I have the following Array of hashes in a rails application:
a = ["{\"ROW1\"=>{\"correct\"=>{\"h\"=>\"10\", \"m\"=>\"11\", \"l\"=>
\"12\"}, \"wrong\"=>{\"h\"=>\"2\", \"m\"=>\"2\", \"l\"=>\"4\"}, \"blank
\"=>{\"h\"=>\"2\", \"m\"=>\"4\", \"l\"=>\"3\"}}, \"ROW2\"=>{\"correct
\"=>{\"h\"=>\"2\", \"m\"=>\"4\", \"l\"=>\"4\"}, \"wrong\"=>{\"h
\"=>\"4\", \"m\"=>\"6\", \"l\"=>\"6\"}, \"blank\"=>{\"h\"=>\"7\",
\"m\"=>\"5\", \"l\"=>\"6\"}}, \"ROW3\"=>{\"correct\"=>{\"h\"=>\"4\",
\"m\"=>\"6\", \"l\"=>\"7\"}, \"wrong\"=>{\"h\"=>\"6\", \"m\"=>\"7\",
\"l\"=>\"5\"}, \"blank\"=>{\"h\"=>\"7\", \"m\"=>\"9\", \"l\"=>
\"3\"}}}"]
I want to access its elements and create a database table from it, in the following format
ROW1 correct h=10, m=11,l=12
wrong h=2, m=2,l=4
blank h=2, m=4,l=3
...and similar for ROW2 and ROW3.
How can I do that?
I tried to access a value using
a["ROW1"]["Correct"]["h"]
...but it returns a nil value.
How to access the values of this array of hashes?
you need to first convert the string to hash which can be done as follows:
require 'json'
a = ["{\"ROW1\"=>{\"correct\"=>{\"h\"=>\"10\", \"m\"=>\"11\", \"l\"=>
\"12\"}, \"wrong\"=>{\"h\"=>\"2\", \"m\"=>\"2\", \"l\"=>\"4\"}, \"blank
\"=>{\"h\"=>\"2\", \"m\"=>\"4\", \"l\"=>\"3\"}}, \"ROW2\"=>{\"correct
\"=>{\"h\"=>\"2\", \"m\"=>\"4\", \"l\"=>\"4\"}, \"wrong\"=>{\"h
\"=>\"4\", \"m\"=>\"6\", \"l\"=>\"6\"}, \"blank\"=>{\"h\"=>\"7\",
\"m\"=>\"5\", \"l\"=>\"6\"}}, \"ROW3\"=>{\"correct\"=>{\"h\"=>\"4\",
\"m\"=>\"6\", \"l\"=>\"7\"}, \"wrong\"=>{\"h\"=>\"6\", \"m\"=>\"7\",
\"l\"=>\"5\"}, \"blank\"=>{\"h\"=>\"7\", \"m\"=>\"9\", \"l\"=>
\"3\"}}}"
]
hash_string = a[0]
hash = JSON.parse hash_string.gsub("\n", '').gsub('=>', ':')
# you access the hash now:
hash["ROW1"]["correct"]["h"]
# => 10
Btw, please note that there is a typo. Instead of Correct, the key is correct with small c instead of capital C.
Hope it helps : )
Related
The following is a stored value for datatype defined as text
text_field = "[{\"shop_id\"=>110, \"budget\"=>\"040\"}, {\"shop_id\"=>111, \"budget\"=>173}, {\"shop_id\"=>141, \"budget\"=>344}, {\"shop_id\"=>142, \"budget\"=>\"020\"}, {\"shop_id\"=>144, \"budget\"=>\"220\"}]"
Thus defined, it is for all intents and operational purposes a ruby String class. The contents represent an array of hashes.
How can this string become the array of hashes so that one can call
text_field_array.each do |hash|
shop = Shop.find(hash[shop_id])
shop_budget = shop.budget + hash[budget]
[...]
end
Use eval
> eval(text_field)
=> [{"shop_id"=>110, "budget"=>"040"},
{"shop_id"=>111, "budget"=>173},
{"shop_id"=>141, "budget"=>344},
{"shop_id"=>142, "budget"=>"020"},
{"shop_id"=>144, "budget"=>"220"}]
NOTE: Be careful about it. Make sure the text doesn't have malicious code in the string. Read more about it here https://ruby-hacking-guide.github.io/security.html
I've got a model that I need to group by the :sending_ip, which is a "cidr" column in the database.
#count_hash = Webhook.group('sending_ip').count
Resulting in this hash:
{#<IPAddr: IPv4:213.32.165.239/255.255.255.255>=>127000, #<IPAddr: IPv4:153.92.251.118/255.255.255.255>=>228000}
I cannot figure out how to reference this type of key. Below are some examples of the ways that I've tried to call these keys. All of them return nil or error.
#count_hash[#<IPAddr: IPv4:213.32.165.239/255.255.255.255>]
#count_hash["#<IPAddr: IPv4:213.32.165.239/255.255.255.255>"]
#count_hash[<IPAddr: IPv4:213.32.165.239/255.255.255.255>]
#count_hash["#<IPAddr: IPv4:213.32.165.239/255.255.255.255>"]
Elsewhere in my app, I've got a simpler example that works great. The other example groups by esp, which results in this hash:
{"hotmail"=>1000, "gmail"=>354000}
The second hash, I can refer to easily
#count_hash["gmail"]
To obtain the expected result of 354000
How can I achieve this same functionality with the previous hash that was grouped by sending_ip? Thank you in advance for your insight.
This:
#<IPAddr: IPv4:213.32.165.239/255.255.255.255>
is the result of calling #inspect on an instance of IPAddr. So the keys are IPAddr instances and you can say:
ip = IPAddr.new('213.32.165.239')
#count_hash[ip]
# 127000
Or you could iterate over the hash:
#count_hash.each { |ip, n| ... }
or over its keys:
#count_hash.keys.each { |ip| ... }
depending on what you need to do. You could even convert the keys to strings if that's more convenient:
#count_hash = #count_hash.transform_keys(&:to_s)
# or
#count_hash.transform_keys!(&:to_s)
I am sending a list of checkbox selected from PHP file to our Rails API server. All checked items' ID's will be sent in json format (campaign_ids in json_encode from PHP):
I got a URL being passed to our API like this
Started PUT "/campaigns/function.json?campaign_ids=["6","7"]&user_id=0090000007"
I need to get the campaign_ids ["6","7"] and process it like any other array using array.each do || end
How can I convert this to an array so I can use array.each?
The following sample code can achieve it but I think there could be a better way?
campaign_ids = params[:campaign_ids].to_s # [\"6\",\"7\"]
campaign_ids = campaign_ids.gsub(/[^0-9,]/,'') # 6,7
if campaign_ids.size.to_i > 0 # 3 ??
campaign_ids.split(",").each do |campaign_id|
...
end
end
The correct format of the URL should've been campaign_ids[]=6&campaign_ids[]=7. That would automatically yield an array of [6, 7] when you do params[:campaign_ids].
But assuming you can't change the format of the incorrect parameters, you can still get it via JSON.parse(params[:campaign_ids])
Try this
campaign_ids = JSON.parse(params[:campaign_ids])
You get params[:campaign_ids] as a string.
So, you will have to parse that json string to get array elements.
params[:campaign_ids] is already in your desired array format, you need not convert that to string using to_s.
You can do something like this
campaign_ids = params[:campaign_ids]
campaign_ids.each do |campaign_id|
# do the computation here
end
I have the following hash. Using ruby, I want to get the value of "runs". I can't figure out how to do it. If I do my_hash['entries'], I can dig down that far. If I take that value and dig down lower, I get this error:
no implicit conversion of String into Integer:
{"id"=>2582, "entries"=>[{"id"=>"7", "runs"=>[{"id"=>2588, ...
Assuming that you want to lookup values by id, Array#detect comes to the rescue:
h = {"id"=>2582, "entries"=>[{"id"=>"7", "runs"=>[{"id"=>2588}]}]}
# ⇓⇓⇓⇓⇓⇓⇓ lookup element with id = 7
h['entries'].detect { |e| e['id'] == 7 }['runs']
.detect { |e| e['id'] == 2588 }
#⇒ { "id" => 2588 }
As you have an array inside the entries so you can access it using an index like this:
my_hash["entries"][0]["runs"]
You need to follow the same for accessing values inside the runs as it is also an array.
Hope this helps.
I'm not sure about your hash, as it's incomplete. So , guessing you have multiple run values like:
hash = {"id"=>2582, "entries"=>[{"id"=>"7", "runs"=>[{"id"=>2588}]},
{"id"=>"8", "runs"=>[{"id"=>2589}]},
{"id"=>"9", "runs"=>[{"id"=>2590}]}]}
Then, you can do
hash["entries"].map{|entry| entry["runs"]}
OUTPUT
[[{"id"=>2588}], [{"id"=>2589}], [{"id"=>2590}]]
I have an array of hashes like this:
"[{:id=>15, :name=>"Hockey", :num_of_boxes=>2, :total_price=>6.98}, {:id=>14, :name=>"Baseball", :num_of_boxes=>3, :total_price=>8.97}, {:id=>5, :name=>"Basketball", :num_of_boxes=>2, :total_price=>5.98}]"
In my controller I want to delete the hash where the ID is set as a variable elsewhere. How would I go about doing this?
This is what I was trying to get to work, and I think it's the right path? id would be set in the controller before this method runs:
new_array = eval(#garden.seed_cart).reject { |h| id.include? h['15'] }
Thanks for your help!
Try this:
arr.delete_if { |hash| id.include?(hash[:id]) }
Note (comparison to the #reject suggestion): #delete_if returns the unchanged array if there is nothing to delete. #reject returns nil. Also, #delete_if modifies the array in place, whereas #reject (without !) simply returns a changed version of the array but leaves the original unchanged.
edit
Note: the use of include? here assumes that there may be multiple integers that are being filtered out, i.e. if id (or ids) is actually an array. If you just need to filter one ID, you can use a straightforward comparison with hash[:id] == id inside the block. Thanks to smathy for pointing this out in the comments.
If you have this data:
data = [{:id=>15, :name=>"Hockey", :num_of_boxes=>2, :total_price=>6.98}, {:id=>14, :name=>"Baseball", :num_of_boxes=>3, :total_price=>8.97}, {:id=>5, :name=>"Basketball", :num_of_boxes=>2, :total_price=>5.98}]
And you want to remove this ids from data:
ids = [14,15]
You can do
new_array = data.reject { |h| ids.include? h[:id] }
And you get
new_array = [{:id=>5, :name=>"Basketball", :num_of_boxes=>2, :total_price=>5.98}]
Note: data in an array (not a string) and ids is an array too.