As the HELP document says:
The FIND function and the INDEX function both search for substrings of characters in a character string. However, the INDEX function does not have the modifier nor the start-position arguments.
so why we have the both functions? Can't we just replace index() with find()?
Thanks in advance.
Welcome to SAS. This is an old language and there are many not so obvious solutions. Despair not, for more often there is an answer than not!
As for your question: They allow a bit different things, but function in similar fashion when doing a simple thing.
Index returns the position of the specified string. Documentation
Find allows you to narrow down the range where you look for. Documentation
As indicated by #Richard, the find() function was added to SAS after the index() function. This can be seen in the "What's New" details SAS provide here.
If, as indicated elsewhere, you have trouble getting to the link, then perform a web search for "What's new in SAS 9", the first result (for me) was from SAS, then within that result look for details on "SAS Language Features". This shows that find() was newly introduced then, with some new abilities compared to index().
Related
We're using the ifnull function in one of our Splunk queries (yes, ifnull not isnull), and I wanted to look up the logic just to be sure, but I can't find it documented anywhere.
It is referenced in a few spots:
SPL data types and clauses
Eval
Where
But I can't find a definition/explanation anywhere on what it actually does. Google seems to be of no help either (constantly wants to redirect me to isnull).
In particular it's also not listed in "common evaluation functions".
Can anyone point me to some documentation about ifnull?
TL;DR; it's an alias for coalesce
Wow, it really is hidden! I managed to find it on my local instance here: ./etc/system/default/searchbnf.conf
example4 = coalesce(null(), "Returned value", null())
comment4 = Takes any number of arguments and returns the first value that is not null. The ifnull function does the exact same thing, so both names are acceptable.
the idea is to take a word and sub out all specified letters for another letter.
Any help on how to make this kind of function work?
The last array_push is not being called because you're returning before. Change it to:
array_push($stepsinchain, $subed);
return $subed;
Since $subed is never stored in the $stepsinchain array, due to the return being before, you're not able to access previous alternations.
array_push is also slower and not recommended when entering one element in an array. Instead, use
$stepsinchain[] = $subed;
It is also much faster as documented at http://www.php.net/manual/en/function.array-push.php#Hcom83388
I have created a simple LabView program shown below that attempts to flatten an array [1,0,3] and then unflatten it and print out the contents.
However, I am unsuccessful in doing so. What am I doing wrong?
What am I doing wrong?
You're not going through tutorials or you're not reading the context help for the unflatten function (Ctrl+H) or you're not reading the full help for the function (right click>>Help) or you're not looking at the examples (from the help or Help>>Find Examples). Take your pick (preferably all four).
If you want an actual answer it is that LV is strictly typed, and therefore you need to tell the unflatten function which data type you want it to output (1D DBL array) and you're not doing that, but the real answer is what's in the previous paragraph - you should use those tools to learn how to find such an answer yourself.
The string returned by Flatten to String only contains the data, not the description of what data type was passed in, so in order to unflatten it again you need to tell Unflatten from String what type it was. You do this by wiring some data of the appropriate type (any data - if it's an array it can be an empty one) to the Type terminal.
I don't think this is immediately obvious from the LabVIEW 2012 help but I think it's fairly clear if you follow the link from the Unflatten from String help page to one of the examples. The Read Flattened Data.vi example has an array wired to the Type input.
Following conversion
SELECT to_tsvector('english', 'Google.com');
returns this:
'google.com':1
Why does TSearch2 engine didn't return something like this?
'google':2, 'com':1
Or how can i make the engine to return the exploded string as i wrote above?
I just need "Google.com" to be foundable by "google".
Unfortunately, there is no quick and easy solution.
Denis is correct in that the parser is recognizing it as a hostname, which is why it doesn't break it up.
There are 3 other things you can do, off the top of my head.
You can disable the host parsing in the database. See postgres documentation for details. E.g. something like ALTER TEXT SEARCH CONFIGURATION your_parser_config
DROP MAPPING FOR url, url_path
You can write your own custom dictionary.
You can pre-parse your data before it's inserted into the database in some manner (maybe splitting all domains before going into the database).
I had a similar issue to you last year and opted for solution (2), above.
My solution was to write a custom dictionary that splits words up on non-word characters. A custom dictionary is a lot easier & quicker to write than a new parser. You still have to write C tho :)
The dictionary I wrote would return something like 'www.facebook.com':4, 'com':3, 'facebook':2, 'www':1' for the 'www.facebook.com' domain (we had a unique-ish scenario, hence the 4 results instead of 3).
The trouble with a custom dictionary is that you will no longer get stemming (ie: www.books.com will come out as www, books and com). I believe there is some work (which may have been completed) to allow chaining of dictionaries which would solve this problem.
First off in case you're not aware, tsearch2 is deprecated in favor of the built-in functionality:
http://www.postgresql.org/docs/9/static/textsearch.html
As for your actual question, google.com gets recognized as a host by the parser:
http://www.postgresql.org/docs/9.0/static/textsearch-parsers.html
If you don't want this to occur, you'll need to pre-process your text accordingly (or use a custom parser).
In this question, a user commented to never use the With block in VB. Why?
"Never" is a strong word.
I think it fine as long as you don't abuse it (like nesting)
IMHO - this is better:
With MyCommand.Parameters
.Count = 1
.Item(0).ParameterName = "#baz"
.Item(0).Value = fuz
End With
Than:
MyCommand.Parameters.Count = 1
MyCommand.Parameters.Item(0).ParameterName = "#baz"
MyCommand.Parameters.Item(0).Value = fuz
There is nothing wrong about the With keyword. It's true that it may reduce readibility when nested but the solution is simply don't use nested With.
There may be namespace problems in Delphi, which doesn't enforce a leading dot but that issue simply doesn't exist in VB.NET so the people that are posting rants about Delphi are losing their time in this question.
I think the real reason many people don't like the With keyword is that is not included in C* languages and many programmers automatically think that every feature not included in his/her favourite language is bad.
It's just not helpful compared to other options.
If you really miss it you can create a one or two character alias for your object instead. The alias only takes one line to setup, rather than two for the With block (With + End With lines).
The alias also gives you a quick mouse-over reference for the type of the variable. It provides a hook for the IDE to help you jump back to the top of the block if you want (though if the block is that large you have other problems). It can be passed as an argument to functions. And you can use it to reference an index property.
So we have an alternative that gives more function with less code.
Also see this question:
Why is the with() construct not included in C#, when it is really cool in VB.NET?
The with keyword is only sideswiped in a passing reference here in an hilarious article by the wonderful Verity Stob, but it's worth it for the vitriol: See the paragraph that starts
While we are on identifier confusion. The with keyword...
Worth reading the entire article!
The With keyword also provides another benefit - the object(s) in the With statement only need to be "qualified" once, which can improve performance. Check out the information on MSDN here:
http://msdn.microsoft.com/en-us/library/wc500chb(VS.80).aspx
So by all means, use it.