Legal Statute Sorting Algorithm (Algorithmic Challenge) - node.js

I have designed a down and dirty sorting algorithm for New Jersey Legal Statutes, but I'm looking for a better way. Statutes are formatted in the following manner:
Title - A number < 999 and may include up to 2 letters after the title. Ex. 26, 26A, 26AA
Chapter - Formatted exactly the same as title.
Paragraph - A number < 999 which may be followed by 1-2 letters, and or a decimal point, and or a number < 999, and or a letter, and or another number. Ex. 25, 25.26, 25a, 25a.26, 25a.26b, 25aa.26, etc.
I convert the title and paragraph to decimals by stripping out the whole number in the beginning and dividing by 1000, giving me a decimal value which is converted to a string. I have assigned all letters(converted to lowercase) string values from 01-26. I add those values to the end of the initial whole number string sequentially. Any numbers also mixed in are added as their string value.
The obvious bottleneck is the mess of possibilities in the paragraph section. I have actually split that up to paragraph (pre any decimal) and section. I apply the above logic to the broken down sections if they exist.
As for the sorting 17 < 17A < 17AA < 17B < 18.
An example value conversion of 17B:26bb-2a5.1a5 would break down as the following:
Title- .01702
Chapter- .0260202
Paragraph- .002015
Section- .001015
Some more examples of statutes:
17:2-3
18B:2a-1
19AA:3-56g
26:56a-16
1:56-12.123
2:34–15.12a
The method I've devised is pretty dirty. I had to split it up in sections to ensure I had the correct values for each 'section' converting the whole number part to a decimal. I'm also using JS(Node) which doesn't handle large numbers well.
If anyone has a more efficient/clean way, any thoughts, or feedback, I'd greatly appreciate it.

Related

SyntaxError: Unexpected number in JSON at position 182 [duplicate]

I'm importing some JSON files into my Parse.com project, and I keep getting the error "invalid key:value pair".
It states that there is an unexpected "8".
Here's an example of my JSON:
}
"Manufacturer":"Manufacturer",
"Model":"THIS IS A STRING",
"Description":"",
"ItemNumber":"Number12345",
"UPC":083456789012,
"Cost":"$0.00",
"DealerPrice":" $0.00 ",
"MSRP":" $0.00 ",
}
If I update the JSON by either removing the 0 from "UPC":083456789012, or converting it to "UPC":"083456789012", it becomes valid.
Can JSON really not accept an integer that begins with 0, or is there a way around the problem?
A leading 0 indicates an octal number in JavaScript. An octal number cannot contain an 8; therefore, that number is invalid.
Moreover, JSON doesn't (officially) support octal numbers, so formally the JSON is invalid, even if the number would not contain an 8. Some parsers do support it though, which may lead to some confusion. Other parsers will recognize it as an invalid sequence and will throw an error, although the exact explanation they give may differ.
Solution: If you have a number, don't ever store it with leading zeroes. If you have a value that needs to have a leading zero, don't treat it as a number, but as a string. Store it with quotes around it.
In this case, you've got a UPC which needs to be 12 digits long and may contain leading zeroes. I think the best way to store it is as a string.
It is debatable, though. If you treat it as a barcode, seeing the leading 0 as an integral part of it, then string makes sense. Other types of barcodes can even contain alphabetic characters.
On the other hand. A UPC is a number, and the fact that it's left-padded with zeroes to 12 digits could be seen as a display property. Actually, if you left-pad it to 13 digits by adding an extra 0, you've got an EAN code, because EAN is a superset of UPC.
If you have a monetary amount, you might display it as € 7.30, while you store it as 7.3, so it could also make sense to store a product code as a number.
But that decision is up to you. I can only advice you to use a string, which is my personal preference for these codes, and if you choose a number, then you'll have to remove the 0 to make it work.
One of the more confusing parts of JavaScript is that if a number starts with a 0 that isn't immediately followed by a ., it represents an octal, not a decimal.
JSON borrows from JavaScript syntax but avoids confusing features, so simply bans numbers with leading zeros (unless then are followed by a .) outright.
Even if this wasn't the case, there would be no reason to expect the 0 to still be in the number when it was parsed since 02 and 2 are just difference representations of the same number (if you force decimal).
If the leading zero is important to your data, then you probably have a string and not a number.
"UPC":"083456789012"
A product code is an identifier, not something you do maths with. It should be a string.
Formally, it is because JSON uses DecimalIntegerLiteral in its JSONNumber production:
JSONNumber ::
-_opt DecimalIntegerLiteral JSONFraction_opt ExponentPart_opt
And DecimalIntegerLiteral may only start with 0 if it is 0:
DecimalIntegerLiteral ::
0
NonZeroDigit DecimalDigits_opt
The rationale behind is is probably:
In the JSON Grammar - to reuse constructs from the main ECMAScript grammar.
In the main ECMAScript grammar - to make it easier to distinguish DecimalIntegerLiteral from HexIntegerLiteral and OctalIntegerLiteral. OctalIntegerLiteral in the first place.
See this productions:
HexIntegerLiteral ::
0x HexDigit
0X HexDigit
HexIntegerLiteral HexDigit
...
OctalIntegerLiteral ::
0 OctalDigit
OctalIntegerLiteral OctalDigit
The UPC should be in string format. For the future you may also get other type of UPC such as GS128 or string based product identification codes. Set your DB column to be string.
If an integer start with 0 in JavaScript it is considered to be the Octal (base 8) value of the integer instead of the decimal (base 10) value. For example:
var a = 065; //Octal Value
var b = 53; //Decimal Value
a == b; //true
I think the easiest way to send your number by JSON is send your number as string.

Basic string slicing from indices

I will state the obvious that I am a beginner. I should also mention that I have been coding in Zybooks, which affects things. My textbook hasn't helped me much
I tried sub_lyric= rhyme_lyric[ : ]
Zybooks should be able to input an index number can get only that part of the sentence but my book doesnt explain how to do that. If it throws a [4:7] then it would output cow. Hopefully I have exolained everything well.
You need to set there:
sub_lyric = rhyme_lyric[start_index:end_index]
The string is as a sequence of characters and you can use string slicing to extract any sub-text from the main one. As you have observed:
sub_lyric = rhyme_lyric[:]
will copy the entire content of rhyme_lyric to sub_lyric.
To select only a portion of the text, specify the start_index (strings start with index 0) to end_index (not included).
sub_lyric = rhyme_lyric[4:7]
will extract characters in rhyme_lyric from position 4 (included) to position 7 (not included) so the result will be cow.
You can check more on string slicing here: Python 3 introduction

Keeping only letters and digits in a string

I am recoding some open survey responses in SPSS and am wanting just to keep the usual characters a-z and 1-9
I have done rtrim and ltrim which has worked on the majority, but some strings have trailing spaces remaining, which I am assuming are not actually spaces but are hidden characters.
I have also removed punctuation such as "?" but I imagine there must be a more straightforward way than going through each one.
e.g. I need
"exam'ple! " or " exam!!--ple?"
to say "example"
The following syntax will create a new clean field and copy to it only the digits and letters (uppercase or lowercase) from the original field.
Note that I used 15 as the new field width and as the number of iterations in the loop - please change 15 to the actual width of the original field
do repeat val=1 to 15.
compute #i = number(char.substr(OrigField, val, 1), PIB).
if range(#i, 48, 57) or
range(#i, 65, 90) or
range(#i, 97, 122)
CleanField=concat(rtrim(CleanField), char.substr(OrigField, val, 1)).
end repeat.
exe.
See the link suggested by #user45392 to understand how/why this works.
Also see this list for additional values you can add to the loop if you'd like.

Hyphen with strings in PROC FORMAT

I am working with IC9 codes and am creating somewhat of a mapping between codes and an integer:
proc format library = &formatlib;
invalue category other = 0
'410'-'410.99', '425.4'-'425.99' = 1
I have searched and searched, but haven't been able to find an explanation of how that range actually works when it comes to formatting.
Take the first range, for example. I assume SAS interprets '410'-'410.99' as "take every value between the inclusive range [410, 410.99] and convert it to a 1. Please correct me if I'm wrong in that assumption. Does SAS treat these seeming strings as floating-point decimals, then? I think that must be the case if these are to be numerical ranges for formatting all codes within the range.
I'm coming to SAS from the worlds of R and Python, and thus the way quote characters are used in SAS sometimes is unclear (like when using %let foo = bar... not quotes are used).
When SAS compares string values with normal comparison operators, what it does is compare the byte representation of each character in the string, one at a time, until it reaches a difference.
So what you're going to see here is when a string is input, it will be compared to the 'start' string and, if greater than start, then compared to the 'end' string, and if less than end, evaluated to a 1; if it's not for each pair listed, then evaluated to a zero.
Importantly, this means that some nonsensical results could occur - see the last row of the following test, for example.
proc format;
invalue category other = 0
'410'-'410.99', '425.4'-'425.99' = 1
;
quit;
data test;
input #1 testval $6.;
category=input(testval,category.);
datalines;
425.23
425.45
425.40
410#
410.00
410.AA
410.7A
;;;;
run;
410.7A is compared to 410 and found greater, as '4'='4', '1'='1', '0'='0', '.' > ' ', so greater . Then 410.7A is compared to 410.99 and found less, as '4'='4', '1'='1', '0'='0', '7' < '9', so less. The A is irrelevant to the comparison. But on the row above it you see it's not in the sequence, since A is ASCII 41x and that is not less than '9' (ASCII 39x).
Note that all SAS strings are filled to their full length by spaces. This can be important in string comparisons, because space is the lowest-valued printable character (if you consider space printable). Thus any character you're likely to compare to space will be higher - so for example the fourth row (410#) is a 1 because # is between and . in the ASCII table! But change that to / and it fails. Similarly, change it to byte(13) (through code) and it fails - because it is then less than space (so 410^M, with ^M representing byte(13), is less than start (410)). In informats and formats, SAS will treat the format/informat start/end as being whatever the length that it needs to - so if you're reading a 6 long string, it will treat it as length 6 and fill the rest with spaces.

String matching without using builtin functions

I want to search for a query (a string) in a subject (another string).
The query may appear in whole or in parts, but will not be rearranged. For instance, if the query is 'da', and the subject is 'dura', it is still a match.
I am not allowed to use string functions like strfind or find.
The constraints make this actually quite straightforward with a single loop. Imagine you have two indices initially pointing at the first character of both strings, now compare them - if they don't match, increment the subject index and try again. If they do, increment both. If you've reached the end of the query at that point, you've found it. The actual implementation should be simple enough, and I don't want to do all the work for you ;)
If this is homework, I suggest you look at the explanation which precedes the code and then try for yourself, before looking at the actual code.
The code below looks for all occurrences of chars of the query string within the subject string (variables m; and related ii, jj). It then tests all possible orders of those occurrences (variable test). An order is "acceptable" if it contains all desired chars (cond1) in increasing positions (cond2). The result (variable result) is affirmative if there is at least one acceptable order.
subject = 'this is a test string';
query = 'ten';
m = bsxfun(#eq, subject.', query);
%'// m: test if each char of query equals each char of subject
[ii jj] = find(m);
jj = jj.'; %'// ii: which char of query is found within subject...
ii = ii.'; %'// jj: ... and at which position
test = nchoosek(1:numel(jj),numel(query)).'; %'// test all possible orders
cond1 = all(jj(test) == repmat((1:numel(query)).',1,size(test,2)));
%'// cond1: for each order, are all chars of query found in subject?
cond2 = all(diff(ii(test))>0);
%// cond2: for each order, are the found chars in increasing positions?
result = any(cond1 & cond2); %// final result: 1 or 0
The code could be improved by using a better approach as regards to test, i.e. not testing all possible orders given by nchoosek.
Matlab allows you to view the source of built-in functions, so you could always try reading the code to see how the Matlab developers did it (although it will probably be very complex). (thanks Luis for the correction)
Finding a string in another string is a basic computer science problem. You can read up on it in any number of resources, such as Wikipedia.
Your requirement of non-rearranging partial matches recalls the bioinformatics problem of mapping splice variants to a genomic sequence.
You may solve your problem by using a sequence alignment algorithm such as Smith-Waterman, modified to work with all English characters and not just DNA bases.
Is this question actually from bioinformatics? If so, you should tag it as such.

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