Questions tagged [dataset]

Questions on the Dataset data type and related functionality introduced in version 10. Do not use for questions on data in more generic list format or data-manipulation questions generally.

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5
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2answers
717 views

How do I plot multiple time series from a Dataset?

I have a Dataset ds with a straightforward tabular structure containing one column Date ...
5
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1answer
144 views

DateObject with DateFormat displays incorrectly in Dataset

Bug in 10.4.1 still in 11.0 DateObjects with DateFormat option appear to have the first date part truncated when displayed in a ...
5
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2answers
427 views

How can you replace a column of a Dataset with another column or list?

Consider the dataset below with a "x" and a "CH 1" column: How can I replace the "x" column with a new set of data? For example, how could I replace "x" with values starting from 0 and incrementing ...
5
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1answer
446 views

Selecting rows in a Dataset

I'm struggling to get certain rows from a Dataset. Here's the set: plateData = ResourceData["Large Global Plate Boundaries"] I'd like to do something like this, ...
5
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2answers
875 views

Plot 2 columns from a Dataset on the same plot as lists

I have imported as a csv file and converted to a Dataset. I would now like to plot columns of data (by the column title) as ListPlot. I can do this one column at a time, but cannot combine multiple ...
5
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2answers
153 views

Dataset breaks multi-character StringSplit

Given ds = Dataset[{"a b", "c-d"} ] multi-character StringSplit is broken with Dataset (...
5
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1answer
133 views

PDF for MixtureDistribution fails in Dataset Query in 11.1

I have the results of a process involving FindDistribution as a Dataset of probability distributions. Attempting to plot the <...
5
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2answers
124 views

Filtering a subset of a nested dataset

I have a nested dataset (a result of a JSON import done by Mathematica, curated for this example): ...
5
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1answer
142 views

How to analyze all the data in a directory

I am trying to import, analyze, and save all the .txt files in a specific directory. I can do this with a single .txt file using the following code: ...
5
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2answers
89 views

Replacing “Unmatched” with value from other row - under condition

I have ...
5
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1answer
186 views

Sum some columns in list of associations grouped by other columns

I often need to sum values in a list of Associations according to some columns in that Association. I have a way of doing it, ...
5
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2answers
338 views

Remove rows from dataset using query

MyDataSet[Select[#point[Fsr] == 1 &]] returns the row I want to delete, now I am trying what looks to me the most logic command to remove these rows, which is <...
5
votes
1answer
290 views

ANOVA test on dataset

I have a dataset with 3 groups and two variables. I want to do ANOVA test on the three groups for each variable. Does anyone know how to do this? ...
5
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1answer
656 views

Multicolumn sorting with ordering functions and precedence

I am aware that the question of "how do I sort on a column" has been asked in various forms, most notably this one. While some powerful solutions have been presented, as far as I can find no one ...
5
votes
1answer
762 views

How can I modify specific key values within a dataset?

Given a dataset, is there a way to modify a value? Example ...
5
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1answer
149 views

Dataset: best practices for unordered hierarchical data

Note: the editor warns that this is a "subjective" post, but I am looking for an objective answer (e.g. in relation to easy of use of the many built-in functions, speed, etc). Suppose you have a ...
5
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1answer
153 views

How to judge if two Dataset are equal

I don's sure this is a bug or not.Suppose I have a dataset ...
5
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0answers
39 views

Why this shadowing when dealing with a dataset? [duplicate]

I have a dataset which I use as "dsall" and a function keylist (just for my convenience, nothing spectacular): ...
5
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0answers
242 views

Convert .csv Dataset and store in Databin [closed]

Trying out the new Databin product in the Wolfram Cloud. I have a simple ,-delimited .csv file with a header row which I have imported using the follwing: ...
5
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0answers
250 views

Why is Transpose Dataset slow in one direction

Transpose is faster when it distributes Keys at the 2nd level of a Dataset than when it factors them out. ...
4
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4answers
176 views

Padding a column of lists

I have data in the the form of a table, whose one column is the following ...
4
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3answers
450 views

Select dataset columns after GroupBy

Very basic question. Probably showing my ignorance, but if I have a dataset like the example in the docs ...
4
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2answers
285 views

convert from a dataset to list

I have a Dataset of only 1 column to start with, and I want to StringJoin every element there. Got the error message ...
4
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2answers
240 views

Entropy of the elements of a general data set

I have the following data set, and wish to track the evolution of the entropy of each element within the set. I have evaluated the entropy for some elements, but how does one evaluate the entropy of ...
4
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3answers
2k views

Delete rows from a dataset

I have a dataset built from a call to SemanticImport("/data.csv", Delimiters -> ",") with data.csv of the form: ...
4
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2answers
104 views

How to pull out the underlying query syntax being used by dataset?

Consider the following dataset. titanic = ExampleData[{"Dataset", "Titanic"}] If I use the lookup syntax of the dataset like following it creates an equivalent <...
4
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3answers
199 views

Chart a PairedHistogram from two columns of a Dataset

I'm currently experimenting using the Titanic example data set: titanic = ExampleData[{"Dataset", "Titanic"}] I'm able to extract a specific column and then ...
4
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2answers
519 views

With “named row” nested Datasets: How to Select or Filter rows by row key with criteria from another Dataset?

After some calculations and grouping I have a Dataset similar to the following form: ...
4
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2answers
199 views

Use Select to filter a dataset's sublists

In the following Dataset, I want to use Select to display only rows, which contain numbers in column ...
4
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2answers
173 views

Create composite key - operating across rows in a dataset

I would like to be able to create a new dataset by extracting 2 columns to make a composite key, and also extracting other columns. For example, suppose my dataset looked like: I would like to ...
4
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1answer
143 views

Combine datasets with partially different columns row-wise

I have a problem, which I assume to be trivial, but can't solve it: I have two datasets, ...
4
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2answers
290 views

Merge two database with a common key

I have two list: in one of them the name of certain compounds, and in the other one the properties of each compounds. So I want to merge them to have for each compound name the relative properties. ...
4
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1answer
147 views

Passing values from a list to Select during a Dataset query

Given a Dataset: ...
4
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1answer
117 views

DeleteMissing doesn't match in Association tables

DeleteMissing doesn't work in Association tables: ...
4
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2answers
201 views

Using GatherBy with a DataSet's header designation instead of First

Using the code, where ds is data formatted into a Dataset GroupBy[ds, First] // TableForm I get a table that I wanted, but I was wondering if I could somehow use ...
4
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1answer
148 views

Casting Dataset internal type from Assoc to Struct

Using: planets = ExampleData[{"Dataset", "Planets"}]; The full form of this projection displays the internal type def: ...
4
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1answer
67 views

Inconsistency in getting Keys, Values and Query for nested Rules

Querying nested Rule expressions of the form a -> v -> b // FullForm Rule[a,Rule[v,b]] for ...
4
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2answers
62 views

Simple dataset query

Why does taking a Part fail in a Dataset query function when there is an operation in the index argument? ...
4
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2answers
707 views

Change value in a Dataset

I could not find an answer on this fundamental question, even though I was reading the references on Dataset and Association and ...
4
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1answer
266 views

Applying different functions to Dataset columns after GroupBy

I have a list of associations dataset. ...
4
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1answer
59 views

How do I import a Dataset that contains lists?

The very first example in the Dataset documentation is the following: ...
4
votes
1answer
65 views

Operator form for Histogram of multiple datasets?

I would like to plot a histogram for multiple datasets in a dataset query, but can't quite seem to make it work in operator notation: ...
4
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1answer
87 views

Replacing “Unmatched” with value

I have two datasets ...
4
votes
1answer
331 views

How to Operate on a Dynamic Dataset?

I cannot operate on the Dataset I am dynamically filtering. Minimal example follows. ...
4
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1answer
136 views

Upvalues for Missing do not work with Dataset

Consider the following Dataset: d = Dataset[<| 1 -> Missing[], 2 -> 1.0, 3 -> 4.0 |>] And the following Upvalue for Missing: ...
4
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1answer
191 views

Extraction of rows with even numbers of a dataset

...
4
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1answer
260 views

Query Dataset to check if row contains any from a set of values

For a given keyless dataset, I can query to return the rows whose columns contain a specific value. For example: ...
4
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2answers
350 views

GroupBy and MaximalBy to create a new Dataset

I'm looking for a neater way to achieve this, which to me looks awkward and suggests that I am missing something... Given a Dataset... ...
4
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3answers
311 views

How to generate and label multiple histograms as Query operator(s)?

The Dataset documentation doesn't indicate how to label a Histogram with the key. ...
4
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1answer
196 views

Why is there a lot of noise in the Wolfram Blockchain?

I tried to look into the transaction history of the Wolfram Blockchain. I tried this:- ...