lookup Questions
8
Solved
Where can I find information on the differences between calling on a column within a data.frame via:
df <- data.frame(x=1:20,y=letters[1:20],z=20:1)
df$x
df["x"]
They both return the "same" ...
3
Solved
I'd like to do the following:
Lookup a Vec for a certain key, and store it for later use.
If it doesn't exist, create an empty Vec for the key, but still keep it in the variable.
How to do this...
17
Solved
I came across the dict method get which, given a key in the dictionary, returns the associated value.
For what purpose is this function useful? If I wanted to find a value associated with a key in ...
Quiberon asked 14/6, 2012 at 21:10
4
Solved
I would like to know if there is a simple way to use the matched pattern in a preg_replace as an index for the replacement value array.
e.g.
preg_replace("/\{[a-z_]*\}/i", "{$data_ar...
Randolphrandom asked 26/4, 2013 at 13:37
5
Solved
In mongo, after doing an aggregation with $lookup, I would like the request to return only some fields and not the whole document.
I have the following query :
db.somecollection.aggregate([{
$lo...
Peccant asked 23/2, 2016 at 16:57
9
Solved
How can I find the index of an item in a list without looping through it?
Currently this doesn't look very nice - searching through the list for the same item twice, just to get the index:
var oPro...
21
Solved
How do I add a new key to an existing dictionary? It doesn't have an .add() method.
Verrucose asked 21/6, 2009 at 22:7
4
Solved
We have a file with about 46 million records in CSV format. Each record has about 18 fields and one of them is a 64 byte ID. We have another file with about 167K unique IDs in it. The records corre...
4
Solved
The Pandas lookup function is to be deprecated in a future version. As suggested by the warning, it is recommended to use .melt and .loc as an alternative.
df = pd.DataFrame({'B': ['X', 'X' , 'Y', ...
2
I try to make fast dictionary lookups in python by iterating a list of integers. I noticed that unordered lookups are approximately 10x slower than ordered ones.
Is there any way to speed up unorde...
Moisture asked 28/2, 2023 at 21:3
6
Solved
The MSDN explains Lookup like this:
A Lookup<TKey, TElement>
resembles a Dictionary<TKey,
TValue>. The difference is that a
Dictionary<TKey, TValue> maps keys to single valu...
7
I'm a former C++/STL programmer trying to code a fast marching algorithm using C#/.NET technology...
I'm searching for an equivalent of STL method map::insert that insert a value at given key if no...
Intangible asked 20/6, 2011 at 9:3
4
Solved
I have two collections
User
{
"_id" : ObjectId("584aac38686860d502929b8b"),
"name" : "John"
}
Role
{
"_id" : ObjectId("584aaca6686860d502929b8d"),
"role" : "Admin",
"userId" : "584aac3868...
Impresa asked 12/12, 2016 at 3:7
9
Solved
I have need of a sort of specialized dictionary. My use case is this: The user wants to specify ranges of values (the range could be a single point as well) and assign a value to a particular range...
Dumah asked 27/1, 2010 at 14:18
5
Solved
I have a 4x4 table. All the values in the table are unique.
A B C D
1 a b c d
2 e f g h
3 i j k l
4 m n o p
How do i find the address of a particular value? I've tried =CELL("address",MATCH(A1...
Palmitate asked 15/8, 2018 at 12:27
2
Solved
How to join only specific fields? When using $lookup, mongo returns the whole document.
Let's say that's my data:
users
[
{ id: 0, name: "Bob", adj: 1 },
{ id: 1, name: "Will", adj: 2 },
]
a...
4
Solved
Is there a way to require multiple keys for the .ToLookup function provided by LINQ?
I will admit that this seems non-intuitive at first, and I'm expecting that there's no actual way to do this, b...
5
>>> d2
{'egg': 3, 'ham': {'grill': 4, 'fry': 6, 'bake': 5}, 'spam': 2}
>>> d2.get('spamx',99)
99
>>> d2.get('ham')['fry']
6
I want to get value of fry inside of ham, if...
Buonarroti asked 9/8, 2010 at 6:14
8
Solved
I am having some trouble replacing values in a dataframe. I would like to replace values based on a separate table. Below is an example of what I am trying to do.
I have a table where every row is...
2
Solved
I have a pandas lookup table which looks like this
Grade Lower_Boundary Upper_Boundary
1 -110 -96
2 -96 -91
3 -91 -85
4 -85 -81
5 -81 -77
6 -77 -72
7 -72 -68
8 -68 -63
9 -63 -58
10 -58 -54
11 -54 ...
1
Solved
Many Ansible modules are designed to accept file paths as a parameter, the but lack the possibility to supply the contents of the file directly. In cases where the input data actually comes from so...
Goatskin asked 7/1, 2022 at 17:22
4
Solved
Given two arrays $A1 and $A2, sort $A1 in such a way that the relative order among the elements will be same as those in $A2. For the elements not present in $A2, move them to the back of the array...
1
Solved
I recently asked about the fastest way to create powers of ten, and it turned out that the fastest way is actually a bit of a sneaky workaround, where you create all the possible values first, and ...
Haakon asked 4/11, 2021 at 11:10
6
Solved
Recently began branching out from my safe place (R) into Python and and am a bit confused by the cell localization/selection in Pandas. I've read the documentation but I'm struggling to understand ...
Ideologist asked 27/2, 2015 at 4:12
5
Solved
I have a variable of type Dictionary<MyType, List<MyOtherType>>
I want to convert it to a Lookup<MyType, MyOtherType>.
I wanted to use Lambda functions to first, flatten the dicti...
Nest asked 23/9, 2009 at 6:7
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