional exponent part (see §2.1). In other bases, only unsigned integers are accepted.
So tonumber(A0_3, 16) means we are expecting for A0_3 to be a base 16 number (hexadecimal).
Once we have the number value of A0_3 we do some math and finally convert it to a character.
function L0_0(A0_2)
return (A0_2:gsub("..", function(A0_3)
return string.char((tonumber(A0_3, 16) + 256 - 13 + 255999744) % 256)
end))
end
This block of code takes a string of hex digits and converts them into chars. tonumber is being used to allow for the manipulation of the values.
Here is an example of how this works with Hello World:
local str = "Hello World"
local hex_str = ''
for i = 1, #str do
hex_string = hex_string .. string.format("%x", str:byte(i,i))
end
function L0_0(A0_2)
return (A0_2:gsub("..", function(A0_3)
return string.char((tonumber(A0_3, 16) + 256 - 13 + 255999744) % 256)
end))
end
local encoded = L0_0(hex_str)
print(encoded)
Output
;X__bJbe_W
And taking it back to the orginal string:
function decode(A0_2)
return (A0_2:gsub("..", function(A0_3)
return string.char((tonumber(A0_3, 16) + 13) % 256)
end))
end
hex_string = ''
for i = 1, #encoded do
hex_string = hex_string .. string.format("%x", encoded:byte(i,i))
end
print(decode(hex_string))
How can I access the name property of a ProtoField after I declare it?
For example, something along the lines of:
myproto = Proto("myproto", "My Proto")
myproto.fields.foo = ProtoField.int8("myproto.foo", "Foo", base.DEC)
print(myproto.fields.foo.name)
Where I get the output:
Foo
An alternate method that's a bit more terse:
local fieldString = tostring(field)
local i, j = string.find(fieldString, ": .* myproto")
print(string.sub(fieldString, i + 2, j - (1 + string.len("myproto")))
EDIT: Or an even simpler solution that works for any protocol:
local fieldString = tostring(field)
local i, j = string.find(fieldString, ": .* ")
print(string.sub(fieldString, i + 2, j - 1))
Of course the 2nd method only works as long as there are no spaces in the field name. Since that's not necessarily always going to be the case, the 1st method is more robust. Here is the 1st method wrapped up in a function that ought to be usable by any dissector:
-- The field is the field whose name you want to print.
-- The proto is the name of the relevant protocol
function printFieldName(field, protoStr)
local fieldString = tostring(field)
local i, j = string.find(fieldString, ": .* " .. protoStr)
print(string.sub(fieldString, i + 2, j - (1 + string.len(protoStr)))
end
... and here it is in use:
printFieldName(myproto.fields.foo, "myproto")
printFieldName(someproto.fields.bar, "someproto")
Ok, this is janky, and certainly not the 'right' way to do it, but it seems to work.
I discovered this after looking at the output of
print(tostring(myproto.fields.foo))
This seems to spit out the value of each of the members of ProtoField, but I couldn't figure out the correct way to access them. So, instead, I decided to parse the string. This function will return 'Foo', but could be adapted to return the other fields as well.
function getname(field)
--First, convert the field into a string
--this is going to result in a long string with
--a bunch of info we dont need
local fieldString= tostring(field)
-- fieldString looks like:
-- ProtoField(188403): Foo myproto.foo base.DEC 0000000000000000 00000000 (null)
--Split the string on '.' characters
a,b=fieldString:match"([^.]*).(.*)"
--Split the first half of the previous result (a) on ':' characters
a,b=a:match"([^.]*):(.*)"
--At this point, b will equal " Foo myproto"
--and we want to strip out that abreviation "abvr" part
--Count the number of times spaces occur in the string
local spaceCount = select(2, string.gsub(b, " ", ""))
--Declare a counter
local counter = 0
--Declare the name we are going to return
local constructedName = ''
--Step though each word in (b) separated by spaces
for word in b:gmatch("%w+") do
--If we hav reached the last space, go ahead and return
if counter == spaceCount-1 then
return constructedName
end
--Add the current word to our name
constructedName = constructedName .. word .. " "
--Increment counter
counter = counter+1
end
end
I am trying to compare the input string with the strings present in the doc. I am using strcmp for the purpose. These are non-English strings. When the input string is English language, the output is correct. But for any Kannada (non-English language) word the output is the same. I am trying to write a program to check if the word is present in the database. Please guide me in what could be the problem.
The calling function is as below:
str_kan = handles.InputBox.String;
res = strcmp('str_kan','s1.text')
if res == 1 then handles.InputBox.String = string( ' present')
abort
else
handles.InputBox.String = string( 'not present')
abort
end
The whole program is as below:
global s1
f=figure('figure_position',[400,50],'figure_size',[640,480],'auto_resize','on','background',[33],'figure_name','Graphic window number %d','dockable','off','infobar_visible','off','toolbar_visible','off','menubar_visible','off','default_axes','on','visible','off');
handles.dummy = 0;
handles.InputBox=uicontrol(f,'unit','normalized','BackgroundColor',[-1,-1,-1],'Enable','on','FontAngle','normal','FontName','Tunga','FontSize',[12],'FontUnits','points','FontWeight','normal','ForegroundColor',[-1,-1,-1],'HorizontalAlignment','left','ListboxTop',[],'Max',[1],'Min',[0],'Position',[0.0929487,0.6568182,0.4647436,0.1795455],'Relief','default','SliderStep',[0.01,0.1],'String','Enter a Kannada Word','Style','edit','Value',[0],'VerticalAlignment','middle','Visible','on','Tag','InputBox','Callback','')
handles.CheckDB=uicontrol(f,'unit','normalized','BackgroundColor',[-1,-1,-1],'Enable','on','FontAngle','normal','FontName','Tahoma','FontSize',[12],'FontUnits','points','FontWeight','normal','ForegroundColor',[-1,-1,-1],'HorizontalAlignment','center','ListboxTop',[],'Max',[1],'Min',[0],'Position',[0.1025641,0.4636364,0.4567308,0.1204545],'Relief','default','SliderStep',[0.01,0.1],'String','Check','Style','pushbutton','Value',[0],'VerticalAlignment','middle','Visible','on','Tag','CheckDB','Callback','CheckDB_callback(handles)')
f.visible = "on";
function CheckDB_callback(handles)
str_kan = handles.InputBox.String;
res = strcmp('str_kan','s1.text')
if res == 1 then handles.InputBox.String = string( ' present')
abort
else
handles.InputBox.String = string( 'not present')
abort
end
endfunction
Here is an example showing that, in Scilab, strcmp() does support UTF-8 extended characters:
--> strcmp(["aα" "aα" "aβ"], ["aα" "aβ" "aα"])
ans =
0. -1. 1.
The problem in the original posted code is the confusion between literal values as "Hello" and variables names as Hello="my text", as already noted by PTRK.
Using HtmlProvider to access a web-based table sometimes returns a fraction as a string (correct) and, at other times, returns a DateTime (incorrect).
What am I missing?
module Test =
open FSharp.Data
let [<Literal>] url = "https://www.example.com/fractions"
type profile = HtmlProvider<url>
let profile = profile.Load(url)
let [<Literal>] resultFile = #"C:\temp\data\Profile.csv"
let CsvResult =
do
use writer = new StreamWriter(resultFile, false)
writer.WriteLine "\"Date\";\"Fraction\""
for row in profile.Tables.Table1.Rows do
"\"" + row.``Date``.ToString() + "\"" + ";" |> writer.Write
"\"" + row.``Fraction``.ToString() + "\"" + ";" |> writer.WriteLine
writer.Close
let csvResult = CsvResult
Without seeing sample data I can't be 100% certain, but I'm guessing that it's parsing fractions as dates if the numbers involved would be valid dates in the culture you're using: e.g., 1/4 would be a valid date in any culture that uses / as a separator, and would be treated either as April 1st or as January 4th, depending on which parsing culture your system defaults to.
Other type providers in FSharp.Data (such as the CSV type provideryou could ) allow you to configure how each column will be parsed, but that's not an option the HTML type provider gives you. (Which is a bit of a missing feature, of course). But since the HTML type provider does allow you to specify the culture info for datetime and number parsing, one way you might be able to work around this is specify a culture that does not use / as a separator (but still uses . as a decimal point, since otherwise if the HTML you're parsing has numbers written like 1,000 for one thousand, that could be interpreted as 1). One such culture is the en-IN culture ("English (India)"), where the date separator is - and the decimal point is ..
So try passing Culture=System.Globalization.CultureInfo.GetCultureInfo("en-IN") in your HtmlProvider options, and see if that helps it stop treating fractions as dates.
The following combination of functions worked:
// http://www.fssnip.net/29/title/Regular-expression-active-pattern
module Solution =
open System
open System.Text.RegularExpressions
open FSharp.Data
let (|Regex|_|) pattern input =
let m = Regex.Match(input, pattern)
if m.Success then Some(List.tail [ for g in m.Groups -> g.Value ])
else None
let ptrnFraction = #"^([0-9]?[0-9]?)(\/)([0-9]?[0-9]?)$"
let ptrnDateTime = #"(\d{2})\/(\d{2})\/(\d{4}) (\d{2}):(\d{2}):(\d{2})"
let ToFraction input =
match input with
| Regex ptrnFraction [ numerator; operator; denominator ] ->
(numerator + operator + denominator).ToString()
| Regex ptrnDateTime [ day; month; year; hours; minutes; seconds ] ->
(day + "/" + month).ToString()
| _ -> "Not valid!"
let dtInput = #"05/09/2017 00:00:00"
let frcInput = #"13/20"
let outDate = ToFraction dtInput
printfn "Out Date: %s" outDate
let outFraction = ToFraction frcInput
printfn "Out Fraction: %s" outFraction
//Output:> Out Date: 05/09 Out Fraction: 13/20
Thus, I was able to replace:
"\"" + row.``Fraction``.ToString() + "\"" + ";" |> writer.WriteLine
with:
"\"" + ToFraction(row.``Fraction``.ToString()) + "\"" + ";" |> writer.Write
Thanks to #rmunn for the clarity of his explanations and the benefit of his expertise.
I am doing a school project in which I need to make a "sort of" vigenere cipher in which the user inputs both the keyword and plaintext. However the vigenere assumes a=0 whereas I am to assume a=1 and I have changed this accordingly for my program. However I am required to make my cipher work for both lower and upper case, How could I make this also work for lower case, it may be a stupid question but I'm very confused at this point and I'm new to programming, thanks.
REM Variables
plaintext$=""
PRINT "Enter the text you would like to encrypt"
INPUT plaintext$
keyword$=""
PRINT "Enter the keyword you wish to use"
INPUT keyword$
encrypted$= FNencrypt(plaintext$, keyword$)
REM PRINTING OUTPUTS
PRINT "Key = " keyword$
PRINT "Plaintext = " plaintext$
PRINT "Encrypted = " encrypted$
PRINT "Decrypted = " FNdecrypt(encrypted$, keyword$)
END
DEF FNencrypt(plain$, keyword$)
LOCAL i%, offset%, Ascii%, output$
FOR i% = 1 TO LEN(plain$)
Ascii% = ASCMID$(plain$, i%)
IF Ascii% >= 65 IF Ascii% <= 90 THEN
output$ += CHR$((66 + (Ascii% + ASCMID$(keyword$, offset%+1)) MOD 26))
ENDIF
offset% = (offset% + 1) MOD LEN(keyword$)
NEXT
= output$
DEF FNdecrypt(encrypted$, keyword$)
LOCAL i%, offset%, n%, o$
FOR i% = 1 TO LEN(encrypted$)
n% = ASCMID$(encrypted$, i%)
o$ += CHR$(64 + (n% + 26 - ASCMID$(keyword$, offset%+1)) MOD 26)
offset% = (offset% + 1) MOD LEN(keyword$)
NEXT
= output$
You can always convert from upper to lowercase and the Stringlib library contains a function for doing this.
First import stringlib at the top of your program:
import #lib$+"stringlib"
then convert strings using:
plaintext$ = fn_lower(plaintext$)