Graphite: merge series containing multiple values - grafana

Is there a way to merge two "dictionaries" of values in Graphite? That is to say, I want to start with a series:
AnimalsByCountry
England
Cats
Dogs
France
Cats
Dogs
Birds
And combine them into series:
AnimalsInWorld
Cats // = AnimalsByCountry.England.Cats + AnimalsByCountry.France.Cats
Dogs // = AnimalsByCountry.England.Dogs + AnimalsByCountry.France.Dogs
Birds // = AnimalsByCountry.France.Birds
Sorry if this is an obvious question; I'm new to Graphite and this seems like a simple operation but I can't find any functions to do it in the documentation.

Use https://graphite.readthedocs.io/en/latest/functions.html#graphite.render.functions.groupByNodes
groupByNodes(animalsbycountry.*.*,'sum',2)

Related

Query from OpenStreetMap

At the moment I'm using the Overpass API to query from OpenStreetMap using https://overpass-turbo.eu/ but when I use the following code, not all the schools in the area appear on the map (e.g. Holy Cross College doesn't appear).
area[name = "Council of the City of Ryde"];
node(area)[amenity = school];
out;
Anyone know why this might be the case?
Thanks for any help!
OpenStreetMap data consists of three basic elements: nodes, ways and relations. Your query searches only for nodes. Some schools will be mapped as ways and a few others as relations.
You have to change your query in order to search for all three elements:
area[name = "Council of the City of Ryde"];
(
node(area)[amenity = school];
way(area)[amenity = school];
relation(area)[amenity = school];
);
out;
Alternatively just use the keyword nwr to search for all three elements:
area[name = "Council of the City of Ryde"];
nwr(area)[amenity = school];
out;
If there are still missing schools then either they are mapped with a different tag or they are missing in OSM. In the second case feel free to add them yourself.

How to reduce code in Swift when dealing with variables and if statements?

I am currently building an app to teach myself Swift so am still very new. I’ve encountered a problem. The app is a timetable creator. I have up to twelve subjects that all have points. These points are then spread across days. I have a concept for code that will allocate the points fine using loops but wondered whether there was something to reduce the amount of code rather than, what I currently have, something like this for each subject:
subject1.monpts = 20
subject1.tuepts = 20
subject1.wedpts = 20
subject1.thurpts = 20
subject1.fripts = 20
subject1.satpts = 20
subject1.sunpts = 20
This, x12, is a lot of code. But I need it so that each subject has an option for points for each day of the week (which the app will then allocate time based on these points). To print the timetable, I am putting each subjectX.daypts together but this means I’m writing out 12 subjects for each day.
I also need to only display something if the variable actually has a value. I plan to do this using if statements but that means writing a statement for every single variable which at the moment is 12 x 7 = 48! E.g. (ignore the formating - just for concept)
if subjects1.monpts = 0 {
subjects1monLabel = isHidden.false
// or just a print / don't print statement
}
I feel as if I'm missing an easier way to do this!
Here is a picture that explains the concept a bit better:
If you want to save information about those fields you can have a dictionary with keys of a enum and values of ints like so:
enum WeekDay: CaseIterable {
case monday, tuesday, wednesday, thursday, friday, saturday, sunday
}
struct Subject {
var pointsForWeekDay: [WeekDay: Int]
}
Now you could do:
var pointsForWeekDay = Dictionary(uniqueKeysWithValues:
WeekDay.allCases.map { weekDay in
return (weekDay, 20)
}
)
var subject = Subject(pointsForWeekDay: pointsForWeekDay)
CaseIterable allows you to access all values of your enum.
Map takes every weekDay and creates an array of tuples with your Int values.
And finally you can combine that to have a complete Dictionary with uniqueKeysWithValues initializer, which takes an array of the produced tuples.
Your whole vision of how to organize this material is upside down. Start by thinking about what all your subjects have in common: points for each of the seven days, label hidden for each of the seven days, and so forth. Now incorporate that into a type (a struct): Subject. Now instead of subjects1..., subjects2... and so forth, you have an Array of Subject.
So: any time you have variables named with a number, that should be an array instead. Any time you have clumps of repeated concepts, that should be a type instead.
Even the notion of the seven days of the week could itself be condensed in the same way. If all we're talking about is points per day, an array of seven numbers would do.
So we'd end up with a skeleton like this:
struct Subject {
var dayPoints : [Int]
}
var myTwelveSubjects : [Subject]
...and you can build that out as more requirements come online, such as whether a day is hidden.

What are "zip" methods in Scala and Spark?

In Scala, Spark and a lot of other "big data"-type frameworks, languages, libraries I see methods named "zip*". For instance, in Scala, List types have an inherent zipWithIndex method that you can use like so:
val listOfNames : List[String] = getSomehow()
for((name,i) <- listOfNames.zipWithIndex) {
println(s"Names #${i+1}: ${name}")
}
Similarly Spark has RDD methods like zip, zipPartitions, etc.
But the method name "zip" is totally throwing me off. Is this a concept in computing or discrete math?! What's the motivation for all these methods with "zip" in their names?
They are named zip because you are zipping two datasets like a zipper.
To visualize it, take two datasets:
x = [1,2,3,4,5,6]
y = [a,b,c,d,e,f]
and then zip them together to get
1 a
2 b
3 c
4 d
5 e
6 f
I put the extra spacing just give the zipper illusion as you move down the dataset :)

Is there a way to have two values from one variable/constant in Swift?

I currently have to make a school project where I have to write into a textfield a food and the values of the price and calories must appear to the user. Is there a way to have a variable or better yet, a constant have more than one value? Thanks
You can use Tuples to save several values for one variable. A tuple can hold values with different types.
Here an example:
let lasagne = (1200, 5.50)
print("The lasagne has \(lasagne.0) kCal and costs \(lasagne.1)$")
you can also name the inner elements and then access them by their name:
let pizza = (calories: 900, price: 4)
print("The pizza has \(pizza.calories) kCal and costs \(pizza.price)$")

How to groupBy groupBy?

I need to map through a List[(A,B,C)] to produce an html report. Specifically, a
List[(Schedule,GameResult,Team)]
Schedule contains a gameDate property that I need to group by on to get a
Map[JodaTime, List(Schedule,GameResult,Team)]
which I use to display gameDate table row headers. Easy enough:
val data = repo.games.findAllByDate(fooDate).groupBy(_._1.gameDate)
Now the tricky bit (for me) is, how to further refine the grouping in order to enable mapping through the game results as pairs? To clarify, each GameResult consists of a team's "version" of the game (i.e. score, location, etc.), sharing a common Schedule gameID with the opponent team.
Basically, I need to display a game result outcome on one row as:
3 London Dragons vs. Paris Frogs 2
Grouping on gameDate let's me do something like:
data.map{case(date,games) =>
// game date row headers
<tr><td>{date.toString("MMMM dd, yyyy")}</td></tr>
// print out game result data rows
games.map{case(schedule,result, team)=>
...
// BUT (result,team) slice is ungrouped, need grouped by Schedule gameID
}
}
In the old version of the existing application (PHP) I used to
for($x = 0; $x < $this->gameCnt; $x = $x + 2) {...}
but I'd prefer to refer to variable names and not the come-back-later-wtf-is-that-inducing:
games._._2(rowCnt).total games._._3(rowCnt).name games._._1(rowCnt).location games._._2(rowCnt+1).total games._._3(rowCnt+1).name
maybe zip or double up for(t1 <- data; t2 <- data) yield(?) or something else entirely will do the trick. Regardless, there's a concise solution, just not coming to me right now...
Maybe I'm misunderstanding your requirements, but it seems to me that all you need is an additional groupBy:
repo.games.findAllByDate(fooDate).groupBy(_._1.gameDate).mapValues(_.groupBy(_._1.gameID))
The result will be of type:
Map[JodaTime, Map[GameId, List[(Schedule,GameResult,Team)]]]
(where GameId is the type of the return type of Schedule.gameId)
Update: if you want the results as pairs, then pattern matching is your friend, as shown by Arjan. This would give us:
val byDate = repo.games.findAllByDate(fooDate).groupBy(_._1.gameDate)
val data = byDate.mapValues(_.groupBy(_._1.gameID).mapValues{ case List((sa, ra, ta), (sb, rb, tb)) => (sa, (ta, ra), (tb, rb)))
This time the result is of type:
Map[JodaTime, Iterable[ (Schedule,(Team,GameResult),(Team,GameResult))]]
Note that this will throw a MatchError if there are not exactly 2 entries with the same gameId. In real code you will definitely want to check for this case.
Ok a soultion from Régis Jean-Gilles:
val data = repo.games.findAllByDate(fooDate).groupBy(_._1.gameDate).mapValues(_.groupBy(_._1.gameID))
You said it was not correct, maybe you just didnt use it the right way?
Every List in the result is a pair of games with the same GameId.
You could pruduce html like that:
data.map{case(date,games) =>
// game date row headers
<tr><td>{date.toString("MMMM dd, yyyy")}</td></tr>
// print out game result data rows
games.map{case (gameId, List((schedule, result, team), (schedule, result, team))) =>
...
}
}
And since you dont need a gameId, you can return just the paired games:
val data = repo.games.findAllByDate(fooDate).groupBy(_._1.gameDate).mapValues(_.groupBy(_._1.gameID).values)
Tipe of result is now:
Map[JodaTime, Iterable[List[(Schedule,GameResult,Team)]]]
Every list again a pair of two games with the same GameId