data"aws_network_interface""node1"{
id="eni-0dfe5asdf7ajk5"
}
the output of above data source is a list of Private_ips with the length of 4
as
[10.198.10.1,10.198.10.2,10.198.10.3,10.198.10.4]
Here I am trying to create NLB with the target by IP.
I am also confused on how the index works in element() function -my requirement is to pick the 3rd element as [10.198.0.3] from the above list if my var.lbcount=1 and when my var.lbcount=2 I need to pick the 4th element from the above list as 10.198.10.4.
resource"aws_lb_target_group_attachment""tga"
{
target_group_arn="${aws_lb_target_group.tg.arn}"
target_id="${element(data.aws_network_interface.node1.private_ips,4}"
}
As I stated
index=4
I am getting target_id as a 1st element in the list as [10.198.10.1] which is wrong, how to throw an error or exception if the index is out of range of length of the list.
How can I make sure we should only allow 1,2,3 as the index in element() function and if we pass 4, which is more than the list of values the terraform to throw an error?
In general, Terraform would use list[0] again if length(LIST) = 3 and the current count.index = 4.
You can, however, use a simple conditional for your use-case (pseudocode):
count = "${var.MAX_INDEX > length(LIST) ? length(LIST) : var.MAX_INDEX"
This would set count to the length of the list if your MAX_INDEX is larger than the length of your list. Otherwise it would set count to your MAX_INDEX.
Related
I am quite new to XQuery and I am trying to get a list of all elements and all attributes.
It should look like this:
element1 #attributex, #attribue y, ...
element 2 #attribute x, #attribute y, ...
element 3 #attribute x, #attribute y, ...
I am trying this so far, but the error "Item expected, sequence found":
for $x in collection("XYZ")
let $att := local-name(//#*)
let $ele := local-name(//*)
let $eleatt := string-join($ele, $att)
return $eleatt
I feel like I am turning an easy step into a complicated one. Please help.
Thanks in advance, Eleonore
//#* gives you a sequence of attribute nodes, //* a sequence of element nodes. In general to apply a function like local-name() to each item in a sequence, for nodes you have three options:
Use a final step /local-name() e.g. //#*/local-name() or //*/local-name()
In XQuery 3.1 use the map operator ! e.g. //#*!local-name()
Use a for .. return expression e.g. for $att in //#* return local-name($att)
The local-name() function takes a single node as its argument, not a sequence of nodes. To apply the same function to every node in a sequence, using the "!" operator: //*!local-name().
The string-join() function takes two arguments, a list of strings, and a separator. You're trying to pass two lists of strings. You want
string-join((//*!local-name(), //#*!local-name()), ',')
Of course you might also want to de-duplicate the list using distinct-values(), and to distinguish element from attribute names, or to associate attribute names with the element they appear on. That's all eminently possible. But for that, you'll have to ask a more precise question.
I'm currently working on a problem relating to dictionaries where you write a function that deletes all key/value pairs in which a value is larger than a given number. Here is the code:
def remove_numbers_larger_than(number, dict1):
for i, value in dict1.items():
if value > number :
del dict1[i]
return dict1
else:
return dict1
dict1 = {'animals': 6 , 'truck': 3, 'country': 2}
number = 2
print(remove_numbers_larger_than(number, dict1))
Normally I would expect to see output: {'country': 2} given that it is the only value smaller than the given number but instead I get output: {'truck': 3, 'country': 2}. It seems to be taking the initial condition and removing the first value but then the loop stops.
Only the first item is getting deleted because you immediately return from the function in the first iteration of the for loop. To loop through every value, you shouldn't return until after the for loop is over.
However, there's also another issue with the code. You are iterating through a list (dict1.items()) which will change when you remove items from the dictionary. An easy fix is to make a copy of the items list that you iterate over, allowing the original list to change without problems:
for i, value in list(dict1.items()):
I iterate thru items of a dictionary "var_dict".
Then as I iterate in a for loop, I need to update the dictionary.
I understand that is not possible and that triggers the runtime error I experienced.
My question is, do I need to create a different dictionary to store data? As is now, I am trying to use same dictionary with different keys.
I know the problem is related to iteration thru the key and values of a dictionary and attempt to change it. I want to know if the best option in this case if to create a separate dictionary.
for k, v in var_dict.items():
match = str(match)
match = match.strip("[]")
match = match.strip("''")
result = [index for index, value in enumerate(v) if match in value]
result = str(result)
result = result.strip("[]")
result = result.strip("'")
#====> IF I print(var_dict), at this point I have no error *********
if result == "0":
#It means a match between interface on RP PSE2 model was found; Interface position is on PSE2 architecture
print (f'PSE-2 Line cards:{v} Interfaces on PSE2:{entry} Interface PortID:{port_id}')
port_id = int(port_id)
print(port_id)
if port_id >= 19:
#print(f'interface:{entry} portID={port_id} CPU_POS={port_cpu_pos} REPLICATION=YES')
if_info = [entry,'PSE2=YES',port_id,port_cpu_pos,'REPLICATION=YES']
var_dict['IF_PSE2'].append(if_info)
#===> *** This is the point that if i attempt to print var_dict, I get the Error during olist(): dictionary changed size during iteration
else:
#print(f'interface:{entry},portID={port_id} CPU_POS={port_cpu_pos} REPLICATION=NO')
if_info = [entry,'PSE2=YES',port_id,port_cpu_pos,'REPLICATION=NO']
var_dict['IF_PSE2'].append(if_info)
else:
#it means the interface is on single PSE. No replication is applicable. Just check threshold between incoming and outgoing rate.
if_info = [entry,'PSE2=NO',int(port_id),port_cpu_pos,'REPLICATION=NO']
var_dict['IF_PSE1'].append(if_info)
I did a shallow copy and that allowed me to iterate a dictionary copy and make modifications to the original dictionary. Problem solved. Thanks.
(...)
temp_var_dict = var_dict.copy()
for k, v in temp_var_dict.items():
(...)
Someone please help me understand this. I have the following code below. I am trying to append index[i]-1 to an empty array. However I am getting this error: "BoundsError: attempt to access 0-element Array{Any,1} at index [1]" :
sample_size_array = [9,5,6,9,2,6,9]
n_minus_1 = []
array_length = length(sample_size_array)
for i in 1:array_length
n_minus_1[i].append(sample_size_array[i] -1)
end
println(n_minus_1)
If Julia does not understand array[0] then why is i starting at 0 and not at 1?
Your code has two problems:
in the first iteration you are trying to access n_minus_1 array at index 1 while this array is still empty (has 0 length) - this throws you an error;
in Julia you do not invoke methods using a . (this symbol is used for different purposes - in this case it is parsed as field access and also would throw an error later)
To solve both those problems use push! function which appends an element at the end of an array. The code could look like this:
sample_size_array = [9,5,6,9,2,6,9]
n_minus_1 = []
array_length = length(sample_size_array)
for i in 1:array_length
push!(n_minus_1, sample_size_array[i]-1)
end
println(n_minus_1)
However in this case the whole operation can be written even simpler as:
n_minus_1 = sample_size_array .- 1
and you do not need any loop (and here you see another use of . in Julia - in this case we use it to signal that we want to subtract 1 from every element of sample_size_array).
I'm trying to get the number of records with QML LocalStorage, which uses sqlite. Let's take this snippet in account:
function f() {
var db = LocalStorage.openDatabaseSync(...)
db.transaction (
function(tx) {
var b = tx.executeSql("SELECT * FROM t")
console.log(b.rows.length)
var c = tx.executeSql("SELECT COUNT(*) FROM t")
console.log(JSON.stringify(c))
}
)
}
The output is:
qml: 3
qml: {"rowsAffected":0,"insertId":"","rows":{}}
What am I doing wrong that the SELECT COUNT(*) doesn't output anything?
EDIT: rows only seems empty in the second command. Calling
console.log(JSON.stringify(c.rows.item(0)))
gives
qml: {"COUNT(*)":3}
Two questions now:
Why is rows shown as empty
How can I access the property inside c.rows.item(0)
In order to visit the items, you have to use:
b.rows.item(i)
Where i is the index of the item you want to get (in your first example, i belongs to [0, 1, 2] for you have 3 items, in the second one it is 0 and you can query it as c.rows.item(0)).
The rows field appears empty and it is a valid result, for the items are not part of the rows field itself (indeed you have to use a method to get them, as far as I know that method could also be a memento that completely enclose the response data) and the item method is probably defined as not enumerable (I cannot verify it, I'm on the beach and it's quite difficult to explore the Qt code now :-)). You can safely rely on the length parameter to know if there are returned values, thus you can iterate over them to print them out. I did something like that in a project of mine and it works fine.
The properties inside item(0) have the same names given for the query. I suggest to rewrite that query as:
select count(*) as cnt from t
Then, you can get the count as:
c.rows.item(0).cnt