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.

Filter by
Sorted by
Tagged with
3
votes
1answer
399 views

Using a dataset of PredictorFunctions

I have been working with a dataset of predictor functions -- mainly so I can have more insight in to what the functions are doing and how they behave. Where I am struggling is using ...
3
votes
1answer
327 views

How to compare Histogram Data?

I'm using a Dataset ...
3
votes
1answer
58 views

Calculations on columns (column by column) in Dataset

Dataset from doc: ...
3
votes
1answer
71 views

What's the best way to import such dataset?

https://www.ocr.org.uk/Images/400305-large-data-set-lds_1-h630-2018-h640-2018-2019-pre-release-data-mei.xlsx What's the best way to import such dataset? I have tried to use ...
3
votes
1answer
70 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
2answers
129 views

Composition with Transpose failure with Dataset

Is the failure of the 2nd Transpose here a known bug? Dataset[{{0, 10}, {2, 11}, {3, 12}}][ Transpose /* Map[MinMax] /* Transpose] // Normal ...
3
votes
1answer
90 views

Evaluating same expression twice gives two distinct answers. Problem with Dataset?

Bug present in 10.4.1 and fixed in 11.0.1 Consider the following Dataset: d = Dataset[<|1 -> Missing[], 2 -> 2.0|>] Now evaluate ...
3
votes
1answer
169 views

Duplicate rows with multiple entries

I have a huge dataset, which looks similar to this: ...
3
votes
2answers
156 views

How can I join some values in rows to be value columns in a dataset/association

...
3
votes
1answer
882 views

Applying a function to a column of a dataset [closed]

Functions can easily be applied to columns of datasets, as in the documentation it is shown. Now I want to apply a function with parameters to a column, but I get a list rules. E.g. ...
3
votes
1answer
1k views

How to filter a dataset using Select and a parameter

I'd like to filter a Dataset using a parameter in Select, but so far I haven't been able to make it work properly. Say that I ...
3
votes
2answers
169 views

KeyMap on a flat Dataset (i.e. Dataset@Association)

Bug introduced in 10.0.0 and fixed in 10.1 See Kuba's anwser below for the bug. Dataset is new in 10.0.0. How can I go from ...
3
votes
1answer
97 views

TakeList of a Dataset

Check this out I want to split the Dataset for graphical reasons, like creating a nice composition on a page, TakeList should ...
3
votes
1answer
117 views

Simple dataset query fails

This is really weird. I can get the first row and a specific column from my Dataset, but when I try to get them both, I receive a cryptic error. What in the world could it be talking about. myData ...
3
votes
1answer
121 views

Single argument operator form?

I've heard the explanation that functions like StringDrop[] are varargs and so that is why they do not have an operator form. But when you are only using the ...
3
votes
1answer
76 views

Elegant way to return first non-Missing column in Dataset

I have a Dataset[] with some data and a TON of columns. Each row contains several columns for dates, which contain DateObject ...
3
votes
1answer
106 views

ID Swapping: Efficient use of a reference table to convert ID values

Context The rise of various bio-companies for high-throughput sequencing technology and open-source bioinformatic software suites for analysis thereof, has resulted in a equivalent rise of reference ...
3
votes
1answer
271 views

Add columns with dummies and specific headers to dataset

I got a dataset that looks like the following example: ...
3
votes
1answer
92 views

Do Dataset functions get applied to rows in order?

If I have a dataset ds and perform an operation such as ds[All, f] does f get applied in the order the rows exist (the order they were placed into the dataset or as the result of a SortBy clause) or ...
3
votes
1answer
252 views

How can I export dataset to excel with names

...
3
votes
0answers
37 views

How to implement with Rlink and RFunction the mblm non parametric regression library in R

See (https://cran.r-project.org/web/packages/mblm/index.html) I would imagine this could be done analoge to a blog from 2013 by Jon Mcloone (https://blog.wolfram.com/2013/05/22/why-would-a-...
3
votes
0answers
120 views

Adjusting opacity in map overlays

I am currently working with rainfall data from hurricane Harvey in order to better understand how to allocate resources in the event of another disaster. I want to accomplish a few things given this ...
3
votes
0answers
59 views

Aligning input form of a sequence of Queries

Is there a way to modify the parser, or define options, to align the indentation of a sequence of Queries on a Dataset? Given: ds = <|"a" -> 1, "b" -> <|"c" -> 2|>, "d" -> <|"e" -> 3, "f" ...
3
votes
0answers
108 views

JoinAcross for large Datasets [closed]

When running JoinAcross for larger datasets (lists of associations, ~100k lines, >100 columns) in Mathematica 10.1 I get the following behaviour: ...
3
votes
0answers
75 views

What's inside Dataset? [duplicate]

It seems that Dataset has rich structures in them, for example: ds = Dataset[{<|"a" -> 1, "b" -> "x", "c" -> {1}|>}]; TreeForm[dataset] Could you ...
3
votes
0answers
84 views

Map level inconsistencies with Missing values [closed]

Negative Level specs interact with Missing values, eg: ...
3
votes
0answers
89 views

Data Interpolation of deaths by date

I am working with an ebola dataset from Guinea, 2014:(http://currents.plos.org/outbreaks/article/estimating-the-reproduction-number-of-zaire-ebolavirus-ebov-during-the-2014-outbreak-in-west-africa/). ...
3
votes
0answers
182 views

Dataset fails to present data in some instances when inserting new data

Update: I solved the problem: the error will occur when the length of an association is less than the length of the longest association in the association of associations In my original problem I ...
3
votes
0answers
91 views

Export to MX seems to corrupt the in-memory Dataset

I have a function that does a large number of calculations (by calling out to other smaller functions), and then builds a large Dataset object. Then I do two ...
3
votes
0answers
274 views

Combining key pivoting and lookup operators in Dataset

This question is related to this one re pivoting on keys. Because of the nesting, using Leonid's method as starting point - single key: ...
2
votes
3answers
75 views

Select specific rows of a dataset

I am struggling with extracting specific rows from a dataset. ...
2
votes
6answers
3k views

Converting CSV data to a Dataset

I have data in a csv file. The first row has labels, and the first column, too. Datos = Import["C:\\Users\\jodom\\Desktop\\Data.csv"] Tha data in the csv file is ...
2
votes
1answer
180 views

Query and Dataset Syntax Peculiarities

Question Can someone please explain to me the syntax of Query and why its behavior is so befuddling to me at the moment? I am going to go through a few simple ...
2
votes
1answer
154 views

Deleting missing values from a dataset

I wanted to create a dataset of all UFO sightings in April of 2018. The AssociationThread doesn't want to work, because some of the entries are missing value, what ...
2
votes
3answers
129 views

ScientificForm in Dataset

Via SQL query I produce a list ...
2
votes
1answer
67 views

TakeLargestBy nested variable in Dataset

I would like to TakeLargestBy a nested variable in a Dataset. To be clearer, here is code to make an example dataset ...
2
votes
2answers
217 views

Group Datasets and take minimum/maximum

Good Morning I have the following dataset: And I try to reach this output: key: only one row per key text: join all texts of the rows with the same key (but no duplicates) min: take the lowest ...
2
votes
2answers
76 views

How to get company dataset in original currency?

I have obtained the financial data of a company using Entity["Company", ...]["Dataset"]: ...
2
votes
4answers
153 views

Import two variable data from excel

I'm quite new to Mathematica. I've been looking for the information but couldn't find it. I have several sets of data corresponding to the exposure of photographic paper. On the first row I have the ...
2
votes
1answer
129 views

How to format the output of GroupBy in a Dataset

Suppose I have a dataset titanic = Uncompress[FromCharacterCode[ Flatten[ImageData[Import["http://i.stack.imgur.com/sd05e.png"],"Byte"]]]] This two ...
2
votes
1answer
108 views

How can I code markers for different groups' values over a period of time?

I have a 3-column dataset where I show the probabilities of winning of teams in different years (team name, year, prob.) I need to plot it with markers so the probabilities of each team can be ...
2
votes
2answers
632 views

Classifying images in mass with URLs and CSV file

I'm looking to train a image classifier with a large number of examples and categories (30,000 & 100). I would then import a file of image URLs that need to be classified, and export the results. ...
2
votes
1answer
142 views

How can empty fields in a csv file be set to Missing when importing as a Dataset?

When importing a csv file with empty fields as a Dataset, the empty fields are set to zero-length strings (""). There is an option, ...
2
votes
3answers
158 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 ...
2
votes
1answer
95 views

Percentage of keys that match a criteria in a dataset [duplicate]

I have dataset designed around a whiskey tasting. I have 25 tasters who have submitted scores on about 20 whiskeys. Here is a sample of how I structured the data in Mathematica: ...
2
votes
1answer
215 views

Filtering of a Dataset based on a column name with underscore and a nested string pattern

I have the following dataset : ...
2
votes
1answer
41 views

Interpolating and subtracting two sets of data

I have a data set "data9k" with x varying from 0 to 365, and another data "data0" set with x varying from 0 to 365. But the x values for both data sets are not same but similar. I want to subtract the ...
2
votes
1answer
68 views

Sort Dataset by Row index after GroupBy

I would like to sort my Dataset by its row index. Unlike an ordinary column, this index does not have a name. ...
2
votes
1answer
97 views

Scraping 2020 Polling Data w/Mathematica?

Is there a way to use Mathematica to scrub the latest ("RCP average") polling data for each of the 2020 Democratic Primary candidates?
2
votes
1answer
90 views

How to set up SortBy columns in Dataset dynamically?

Given a dataset like this: ...