I need a Bar Graph in Gruff with two Bars.
For two subjects, I loop through to get the values for activity and grade :
sub = ["English", "Maths"]
activity = []
grade = []
sub.each do |sub|
activity.push(sub["activity"].to_i)
grade.push(sub["grade"].to_i)
end
Now, I am using these values for my Bar Graph.
g = Gruff::Bar.new('500x250')
g.maximum_value = 100
g.minimum_value = 0
g.y_axis_increment = 15
g.data( "Activity", activity.inspect)
g.data( "Summative", grade.inspect)
g.labels = {0 => 'English', 1 => 'Language II'}
g.write('images/overall_score.png')
But, this throws an error " comparison of String with 0 failed". I need the data to be printed as
g.data( "Activity", [10,20])
puts activity.inspect prints the array as above ex: [10,20]
Looks like the values are treated as strings. What should I do to resolve this.
Any help is greatly appreciated.
Cheers!
Actually inspect method returns String. I think you should just pass your arrays to data method like this:
g.data("Activity", activity)
g.data("Summative", grade)
Related
I've tried this
def matrix():
A = [[0,1,2,3,4],[5,6,7,8],[9,10,11,12],[13,14,15,16]]
return(A[1:2][0])
I want the function to return the value 5 and 9
If you would like to get the first element of the 2nd and 3rd rows it is:
def matrix():
A = [[0,1,2,3,4],[5,6,7,8],[9,10,11,12],[13,14,15,16]]
return (A[1][0], A[2][0])
This returns (5,9) as a tuple.
If you would like to parameterize it as such:
def matrix(rows):
# rows is a tuple or array like (1,2) with the indexes
A = [[0,1,2,3,4],[5,6,7,8],[9,10,11,12],[13,14,15,16]]
result = [] # empty list
for i in rows:
result.append(A[i][0])
return result
After calling the method like this: matrix((1,2)), it returns [5,9] as a list.
New to Ruby and have run out of ideas. I have an array of books that I would like to 1) Shelve 2) Find which shelf it is on 3) Remove it from the associated shelf if found. For brevity I have an array of 6 books. Each shelf contains 5 books.
library_catalog = [ "Book1", "Book2", "Book3", "Book4", "Book5", "Book6" ]
shelves = Hash.new(0)
catalog_slice = library_catalog.each_slice(5).to_a
count = 1
catalog_slice.each do | x |
shelves.merge!(count=>x)
count+=1
end
From this I know have a Hash w/ arrays as such
{1=>["Book1", "Book2", "Book3", "Book4", "Book5"], 2=>["Book6"]}
This is where I'm having trouble traversing the hash to find a match inside the array and return the key(shelf). If I have title = "Book1" and I am trying to match and return 1, how would I go about this?
I think this should work.
shelves.select { |k,v| v.include?("Book1")}.keys.first
selected the hashes that have a value equal to the title you are looking for (in this case "Book1")
get the keys for these hashes as an array
get the first entry in the array.
to remove the Book from the shelf try this:
key = shelves.select { |k,v| v.include?("Book1")}.keys.first
shelves[key].reject! { |b| b == "Book1" }
get a reference to the array and then reject the entry you want to remove
I have the following array, that I use to later write the header on an Excel file.
fields = ["fileName", "type", "id"]
And then I have the following code that reads values from an XML:
filename = xml.xpath('//path/filename').text
type = xml.xpath('//path/type').text
id = xml.xpath('//path/id').text
The I iterate the initial array (fields) in order to set the Excel cells to the values extracted in the previous step:
row = 2
c = 1
fields.each do |content|
ws.Cells(row,c).Value = content
c = c + 1
I'm trying to have the array's (fields) contents to variable names instead of strings in order to be able to reuse the head fields.
Can anyone recommend a way of making it possible?
This sounds like you need to use a Hash to associate field names to the values you extracted:
fields = {
"fileName" => xml.xpath('//path/filename').text,
"type" => xml.xpath('//path/type').text,
"id" => xml.xpath('//path/id').text
}
row=2
c=1
fields.each do |key,value|
ws.Cells(row,c).Value = value
c=c+1
end
Using MongoDB and the Ruby driver, I'm trying to calculate the rankings for players in my app, so I'm sorting by (in this case) pushups, and then adding a rank field and value per object.
pushups = coll.find.sort(["pushups", -1] )
pushups.each_with_index do |r, idx|
r[:pushups_rank] = idx + 1
coll.update( {:id => r }, r, :upsert => true)
coll.save(r)
end
This approach does work, but is this the best way to iterate over objects and update each one? Is there a better way to calculate a player's rank?
Another approach would be to do the entire update on the server by executing a javascript function:
update_rank = "function(){
var rank=0;
db.players.find().sort({pushups:-1}).forEach(function(p){
rank +=1;
p.rank = rank;
db.players.save(p);
});
}"
cn.eval( update_rank )
(Code assumes you have a "players" collection in mongo, and a ruby variable cn that holds a conection to your database)
I have a table that is filled with random content that a user enters. I want my users to be able to rapidly search through this table, and one way of facilitating their search is by sorting the table alphabetically. Originally, the table looked something like this:
myTable = {
Zebra = "black and white",
Apple = "I love them!",
Coin = "25cents"
}
I was able to implement a pairsByKeys() function which allowed me to output the tables contents in alphabetical order, but not to store them that way. Because of the way the searching is setup, the table itself needs to be in alphabetical order.
function pairsByKeys (t, f)
local a = {}
for n in pairs(t) do
table.insert(a, n)
end
table.sort(a, f)
local i = 0 -- iterator variable
local iter = function () -- iterator function
i = i + 1
if a[i] == nil then
return nil
else
return a[i], t[a[i]]
end
end
return iter
end
After a time I came to understand (perhaps incorrectly - you tell me) that non-numerically indexed tables cannot be sorted alphabetically. So then I started thinking of ways around that - one way I thought of is sorting the table and then putting each value into a numerically indexed array, something like below:
myTable = {
[1] = { Apple = "I love them!" },
[2] = { Coin = "25cents" },
[3] = { Zebra = "black and white" },
}
In principle, I feel this should work, but for some reason I am having difficulty with it. My table does not appear to be sorting. Here is the function I use, with the above function, to sort the table:
SortFunc = function ()
local newtbl = {}
local t = {}
for title,value in pairsByKeys(myTable) do
newtbl[title] = value
tinsert(t,newtbl[title])
end
myTable = t
end
myTable still does not end up being sorted. Why?
Lua's table can be hybrid. For numerical keys, starting at 1, it uses a vector and for other keys it uses a hash.
For example, {1="foo", 2="bar", 4="hey", my="name"}
1 & 2, will be placed in a vector, 4 & my will be placed in a hashtable. 4 broke the sequence and that's the reason for including it into the hashtable.
For information on how to sort Lua's table take a look here: 19.3 - Sort
Your new table needs consecutive integer keys and needs values themselves to be tables. So you want something on this order:
SortFunc = function (myTable)
local t = {}
for title,value in pairsByKeys(myTable) do
table.insert(t, { title = title, value = value })
end
myTable = t
return myTable
end
This assumes that pairsByKeys does what I think it does...