Is it possible to get a list of declared variables with a VimL (aka VimScript) expression? I'd like to get the same set of values that will be presented for a command using -complete=expression. The goal is to augment that list for use in a user-defined command completion function.
You can use g: as a dictionary that holds all global variables, so:
let globals = keys(g:)
will give you all the names. The same applies to the other scopes: b:, s:, w:, etc. See :help internal-variables for the complete list.
You can get something similar using keys of g:, b:, t:, w: and v: dictionaries, but beware of the following facts:
There is no equivalent to this dictionaries if you want to complete options.
Some variables like count (but not g:count or l:count), b:changedtick and, maybe, others are not present in this dictionaries.
Some vim hacker may add key ### to dictionary g:, but it won't make expression g:### valid variable name (but adding 000 there will). Though g:["###"] will be a valid expression.
Related
I have data frame which a column name starts with number, I want to delete the column with the following code, but there is error:
delete!(features, [:3SsnPorchH])
UndefVarError: SsnPorchH not defined
Your problem is that :3SsnPorchH is not correctly parsed as a symbol, but as follows:
julia> :(:3SsnPorchH)
:($(QuoteNode(3)) * SsnPorchH)
When a symbol cannot be correctly parsed, it most often works to put the "name" into parentheses:
julia> :(3SsnPorchH)
:(3SsnPorchH)
Another thing you could do is using the Symbol constructor directly:
julia> Symbol("3SsnPorchH")
Symbol("3SsnPorchH")
(But I'm not sure if that's a good idea -- maybe you lose interning then.)
That being said, it's probably a good idea to give columns a name which is a valid Julia identifier. This gives you construction using DataFrame with keyword arguments, and allows for certain macros to identify variables with columns. You'll just have an easier time.
I have a list of hosts inbound in the form of one string separated by commas.
EXAMPLE: "host01,host02,host03,"
I have this line that was an array of strings but I need it to be a map[string]interface{}
Here is what it is how do I make it a map[string]interface{}?
• Removing the trailing or any trailing comma.
hosts := []string{strings.TrimSuffix(hostlist, ",")}
• Later I split them on the comma like this.
hosts = strings.split(hosts[0], ",")
I just need to make it so names are keys and the values are unknown from APIs so an interface{}.
Thanks and forgive me I know this is super simple I am just not seeing it.
Loop over your slice of strings. Set each map entry to nil.
There is no fancy syntax like Python's list comprehensions or Perl's freaky group assignments.
And remember that StackOverflow's tag info is often really useful. See: https://stackoverflow.com/tags/go/info
And from there to the language specification. One bit that will help is https://golang.org/ref/spec#For_range if you aren't familiar with Go's for syntax to loop over slices.
I'm getting the XDMP-NOTANODE error when I try to run an XQuery in MarkLogic. When I loaded my xml documents I loaded meta data files with them. I'm a student and I don't have experience in XQuery.
error:
[1.0-ml] XDMP-NOTANODE: (err:XPTY0019) $article/article/front/article-meta/title-group/article-title -- xs:untypedAtomic("
") is not a node
Stack Trace
At line 3 column 77:
In xdmp:eval("(for $article in fn:distinct-values(/article/text()) ...", (), <options xmlns="xdmp:eval"><database>4206169969988859108</database> <root>C:\mls-projects\pu...</options>)
$article := xs:untypedAtomic("
")
1. (for $article in fn:distinct-values(/article/text())
2.
3. return (fn:distinct-values($article/article/front/article-meta/title-group/article-title)
4.
5.
Code:
(
for $article in fn:distinct-values(/article/text())
return (
fn:distinct-values($article/article/front/article-meta/title-group/article-title/text())
)
)
Every $article is bound to an atomic value (fn:distinct-values() returns a sequence of atomic values). Then you try to apply a path expression (using the / operator) on $article. Which is forbidden, as the path operator requires its LHS operator to be nodes.
I am afraid your code does not make sense enough for me to suggest you an actual solution. I can only pinpoint where the error is.
Furthermore, using text() at the end of a path is most of the time a bad idea. And if /article is a complex document, it is certainly not what you want. One of the text nodes you select (most likely the first one) is simply one single newline character.
What do you want to achieve?
Your $article variable is bound to an atomic value, not a node() from the article document. You can only use an XPath axis on a node.
When you apply the function distinct-values() in the for statement, it returns simple string values, not the article document or nodes from it.
You can probably make things work by using the values in a predicate filter like this:
for $article-text in fn:distinct-values(/article/text())
return
fn:distinct-values(/article[text()=$article-text]/front/article-meta/title-group/article-title/text())
Note: The above XQuery should avoid the XDMP-NOTANODE error, but there are likely easier (and more efficient) solutions for achieving your goal. If you were to post a sample of your document and describe what you are trying to achieve, we could suggest alternatives.
Bit of a wild guess, but you have two distinct-values in your code. That makes me think you want a unique list of articles, and then finally a unique list of article-title's. I would hope you already have unique articles in your database, unless you are explicitly attempting to de-duplicate them.
In case you just want the overall unique list of article titles, I would do something like:
distinct-values(
for $article in collection()/article
return
$article/front/article-meta/title-group/article-title
)
HTH!
I am trying to use the hash package in R to replicate dictionary behavior in python. I have created it like this,
library(hash)
titles = hash(NAME = list("exact"=list('NAME','Age'), "partial"=list()),
Dt = list("exact"=list('Dt'), "partial"=list()),
CC = list("exact"=list(), "partial"=list()))
I can access the keys in the hash using keys(titles) , values using values(titles), and access values for a particular key using values(titles['Name']).
But how can I access the elements of the inner list? e.g. list('NAME','Age') ?
I need to access the elements based on its names, in this case - "exact" or else I need to know which element of the outer list this element belong to, whether its "exact" or "partial".
Simply:
titles[["NAME"]][["exact"]]
as hrbmstr wrote. There's nothing special about this whatsoever.
In your nested-list, "exact" and "partial" are simply two string keys. Again, there's no special magic significance to their names.
Also, this is in fact the recommended proper R syntax (esp. when the key is variable), it's not "bringing gosh-awful Python syntax".
I'm having trouble working with a data table in R. This is probably something really simple but I can't find the solution anywhere.
Here is what I have:
Let's say t is the data table
colNames <- names(t)
for (col in colNames) {
print (t$col)
}
When I do this, it prints NULL. However, if I do it manually, it works fine -- say a column name is "sample". If I type t$"sample" into the R prompt, it works fine. What am I doing wrong here?
You need t[[col]]; t$col does an odd form of evaluation.
edit: incorporating #joran's explanation:
t$col tries to find an element literally named 'col' in list t, not what you happen to have stored as a value in a variable named col.
$ is convenient for interactive use, because it is shorter and one can skip quotation marks (i.e. t$foo vs. t[["foo"]]. It also does partial matching, which is very convenient but can under unusual circumstances be dangerous or confusing: i.e. if a list contains an element foolicious, then t$foo will retrieve it. For this reason it is not generally recommended for programming.
[[ can take either a literal string ("foo") or a string stored in a variable (col), and does not do partial matching. It is generally recommended for programming (although there's no harm in using it interactively).