Is there a toInt, or parseInt function? There appears to be a StringToBinary, but I don't need a binary representation, I just want the number.
Be aware, that Number() works in one case unexpected. Strings will converted to 0, but "0" also. You have no chance, to see the difference. It's written in the help file (A string beginning with letters has a numeric value of zero.), but it is not satisfactory.
I've made my own function, that exactly works, like Number(). But if you pass an expression, that is a string or starts with a string, this returns an numeric value of your choice (default: 0xDEADBEEF) and sets #error to 1.
; #FUNCTION# ====================================================================================================================
; Name ..........: _Number
; Description ...: Works like "Number()", but avoids to convert a string to number 0!
; Syntax ........: _Number($_Expression, $_Flag)
; Parameters ....: $_Expression - An expression to convert into a number.
; ...............: $_iErrReturn - The numeric return value in error case. Default: 0xDEADBEEF
; ...............: You get also the default value by passing "Default" or empty string instaed.
; ...............: $_Flag - Can be one of the following:
; ...............: $NUMBER_AUTO (0) = (default) the result is auto-sized integer.
; ...............: $NUMBER_32BIT (1) = the result is 32bit integer.
; ...............: $NUMBER_64BIT (2) = the result is 64bit integer.
; ...............: $NUMBER_DOUBLE (3) = the result is double.
; Return values .: Success The converted number, if $_Expression is a number or starts with a (un/signed) number.
; ...............: Failure The Value from "$_iErrReturn", sets #error = 1 $_Expression is a string or starts with a string.
; Author ........: BugFix
; Remarks .......: In contrast to Number(), you get only a number, if $_Expression is a number or starts with it.
; ...............: Because 0 is also a number, Number() give unclear results:
; ...............: Number("foo") returns 0. Number("0") returns also 0. "0" converts to the real number 0, but "foo" also??
; ===============================================================================================================================
Func _Number($_Expression, $_iErrReturn=0xDEADBEEF, $_Flag=0)
If $_iErrReturn = Default Or $_iErrReturn = '' Then $_iErrReturn = 0xDEADBEEF
If StringRegExp($_Expression, '^(-\s\d|-\d|\d)') Then
Return Number($_Expression, $_Flag)
Else
Return SetError(1, 0, $_iErrReturn)
EndIf
EndFunc ;==>_Number
I figured it out, use the Number() function.
Number("5") becomes 5.
Related
I am getting confused tracing the following recursive approach to find the longest common substring. The last two lines are where my confusion is. Specifically how is the count variable getting the answer when characters of both string matches? In the last line which "count" does this refer to i.e count in the function definition or the updated count from function call? Are there any resources for better understanding of recursions?
int recursive_substr(string a, string b, int m, int n,int count){
if (m == -1 || n == -1) return count;
if (a[m] == b[n]) {
count = recursive_substr(a,b,m-1,n-1,++count);
}
return max(count,max(recursive_substr(a,b,m,n-1,0),recursive_substr(a,b,m-1,n,0)));
}
The first thing to understand is what values to use for the parameters the very first time you call the function.
Consider the two following strings:
std::string a = "helloabc";
std::string b = "hello!abc";
To figure out the length of the longest common substring, you can call the function this way:
int length = recursive_substr(a, b, a.length()-1, b.length()-1, 0);
So, m begins as the index of the last character in a, and n begins as the index of the last character in b. count begins as 0.
During execution, m represents the index of the current character in a, n represents the index of the current character in b, and count represents the length of the current common substring.
Now imagine we're in the middle of the execution, with m=4 and n=5 and count=3.
We're there:
a= "helloabc"
^m
b="hello!abc" count=3
^n
We just saw the common substring "abc", which has length 3, and that is why count=3. Now, we notice that a[m] == 'o' != '!' == b[n]. So, we know that we can't extend the common substring "abc" into a longer common substring. We make a note that we have found a common substring of length 3, and we start looking for another common substring between "hello" and "hello!". Since 'o' and '!' are different, we know that we should exclude at least one of the two. But we don't know which one. So, we make two recursive calls:
count1 = recursive_substr(a,b,m,n-1,0); // length of longest common substring between "hello" and "hello"
count2 = recursive_substr(a,b,m-1,n,0); // length of longest common substring between "hell" and "hello!"
Then, we return the maximum of the three lengths we've collected:
the length count==3 of the previous common substring "abc" we had found;
the length count1==5 of the longest common substring between "hello" and "hello";
the length count2==4 of the longest common substring between "hell" and "hello!".
I'm trying to populate an integer variable from a character variable. If there is any error found I want to show the error message and trace all the possible cases for failure got.
//Defining variable
Define variable char_value as character no-undo initial "kk".
Define variable int_value as integer no-undo.
define variable ix as integer no-undo.
Assign int_value = integer(char_value) no-error.
IF ERROR-STATUS:ERROR OR ERROR-STATUS:NUM-MESSAGES > 0 THEN
DO:
MESSAGE ERROR-STATUS:NUM-MESSAGES
" errors occurred during conversion." SKIP
"Do you want to view them?"
VIEW-AS ALERT-BOX QUESTION BUTTONS YES-NO
UPDATE view-errs AS LOGICAL.
IF view-errs THEN
DO ix = 1 TO ERROR-STATUS:NUM-MESSAGES:
MESSAGE ERROR-
STATUS:GET-NUMBER(ix)
ERROR-STATUS:GET-
MESSAGE(ix).
END.
END.
There are two conditions which I want to know.
What char value I gave so that no. Of error returns will be more than 1.
How can I trace all the possible cases for failure got.
The built-in conversion routine does not do what you want it to do. So you will need to parse your input prior to attempting to convert it. Something like this:
function isDigit returns logical ( input d as character ):
if length( d ) = 1 then
return ( index( "0123456789", d ) > 0 ).
else
return no.
end.
procedure checkInteger:
define input parameter integerString as character no-undo.
define output parameter errorList as character no-undo.
define output parameter ok as logical no-undo.
define variable i as integer no-undo.
define variable n as integer no-undo.
define variable c as character no-undo.
ok = yes.
n = length( integerString ).
do i = 1 to n:
c = substring( integerString, i, 1 ).
if i = 1 and c = "-" then next.
if isDigit( c ) = no then
do:
ok = no.
errorList = errorList + substitute( "The character '&1' at offset &2 is not a valid integer value~n", c, i ).
end.
end.
errorList = trim( errorList, "~n" ). // remove the trailing newline (if any)
return.
end.
define variable ok as logical no-undo.
define variable errorList as character no-undo.
run checkInteger( "12x34y56z789", output errorList, output ok ).
if ok = yes then
message "string is a properly formed integer, go ahead and convert it".
else
message
"string was not correctly formed, do not try to convert it" skip
errorList
view-as alert-box information
.
Note #1 If the input contains unprintable characters the errorList string will display it literally and it will look kind of funny. You could, of course, encode them to be more readable. Doing so is left as an exercise. Or another question.
Note #2 This code makes no attempt to check that the string value will fit into an integer or an int64. That is also left as an exercise.
While you can make your parsing as complex as you like, I would just keep it simple and ensure the user is provided enough information, which in this case is the complete input value:
def var cc as char initial "kk".
def var ii as int.
ii = integer( cc ).
catch e as progress.lang.error:
message quoter( cc, "'" ) e:getMessage(1) view-as alert-box.
end catch.
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 ยง2.1). 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))
i=0
def recursiveIntegers(n):
if n==1:
return 1;
else:
reqval= n-1;
print("less than or equal to the original -->",reqval);
return recursiveIntegers(reqval)
userValue = int(input("Enter value "))
recursiveIntegers(userValue)
What am i missing for this to print out equal values..?
Print 'n' first ... then do that 'reqval = n-1'
I'm stuck in an infinite loop in this function:
let rec showGoatDoorSupport(userChoice, otherGuess, aGame) =
if( (userChoice != otherGuess) && (List.nth aGame otherGuess == "goat") ) then otherGuess
else showGoatDoorSupport(userChoice, (Random.int 3), aGame);;
And here's how I'm calling the function:
showGoatDoorSupport(1, 2, ["goat"; "goat"; "car"]);
In the first condition in the function, I compare the first 2 input parameters (1 and 2) if the are different, and if the item in the list at index "otherGuess" is not equal to "goat", I want to return that otherGuess.
Otherwise, I want to run the function again with a random number between 0-2 as the second input parameter.
The point is to keep trying to run the function until the second parameter doesnt equal the first, and that slot in the List isn't "goat", then return that slot number.
Don't use ==, it checks for physical equality. Use =. Two different strings will never be physically equal, even if they contain the same sequence of characters. (This is necessary, because strings are mutable in OCaml.)
$ ocaml
OCaml version 4.00.0
# "abc" == "abc";;
- : bool = false
# "abc" = "abc";;
- : bool = true
Another to do that is to use the String.compare. An example:
if String.compare str1 str2 = 0 then (* case equal *)
else (* case not equal *)