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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.

0
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0answers
38 views

Aggregate function problem

I use a function to do something similar to a SQL sum. I've asked about simplifying it in another post. I'm still using this function and it works well for aggregates like ...
2
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1answer
34 views

Filter rows in nested Association / Dataset using Select

The Dataset I am working with has the following nested structure. ...
1
vote
1answer
62 views

Problem importing from HDF5

I'm trying to import an item from a valid HDF5 file, but I get this error: I can read the metadata, but cannot import the actual tensor dataset: And yet it's not an issue with the file's data - as ...
4
votes
1answer
128 views

How to export a Dataset to JSON or CSV?

I am getting wolfram CDF format from this, ...
2
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1answer
49 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 ...
4
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1answer
46 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: ...
1
vote
1answer
109 views

How to make an Association of Assocations [closed]

As a learning exercise I’m trying to convert some data we have from spreadsheets into an association of associations. However, I’ve only managed to format two different associations, a key of the ...
10
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5answers
267 views

Select only first n elements in operator form?

Is there any way to make Select take a second argument (to select only the first n elems) while in operator form? It's too ...
3
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0answers
113 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:- ...
3
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0answers
38 views

How to find the block number of a transaction in a Wolfram Blockchain?

For example, in block 1004 of the Wolfram Blockchain, I can get the 4th transaction's ID by using the following code:- ...
5
votes
5answers
367 views

Vector operation on datasets

I have a dataset like: ...
3
votes
3answers
105 views

Simpler way to thread dataset values to each other

I have a relatively simple dataset that provides a list of values for a list of countries: ...
0
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0answers
30 views

Nested Dataset and the Query operator

Suppose I have the following Dataset, one of whose columns is a nested Dataset: ...
0
votes
1answer
41 views

How to combine 3D figure with LogLogPlot to produce 2D figure

I have (x,y,z) set of data and I want to combine 3D figure with LogLogPlot and to produce 2D figure ...
2
votes
1answer
35 views

Where is the folder storing the ResourceData files?

I wonder where would the file be stored in Windows when I use the function ResourceData. Since sometimes the data is quite large, I would like to have a look at the ...
6
votes
1answer
75 views

How to update values of particular keys efficiently

Say I have a list of Association, SeedRandom[45] test = Association[Table[i -> RandomInteger[30], {i, 6}]] <|1 -> 18, ...
3
votes
2answers
98 views

Need help charting school shootings by year and number of victims

For my school project I've decided to take some data from Wolfram. I have the dataset from Data Repository, and I want to create three BarCharts. The first one shows the highest number of fatalities. ...
3
votes
1answer
67 views

Replace Elements in a Dataset by rules

I've got a dataset with 100+ various columns. I want to change e.g. the values 0 and 1 in the first column with "male" and "female". In the second column i'd like to change the 0 and 1 with e.g. "...
5
votes
3answers
134 views

Convert Matrix into a long form Dataset

I would like to convert a matrix into a dataset. The structure of the matrix is: ...
1
vote
4answers
84 views

setting size of images which are result of TextRecognize

Im learning Mathematica and the Wolfram language for shot time by myself. Its a pain for me that many settings are somehow hidden. Now I spent hours to find solution for something I already did with ...
0
votes
2answers
111 views

Prepare a dataset in Excel then import to Mathematica

I need to prepare a dataset, which will be much easier using e.g. Excel. Then I want to import and use it in Mathematica. One row in the dataset would look like this in Mathematica: ...
2
votes
1answer
32 views

Problem with Select using a Part [duplicate]

I have the following dataset: ...
0
votes
1answer
48 views

Export data of a function of 3 variables

I have a function like this ...
1
vote
1answer
76 views

Dynamically update of Association

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: ...
1
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0answers
58 views

What is a good way to store TimeSeries objects?

This is a question about proper ways to save and retrieve TimeSeries. I am processing data from two separate sources and compile around 150 ...
1
vote
2answers
94 views

Select several values in nested associations

I have nested associations like this: ...
9
votes
1answer
89 views

JoinAcross datasets based on Equal and not on SameQ

JoinAcross will join keys if values are the same (SameQ==True) but not if there are equal. For example these two associations are not joined : ...
1
vote
1answer
156 views

Export DataSet as CSV or XLS

One question: How can I export a DataSet to CSV and XLS ? ...
2
votes
1answer
94 views

ListPlot from DataSet

Let's say that I have the following Dataset: ...
1
vote
2answers
54 views

Extract values from a string list with string elements like “ Id=\”1\“ ”

I have a simple problem which I am not able to work around. I have this list ...
7
votes
1answer
142 views

Operating on datasets that have been grouped based upon multiple criteria

I have a dataset tds that can be represented by the following code: ...
0
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0answers
26 views

combined time-series plot from time-series dataset [duplicate]

I want to make a DateListPlot showing multiple series from a Dataset (ds). Each row of the ...
0
votes
0answers
69 views

Import Stackoverflow data and convert it into dataset

I have an xml file with the tag data from Stackexchange: https://archive.org/download/stackexchange/stackoverflow.com-Tags.7z After I unzip it I would like to import it to Mathematica to some ...
3
votes
4answers
180 views

Build a Frequency Table from a Dataset

How can the Mathematica 11.3 module below be improved (it builds a frequency table)? The data source is a Dataset object (dbase) and the row/column variables are respectively rowDIN and colDIN. Here ...
18
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0answers
145 views

Inefficient memory storage for Dataset

Why Dataset doesn't serialize its contents, isn't it the whole point? I expect it to behave similar to python's pandas.DataFrame,...
0
votes
1answer
51 views

Truncation of Labels and Data when visualized as Dataset

In the process of editing and manipulating web-derived data I am using Mathematica to assist in editing of tabular data entries. In my case the, data are served as Excel xls files that can be readily ...
1
vote
1answer
45 views

separating a `ReadList` of a CSV file into columns using `Case`

I have a really large file and would like to determine the pattern required for separating the columns by the different headers. I attempted to use Cases but it's ...
12
votes
5answers
243 views

Best way to convert numerical columns of a dataset with missing values into a matrix

What is the best way (simplest, fastest) to convert the numerical columns of a dataset into a matrix? The numerical columns can have missing values. For example for this dataset: ...
2
votes
0answers
75 views

`Transpose` nested `Association`

Say I have a nested Association like this one: ...
1
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0answers
54 views

How to: `GeneralizedLinearModelFit` with `Dataset` with cofactors

Please do not think of this question as a more general extension of LinearModelFit with Dataset asked by @alan, and answered by @Weach. The original question (or at least the solution) pertained more ...
3
votes
3answers
153 views

How to ListPlot two datasets on the same graph?

Consider the following dataset: keys = {"a", "b", "c", "d"}; vals = Partition[Range[20], 5] ds = Dataset[AssociationThread[keys, #] & /@ Transpose@vals] In ...
2
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3answers
104 views

Conditional selection of rows from a dataset

How can one select rows "a" and "b" from the following dataset where "b" values are larger ...
3
votes
1answer
50 views

Dataset column stubs in query result

Suppose I have a dataset with a header row. ds = Dataset[AssociationThread[{"x", "y", "z"}, #] & /@ RandomReal[{0, 1}, {10, 3}]]; I want to construct the ...
3
votes
3answers
122 views

aggregate records across dates

Each record in a dataset includes a country name, a year, and observations (e.g., GDP) for that country in that year. I would like to generate a new dataset with one record per country (so I would ...
1
vote
1answer
85 views

Take data point from Circle

I would like to draw a circle within triangle. In this case, I make it from 3 points. then I followed program below: ...
4
votes
3answers
126 views

Dataset query for keys of upper levels

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 ...
0
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0answers
38 views

Load tiles from folders for neural network

I would like to initialize a net with some images/tiles classified like this: ...
0
votes
1answer
113 views

How to create and implement a small database on Mathematica?

I have a function f[x_,y_,z_]:= a^x b^y c^z and I want to evaluate it for various values of x,y,z always coming in triples. This means I have a database with ...
5
votes
1answer
91 views

General question about data management

I am curating a small number of databases-actually I am not sure if they qualify as such; they are more like collections of-loosely-related data points; the problem is that they are growing over time; ...
7
votes
2answers
198 views

Map Values in 'nested' association

JSON often returns sort of 'nested' associations like so: ...