**351 associations questions.**

Say I have a list of Association,SeedRandom[45]
test = Association[Table[i -> RandomInteger[30], {i, 6}]] <|1 -> 18, ...

I want to draw a DensityPlot similar to below:-DensityPlot[Sin[x] Sin[y], {x, -4, 4}, {y, -3, 3}]But my problem is, I am not given the function itself. I am ...

I have an association dataset with a depth of two (each value is an association too, and the size of the dataset ~ 30000 keys and an average size of values are ~2000 keys association). The dataset ...

I have a list of rules: list = {a1 -> 0, a2 -> 3x, a4 -> 0, a5 -> 5x+3...}.
I would like to append to another list the nonzero rules, which are: ...

Wolfram pages "Mathematica Quick Revision History" in Mathematica 10.0.1 release says:
"New operators and compositions of operators enabled for associations
functions such as Dataset and Query"
...

I have a dataset where values are associations too.
...

Solution: Pi is allowed in training sets, but not in batches generated by the batch generating function
preamble:
I want to generate my own batches of training data for training a deep CNN.
ref/...

I cannot understand why I need a second pure function when trying to sort Association by Key. Here is an example
...

Suppose a matrix is given where both rows and columns are keyed, for example this correlation matrix:
...

I have a extremely simple question on Button. I tried to append values to associations. The Append works good with given value outside button, but once it is inside Button, it doesn't append the value ...

Using Association to generate complicated data types is very comfortable, in particular if one uses those tricks from How to make use of Associations?. However, I ...

There’s an inconsistency in how Missing values are imputed in Query, with ...

I try to calculate the average length (in words) of paragraphs in a document. The data look like:
...

Consider following association:
...

I have an Association[] which is the result of an intensive computation. Its values include the variable x and I would like to ...

I have some issues with the Lookup in Association. My association looks as:
...

I try dynamically to add new keys and update the values of existing keys in given dataset (Association). I implement this by the following code:
...

Bug introduced in 10.4.0 and persisting through 11.3.0
CASE:3824590
[...] Developers are discussing this behavior. [...] I will let you know when I have definite information on this. [...]
...

Given a list of values such asvals = {{{{0., 633.25}, {642.96, 677.34}}, {{591.56, 632.45}, {634.9, 715.6}}}}and a list of "Dimensions" such as
...

I'm very excited about the brand new Dataset function. I have played with it in Wolfram Cloud, and haven't figured out how can I add a new column into an existing <...

Bug present in 10.0.2 or earlier, and fixed in 10.4
If I try to export this toy code as ExpressionML or just XML:
...

It seems ListPlot will somehow drop the trailing list of Associations when the Association ...

I have a set of algebraic expressions of a certain form, and I would like to make them into Associations in a specified way. My expressions are formed of two heads, ...

Let's say I have a table in Mathematica like so:
Where the first row is the header, and first column is also a header (similar to a multiplication table). ie S_AS_A = Es; S_BS_A = ss_sigma;
The ...

Say I have the following code:Merge[{<|"a" -> 1, "b" -> 2|>, <|"a" -> 2, "c" -> 3|>}, Identity]The output is:
...

Considering a DatabaseExample included with Mathematica:
...

I was wondering, why is extracting from an Association slightly faster than extracting from a List?
...

Hello, i make another try... I have to import a file like this below (it is an excel file, i show you just the beginnig. it should have thousend of rows and columns). After i've imported the file i ...

I have some large nested expression containing associations and I'd like to extract the nth key inside one of them, using part syntax.
Here's a tiny example:
...

I'm trying to create a function that builds a replacement rule from a given pattern and I have trouble understanding what's going wrong.
After having written most of the question, I see that it got ...

I have list of associations like this:
...

Bug introduced in 10.4 and fixed in 11.3.0
I create two associations, that are supposed to be exactly the same. And then I want to count the elements at the second level. And I get different results:
...

Given a list of associations tab where each association has keys {"name", "a", "b"}:
...

I would like to have a surjective dictionary that saves the following associations
...

Related to this q: Extract all Values from nested Association
How to extract the direct graph of all Keys in nested Associations...

I have an Association <|0->q^2, 1->2p q, 2->p^2|>, where q=1-p.
I would like to plot the key (0, 1 or 2) ...

I am looking to expand this post, How can a key be renamed in an Association?.
I would like a function that automatically replaces any and all keys with the rule.
Here is what I have so far
...

Parts of Associations can be set with the following syntax:as = <|"a" -> 10|> <|"a" -> 10|>as["b"] = 20;
as...

Missing value vanishes when adding or subtracting DateObject but only when slot-lookup is used, in an Association query:
Given
...

While developing a parallel version of some code, I noticed that looking up an item in an association seemed much slower than in the serial version of the code.
To show the effect, I created the ...

Say I have a Dataset like this:dat=Dataset[<|"a" -> 2, "b" -> "y", "c" -> {2, 3}|>]I want to get the keys of upper levels as elements in the ...

asso = <|"x" -> {
<|"a" -> 5, "b" -> "y", "c" -> {5, 6, 7}|>,
<|"a" -> 6, "b" -> "z", "c" -> {}|>}
|>I want to ...

Lists of Rules or Associations are both a useful way of mapping between values. It also ...

I'm using a construct (more complex in fact as the value_ should take a list) to select some entries from an association with criteria:
...

- dataset
- list-manipulation
- bugs
- query
- pattern-matching
- filtering
- data-structures
- performance-tuning
- replacement
- evaluation
- map
- function-construction
- rule
- functions
- gathering
- assignment
- hold
- language-design
- plotting
- programming
- import
- parallelization
- core-language
- missing
- matrix

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