How to read a CNF file? - cnf

i'm working on argumentation system made by Dung
how to read this file content?
it's a cnf file describe an abstract argumentation framework
enter image description here

The file defines Boolean expressions written in Conjuctive Normal Form. Basically it’s clauses joined by AND, with each variable in the clause ORed together.
The first line of the file format (.cnf) starts with
p cnf num_variables num_clauses
So In your example 7 is the number of variables, 12 is the number of clauses.
Then each line defines a clause. For example:
(A v B v C) ^ (A v D v E) ^ (B v C v D)
number of variables is 5 (ABCDE), number of clauses is 3 (separated by AND)
The variable indexing starts from 1, wirh each clause on a seperate line. Each line ends with a 0 to signify end of the clause. To show a negation, add a “-“ (negative sign) before the variable.
p cnf 5 3
1 2 3 0
1 4 5 0
2 3 4 0
I don’t know what the e is in the first line.

Related

Check the result of a math expression in mysql

Let's say I have a table, which has four columns (a, b, oper and c) and some primary key column. oper means arithmetic operation (+ - * /) here.
a b oper c
-------------
2 3 + 5
4 2 / 3
6 1 * 9
8 5 - 3
As, we can see in some cases, a <oper> b != c. So, my question is how to filter out such cases?
I've heard of execute, which is used for executing statements, but I don't know how to use it inside where clause.
Also, I'm not generalizing the oper to any arithmetic operation, but it would be nice to know, if any function exists.
SELECT *
FROM table
WHERE с != CASE oper WHEN '+' THEN a+b
WHEN '-' THEN a-b
WHEN '*' THEN a*b
WHEN '/' THEN a/b
ELSE NULL END
fiddle

How do I Query for used BETWEEN Operater for text searches in MySql database?

I have a SQL Table in that i use BETWEEN Operater.
The BETWEEN Operater selects values within range. The values can be numbers, text , dates.
stu_id name city pin
1 Raj Ranchi 123456
2 sonu Delhi 652345
3 ANU KOLKATA 879845
4 K.K's Company Delhi 345546
5 J.K's Company Delhi 123456
I have a query like this:-
SELECT * FROM student WHERE stu_id BETWEEN 2 AND 4 //including 2 & 4
SELECT * FROM `student` WHERE name between 'A' and 'K' //including A & not K
Here My Question is why not including K.
but I want K also in searches.
Don't use between -- until you really understand it. That is just general advice. BETWEEN is inclusive, so your second query is equivalent to:
WHERE name >= 'A' AND
name <= 'K'
Because of the equality, 'K' is included in the result set. However, names longer than one character and starting with 'K' are not -- "Ka" for instance.
Instead, be explicit:
WHERE name >= 'A' AND
name < 'L'
Of course, BETWEEN can be useful. However, it is useful for discrete values, such as integers. It is a bit dangerous with numbers with decimals, strings, and date/time values. That is why I encourage you to express the logic as inequalities.
In supplement to gordon's answer, one way to get what you're expecting is to turn your name into a discrete set of values:
SELECT * FROM `student` WHERE LEFT(name, 1) between 'A' and 'K'
You need to appreciate that K.K's Company is alphabetically AFTER the letter K on its own so it is not BETWEEN, in the same way that 4.1 is not BETWEEN 2 and 4
By stripping it down to just a single character from the start of the string it will work like you expect, but take cautionary note, you should always avoid running functions on values in tables, because if you had a million names, thats a million strings that mysql has to strip out to just the first letter and it might no longer be able to use an index on name, battering the performance.
Instead, you could :
SELECT * FROM `student` WHERE name >= 'A' and name < 'L'
which is more likely to permit the use of an index as you aren't manipulating the stored values before comparing them
This works because it asks for everything up to but not including L.. Which includes all of your names starting with K, even kzzzzzzzz. Numerically it is equivalent to saying number >= 2 and number < 5 which gives you all the numbers starting with 2, 3 or 4 (like the 4.1 from before) but not the 5
Remember that BETWEEN is inclusive at both ends. Always revert to a pattern of a >= b and a < c, a >= c and a < d when you want to specify ranges that capture all possible values
Compare in lexicographical order, 'K.K's Company' > 'K'
We should convert the string to integer. You can try that mysql script with CAST and SUBSTRING. I've updated your script here. It will include the last record as well.
SELECT * FROM student WHERE name CAST(SUBSTRING(username FROM 1) AS UNSIGNED)
BETWEEN 'A' AND 'K';
The script will work. Hope it will helps to you.
Here I've attached my test sample.

Can Octave combine elements and indices in expressions?

I'd like to create a matrix of elements with each value in column i the ith power of the value in column 1. Easy with a for loop, but is there a way to combine matrix elements and their indices in expressions?
Do you mean something like this?
M = M(:,1) .^ (1:size(M,2));
It is easy to generate an array of indices to manipulate and/or operate on.
Note: For older versions of MATLAB the above gives an error, you need to use bsxfun:
M = bsxfun(#power, M(:,1), 1:size(M,2));
Note 2: If your inputs are v=[3;5;7] and n=3 you can translate the above to
M = v .^ (1:n);
What about this:
F = #(x, n) bsxfun (#realpow, x(:), 1:n);
Example:
>> F ([3;5;7], 3)
ans =
3 9 27
5 25 125
7 49 343

MYSQL - Find rows, where part of search string matches part of value in column

I wasn't able to find this anywhere, here's my problem:
I have a string like '1 2 3 4 5' and then I have a mysql table that has a column, let's call it numbers, that look like this:
numbers
1 2 6 8 9 14
3
1 5 3 6 9
7 8 9 23 44
10
I am trying to find the easiest way (hopefully in a single query) to find the rows, where any of the numbers in my search string (1 or 2 or 3 or 4 or 5) is contained in the numbers column. In the give example I am looking for rows with 1,2 and 3 (since they share numbers with my search string).
I am trying to do this with a single query and no loops.
Thanks!
The best solution would be to get rid of the column containing a list of values, and use a schema where each value is in its own row. Then you can use WHERE number IN (1, 2, 3, 4, 5) and join this with the table containing the rest of the data.
But if you can't change the schema, you can use a regular expression.
SELECT *
FROM yourTable
WHERE numbers REGEXP '[[:<:]](1|2|3|4|5)[[:<:]]'
[[:<:]] and [[:<:]] match the beginning and end of words.
Note that this type of search will be very slow if the table is large, because it's not feasible to index it.
Here is a start point (split string function) : http://blog.fedecarg.com/2009/02/22/mysql-split-string-function/ := SplitString(string,delimiter,position)
Create a function so it converts a string to an array := stringSplitted(string,delimiter)
Create a function so it compares two arrays :=arrayIntersect(array1, array2)
SELECT numbers
FROM table
WHERE arrayIntersect(#argument, numbers)
Two function definitions with loops and one single query without any loop
SELECT * FROM MyTable WHERE (numbers LIKE '%1%' OR numbers LIKE '%2%')
or you can also use REGEX something like this
SELECT * FROM events WHERE id REGEXP '5587$'

SQLite SELECT statement for column name where column has a value

What SQLite statement do I need to get the column name WHERE there is a value?
COLUMN NAME: ALPHA BRAVO CHARLIE DELTA ECHO
ROW VALUE: 0 1 0 1 1
All I want in my return is: Bravo, Delta, Echo.
Your request is not entirely clear, but you appear to be asking for a SELECT statement that will return not data but rather columns names, and not a predictable number of values but rather a number values that depend on the data in the table.
For instance,
A B C D E
0 1 0 1 1
would return (B,D,E) whereas
A B C D E
1 0 1 0 0
would return (A, C).
If that's what you're asking, this is not something that SQL does. SQL retrieves data from the table and an SQL result set always has the same number of columns per row.
To accomplish your goal, you would have to retrieve all columns that might have a value in the table and then, in your program code, check for the value in each column and accrue a list of column names that had values.
Also, consider what happens when there is more than one row to examine and the distribution of values differ. In other words, what's the expected result if the data looks like this:
A B C D E
- - - - -
0 1 0 1 1
1 0 1 0 0
[Also, note that all the columns in your example have values, some 0, some 1. What you really want is a list of column names where the column contains a value of 1.]
Finally, consider that your inability to easily get the results you need from your data might indicate a flaw in the data model you're using. For instance, if you were to structure your data like this:
TagName TagValue
------- --------
Alpha 0
Bravo 1
Charlie 0
Delta 1
Echo 1
you could then obtain your results with SELECT TagName FROM Tags WHERE TagValue = 1.
Furthermore, if 0 and 1 are really the only two possible values (indicating boolean "presence" or "absence" of the tag) then you could remove the TagValue column and the rows for Alpha and Charlie entirely (you'd INSERT a row into the table to add tag and DELETE a row to remove it).
A design along these lines seems to model your data more accurately and allows you to entire new tags to the system without having to issue an ALTER TABLE command.
http://sqlfiddle.com/#!9/1407e/1
SELECT CONCAT(IF(ALPHA,'ALPHA,',''),
IF(BRAVO,'BRAVO,',''),
IF(CHARLIE,'CHARLIE,',''),
IF(DELTA,'DELTA,',''),
IF(ECHO,'ECHO',''))
FROM table1