I am writing some code where I have multiple dictionaries for my data. The reason being, I have multiple core objects and multiple smaller assets and the user must be able to choose a smaller asset and have some function off in the distance run the code with the parent noted.
An example of one of the dictionaries: (I'm working in ROBLOX Lua 5.1 but the syntax for the problem should be identical)
local data = {
character = workspace.Stores.NPCs.Thom,
name = "Thom", npcId = 9,
npcDialog = workspace.Stores.NPCs.Thom.Dialog
}
local items = {
item1 = {
model = workspace.Stores.Items.Item1.Main,
npcName = "Thom",
}
}
This is my function:
local function function1(item)
if not items[item] and data[items[item[npcName]]] then return false end
end
As you can see, I try to index the dictionary using a key from another dictionary. Usually this is no problem.
local thisIsAVariable = item[item1[npcName]]
but the method I use above tries to index the data dictionary for data that is in the items dictionary.
Without a ton of local variables and clutter, is there a way to do this? I had an idea to wrap the conflicting dictionary reference in a tostring() function to separate them - would that work?
Thank you.
As I see it, your issue is that:
data[items[item[npcName]]]
is looking for data[“Thom”] ... but you do not have such a key in the data table. You have a “name” key that has a “Thom” value. You could reverse the name key and value in the data table. “Thom” = name
Related
Having some trouble understanding how to create a Perl hash from a DB select statement.
$sth=$dbh->prepare(qq{select authorid,titleid,title,pubyear from books});
$sth->execute() or die DBI->errstr;
while(#records=$sth->fetchrow_array()) {
%Books = (%Books,AuthorID=> $records[0]);
%Books = (%Books,TitleID=> $records[1]);
%Books = (%Books,Title=> $records[2]);
%Books = (%Books,PubYear=> $records[3]);
print qq{$records[0]\n}
print qq{\t$records[1]\n};
print qq{\t$records[2]\n};
print qq{\t$records[3]\n};
}
$sth->finish();
while(($key,$value) = each(%Books)) {
print qq{$key --> $value\n};
}
The print statements work in the first while loop, but I only get the last result in the second key,value loop.
What am I doing wrong here. I'm sure it's something simple. Many thanks.
OP needs better specify the question and do some reading on DBI module.
DBI module has a call for fetchall_hashref perhaps OP could put it to some use.
In the shown code an assignment of a record to a hash with the same keys overwrites the previous one, row after row, and the last one remains. Instead, they should be accumulated in a suitable data structure.
Since there are a fair number of rows (351 we are told) one option is a top-level array, with hashrefs for each book
my #all_books;
while (my #records = $sth->fetchrow_array()) {
my %book;
#book{qw(AuthorID TitleID Title PubYear)} = #records;
push #all_books, \%book;
}
Now we have an array of books, each indexed by the four parameters.
This uses a hash slice to assign multiple key-value pairs to a hash.
Another option is a top-level hash with keys for the four book-related parameters, each having for a value an arrayref with entries from all records
my %books;
while (my #records = $sth->fetchrow_array()) {
push #{$books{AuthorID}}, $records[0];
push #{$books{TitleID}}, $records[1];
...
}
Now one can go through authors/titles/etc, and readily recover the other parameters for each.
Adding some checks is always a good idea when reading from a database.
I have the following table in Lua:
local a = {orszag = {"Ausztria", "Albánia", "Azerbajdzsán"}, varos = {"Ankara", "Amszterdam", "Antwerpen"}, fiu = {"Arnold", "Andor", "Albert"}, lany = {"Anna", "Anasztázia", "Amanda"}}
I would like to do the following:
for i in a["orszag"] do etc. (for example compare all the words in the value to the user input)
But when I do so I get the following: attempt to call a table value.
So I know, it works in python for example, but is it possible somehow to do this in Lua as well?
Use
for k,v in pairs(a["orszag"]) do
I'm currently trying to connect a Lua Script with a GS WebApp. The connection is working but due to my lack of knowledge in GScripting I'm not sure why it isn't saving my data correctly.
In the Lua side I'm just passing in a hard-code a random name and simple numerical userid.
local HttpService = game:GetService("HttpService")
local scriptID = scriptlink
local WebApp
local function updateSpreadSheet ()
local playerData = (scriptID .. "?userid=123&name:Jhon Smith")
WebApp = HttpService:GetAsync(playerData)
end
do
updateSpreadSheet()
end
On the Google Script side i'm only saving the data on the last row and then add the value of the userid and the name.
function doGet(e) {
console.log(e)
// console.log(f)
callName(e.parameter.userid,e.parameter.name);
}
function callName(userid,name) {
// Get the last Row and add the name provided
var sheet = SpreadsheetApp.getActiveSheet();
sheet.getRange(sheet.getLastRow() + 1,1).setValues([userid],[name]);
}
However, the only data the script is saving is the name, bypassing the the userid for reasons I have yet to discover.
setValues() requires a 2D array and range dimensions should correspond to that array. The script is only getting 1 x 1 range and setValues argument is not a 2D array. Fix the syntax or use appendRow
sheet.getRange(sheet.getLastRow() + 1,1,1,2).setValues([[userid,name]]);
//or
sheet.appendRow([userid,name])
References:
appendRow
I have 2 Dictionaries:
StatePops={'AL':4887871, 'AK':737438, 'AZ':7278717, 'AR':3013825}
StateNames={'AL':'Alabama', 'AK':'Alaska', 'AZ':'Arizona', 'AR':'Arkansas'}
I am trying to merge so the Value of StateNames is the Key for StatePops.
Ex.
{'Alabama': 4887871, 'Alaska': 737438, ...
I also have to display the name of states w/ population over 4million.
Any help is appreciated!!!
You have not specified in what programming language you want this problem to be solved.
Nonetheless, here is a solution in Python.
state_pops = {
'AL': 4887871,
'AK': 737438,
'AZ':7278717,
'AR':3013825
}
state_names = {
'AL':'Alabama',
'AK':'Alaska',
'AZ':'Arizona',
'AR':'Arkansas'
}
states = dict([([state_names[k],state_pops[k]]) for k in state_pops])
final = {k:v for k, v in states.items() if v > 4000000}
print(states)
print(final)
First, you can merge two dictionaries with the predefined dict python function in the states variable as such. Here, k is an iterator and it is used as index for state_names and state_pops.
Then, store the filtered dictionary in final where the states.items() is used to access the keys and values in states and type-cast it as a string with the str function.
There may be more simpler solutions but this is as far as I can optimize the problem.
Hope this helps.
Dictionary Keys cannot be changed in Python. You need to either add the modified key-value pair to the dictionary and then delete the old key, or you can create a new dictionary. I'd opt for the second option, i.e., creating a new dictionary.
myDict = {}
for i in StatePops:
myDict.update({StateNames[i] : StatePops[i]})
This outputs myDict as
{'Alabama': 4887871, 'Alaska': 737438, 'Arizona': 7278717, 'Arkansas': 3013825}
I'm trying to migrate some Hadoop Map Reduce code to Spark and I have doubts about how to manage map and reduce transformations when the schema of either the key or value change from input to output.
I have avro files with Indicator records that I want to process somehow. I already have this code that works:
val myAvroJob = new Job()
myAvroJob.setInputFormatClass(classOf[AvroKeyInputFormat[Indicator]])
myAvroJob.setOutputFormatClass(classOf[AvroKeyOutputFormat[Indicator]])
myAvroJob.setOutputValueClass(classOf[NullWritable])
AvroJob.setInputValueSchema(myAvroJob, Schema.create(Schema.Type.NULL))
AvroJob.setInputKeySchema(myAvroJob, Indicator.SCHEMA$)
AvroJob.setOutputKeySchema(myAvroJob, Indicator.SCHEMA$)
val indicatorsRdd = sc.newAPIHadoopRDD(myAvroJob.getConfiguration,
classOf[AvroKeyInputFormat[Indicator]],
classOf[AvroKey[Indicator]],
classOf[NullWritable])
val myRecordOnlyRdd = indicatorsRdd.map(x => (doSomethingWith(x._1), NullWritable.get)
val indicatorPairRDD = new PairRDDFunctions(myRecordOnlyRdd)
indicatorPairRDD.saveAsNewAPIHadoopDataset(myAvroJob.getConfiguration)
But this code works since the schema of the input and ouput keys does not change, is always Indicator. In hadoop Map Reduce you can define a map or reduce functions and modify the schema from input to output. In fact, I have map functions which process every Indicator record and generates a new record SoporteCartera. How can I do this in spark? It is possible from the same RDD or I have to define 2 different RDDs and pass from one to another somehow?
Thanks for your help.
To answer my own question... the problem was that you cannot change the RDD type, you must define a different RDD, so I solved it with the above code:
val myAvroJob = new Job()
myAvroJob.setInputFormatClass(classOf[AvroKeyInputFormat[SoporteCartera]])
myAvroJob.setOutputFormatClass(classOf[AvroKeyOutputFormat[Indicator]])
myAvroJob.setOutputValueClass(classOf[NullWritable])
AvroJob.setInputValueSchema(myAvroJob, Schema.create(Schema.Type.NULL))
AvroJob.setInputKeySchema(myAvroJob, SoporteCartera.SCHEMA$)
AvroJob.setOutputKeySchema(myAvroJob, Indicator.SCHEMA$)
val soporteCarteraRdd = sc.newAPIHadoopRDD(myAvroJob.getConfiguration,
classOf[AvroKeyInputFormat[SoporteCartera]],
classOf[AvroKey[SoporteCartera]],
classOf[NullWritable])
val indicatorsRdd = soporteCarteraRdd.map(x => (fromSoporteCarteraToIndicator(x._1), NullWritable.get))
val indicatorPairRDD = new PairRDDFunctions(indicatorsRdd)
indicatorPairRDD.saveAsNewAPIHadoopDataset(myAvroJob.getConfiguration)