# \#inmemorydatasets

**URL:** https://discourse.julialang.org/tag/inmemorydatasets/978.md

[Latest](https://discourse.julialang.org/latest.md) · [Categories](https://discourse.julialang.org/categories.md) · [Tags](https://discourse.julialang.org/tags.md)

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## [Seeking Insights: Tickerplants and Complex Event Processing (CEP) in Julia](https://discourse.julialang.org/t/seeking-insights-tickerplants-and-complex-event-processing-cep-in-julia/131980)

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**Author:** [@rohanshiloh](https://discourse.julialang.org/u/rohanshiloh)\
**Replies:** 4\
**Last updated:** [September 22, 2025, 9:54pm UTC](https://discourse.julialang.org/t/seeking-insights-tickerplants-and-complex-event-processing-cep-in-julia/131980 "2025-09-22T21:54:32Z")

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The functional programming language and time-series vector database q/KDB has a low-latency architecture for efficiently processing extremely large volumes of real-time financial data directly from exchanges like the NYS…

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## [Byrow function to get the mean of row](https://discourse.julialang.org/t/byrow-function-to-get-the-mean-of-row/102315)

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**Author:** [@raman\_kumar](https://discourse.julialang.org/u/raman_kumar)\
**Replies:** 10\
**Last updated:** [August 1, 2023, 12:20pm UTC](https://discourse.julialang.org/t/byrow-function-to-get-the-mean-of-row/102315 "2023-08-01T12:20:20Z")

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I want to get the row wise mean of two columns of data using byrow function. These two columns are T\_start(s) and T\_stop(s). How should i change code given below ? :point\_down: using HTTP,CSV,DataFrames,InMemoryData…

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## [Use joins to change country names](https://discourse.julialang.org/t/use-joins-to-change-country-names/97507)

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**Author:** [@akshdfyehd](https://discourse.julialang.org/u/akshdfyehd)\
**Replies:** 7\
**Last updated:** [April 23, 2023, 6:37am UTC](https://discourse.julialang.org/t/use-joins-to-change-country-names/97507 "2023-04-23T06:37:47Z")

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Hi, I have got a dataset with a city and country column. However, there are some names in country column are actually the same place but different names, for example: row 7 and 123, I want both country name be Austra…

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## [Split country column into a column with city and a column with country](https://discourse.julialang.org/t/split-country-column-into-a-column-with-city-and-a-column-with-country/96586)

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**Author:** [@akshdfyehd](https://discourse.julialang.org/u/akshdfyehd)\
**Replies:** 5\
**Last updated:** [March 28, 2023, 10:57am UTC](https://discourse.julialang.org/t/split-country-column-into-a-column-with-city-and-a-column-with-country/96586 "2023-03-28T10:57:19Z")

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Hi, i have got a travel dataset and I need to split the destination column into two columns, one column is city and another column is country name, for example, “Sydney, Australia” will be split into sydney in city colum…

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## [How to change form using InMemoryDatasets package?](https://discourse.julialang.org/t/how-to-change-form-using-inmemorydatasets-package/95989)

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**Author:** [@akshdfyehd](https://discourse.julialang.org/u/akshdfyehd)\
**Replies:** 7\
**Last updated:** [March 16, 2023, 6:37am UTC](https://discourse.julialang.org/t/how-to-change-form-using-inmemorydatasets-package/95989 "2023-03-16T06:37:33Z")

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I’ve got a dataset from kaggle, which is relate to travel, and there is a column called “accommodation cost” which have some value like these: so there are three types, how to change the one with dollar sign and one …

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## [How to change the entire column form for different situation?](https://discourse.julialang.org/t/how-to-change-the-entire-column-form-for-different-situation/96037)

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**Author:** [@akshdfyehd](https://discourse.julialang.org/u/akshdfyehd)\
**Replies:** 2\
**Last updated:** [March 14, 2023, 3:28pm UTC](https://discourse.julialang.org/t/how-to-change-the-entire-column-form-for-different-situation/96037 "2023-03-14T15:28:20Z")

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Hi, I have got a dataset from kaggle and its relate to travel, Here are the link for raw datasets: https://raw.githubusercontent.com/akshdfyehd/travel/main/Travel%20details%20dataset.csv there is a column call “Destina…

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## [How to get average salary for each experience level for each job title?](https://discourse.julialang.org/t/how-to-get-average-salary-for-each-experience-level-for-each-job-title/91003)

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**Author:** [@akshdfyehd](https://discourse.julialang.org/u/akshdfyehd)\
**Replies:** 1\
**Last updated:** [November 29, 2022, 5:52pm UTC](https://discourse.julialang.org/t/how-to-get-average-salary-for-each-experience-level-for-each-job-title/91003 "2022-11-29T17:52:57Z")

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Hi, I got the dataset like following: I would like to get average salary for each experience level in each job title, I have tried: second=combine(groupby(new,:experience\_level,),:salary\_in\_usd =\>IMD.mean) but the…

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## [How to use filter from inmemorydatasets package](https://discourse.julialang.org/t/how-to-use-filter-from-inmemorydatasets-package/89696)

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**Author:** [@akshdfyehd](https://discourse.julialang.org/u/akshdfyehd)\
**Replies:** 3\
**Last updated:** [November 3, 2022, 11:24pm UTC](https://discourse.julialang.org/t/how-to-use-filter-from-inmemorydatasets-package/89696 "2022-11-03T23:24:04Z")

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Hi, I am looking for a way to extract all the rows that match PT from the column employment\_type, I have tried to change dataset into dataframe but there are still same errors, can anyone please give me some adv…

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## [How to take the average value for each type in the job title column?](https://discourse.julialang.org/t/how-to-take-the-average-value-for-each-type-in-the-job-title-column/89710)

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**Author:** [@akshdfyehd](https://discourse.julialang.org/u/akshdfyehd)\
**Replies:** 3\
**Last updated:** [November 3, 2022, 12:36pm UTC](https://discourse.julialang.org/t/how-to-take-the-average-value-for-each-type-in-the-job-title-column/89710 "2022-11-03T12:36:19Z")

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Hi, I have met the problem that for same employment type, there are different salary coressponding to the same job title, but I only need one salary value for one job title, can someone please give me some advices about …

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## [A preview of \`StatisticalGraphics\` a new package for data visualisation in Julia](https://discourse.julialang.org/t/a-preview-of-statisticalgraphics-a-new-package-for-data-visualisation-in-julia/89547)

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**Author:** [@sl-solution](https://discourse.julialang.org/u/sl-solution)\
**Replies:** 0\
**Last updated:** [October 31, 2022, 8:46am UTC](https://discourse.julialang.org/t/a-preview-of-statisticalgraphics-a-new-package-for-data-visualisation-in-julia/89547 "2022-10-31T08:46:26Z")

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I am very excited to share a preview of StatisticalGraphics, a package that I have developed for statistical data visualisation in Julia. The idea of the package is to develop a simple to use and yet powerful tool for st…

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## [How to change the country name and then draw the global map?](https://discourse.julialang.org/t/how-to-change-the-country-name-and-then-draw-the-global-map/88076)

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**Author:** [@akshdfyehd](https://discourse.julialang.org/u/akshdfyehd)\
**Replies:** 20\
**Last updated:** [October 7, 2022, 10:50am UTC](https://discourse.julialang.org/t/how-to-change-the-country-name-and-then-draw-the-global-map/88076 "2022-10-07T10:50:32Z")

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Hi, I got the dataset like following: I want to make a world map and see which country have higher mean salary, maybe represent through density or sth else, like density higher means the mean salary is higher, I tried…

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## [Why the current version of a document is not showing in the google search?](https://discourse.julialang.org/t/why-the-current-version-of-a-document-is-not-showing-in-the-google-search/87308)

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**Author:** [@ab2z](https://discourse.julialang.org/u/ab2z)\
**Replies:** 0\
**Last updated:** [September 15, 2022, 10:03am UTC](https://discourse.julialang.org/t/why-the-current-version-of-a-document-is-not-showing-in-the-google-search/87308 "2022-09-15T10:03:44Z")

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searching in google for the InMemoryDatasets has led me to the old version of the package InMemoryDatasets in the Juliahub. For the sake of user time saving, it would be suggested, if Juliahub always point to the latest…

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## [About examples in format validation from inmemorydatasets documents](https://discourse.julialang.org/t/about-examples-in-format-validation-from-inmemorydatasets-documents/86640)

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**Author:** [@akshdfyehd](https://discourse.julialang.org/u/akshdfyehd)\
**Replies:** 1\
**Last updated:** [September 13, 2022, 4:17am UTC](https://discourse.julialang.org/t/about-examples-in-format-validation-from-inmemorydatasets-documents/86640 "2022-09-13T04:17:16Z")

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Hi, I am relatively new to Julia, I can’t find the example for content inside red lines, can someone please make an example? How to show in Julia that changing the definition of the formats destroys the sorting order of …

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## [Byrow with user defined function](https://discourse.julialang.org/t/byrow-with-user-defined-function/79132)

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**Author:** [@monopolynomial](https://discourse.julialang.org/u/monopolynomial)\
**Replies:** 4\
**Last updated:** [May 1, 2022, 10:32am UTC](https://discourse.julialang.org/t/byrow-with-user-defined-function/79132 "2022-05-01T10:32:55Z")

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for data like ds=Dataset(x1=\[1,2,3\],x2=\[3,2,1\]) if I want to filter rows where x1 is less than x2 then this works filter(ds, :x1, type=isless, with = :x2) but when I define a function for byrow like f(x)=x\[1\]\< x\[2\] …

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## [How to combine prettytables and pager?](https://discourse.julialang.org/t/how-to-combine-prettytables-and-pager/85593)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 4\
**Last updated:** [August 11, 2022, 7:44am UTC](https://discourse.julialang.org/t/how-to-combine-prettytables-and-pager/85593 "2022-08-11T07:44:11Z")

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When using prettytables I have a lot of keyword options that I can use to display a pretty table. With the function pager from TerminalPager I can browse through a dataset that does not fit on the screen. How can I combi…

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## [Does InMemoryDatasets support the Tables interface?](https://discourse.julialang.org/t/does-inmemorydatasets-support-the-tables-interface/85457)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 1\
**Last updated:** [August 10, 2022, 2:19am UTC](https://discourse.julialang.org/t/does-inmemorydatasets-support-the-tables-interface/85457 "2022-08-10T02:19:05Z")

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See title. I wonder because it is not listed in Tables.jl/INTEGRATIONS.md at main · JuliaData/Tables.jl · GitHub .

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## [How to create columns in a loop](https://discourse.julialang.org/t/how-to-create-columns-in-a-loop/85519)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 6\
**Last updated:** [August 9, 2022, 8:02am UTC](https://discourse.julialang.org/t/how-to-create-columns-in-a-loop/85519 "2022-08-09T08:02:58Z")

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I have the following code: using InMemoryDatasets # create a demo data set of CAN bus messages function demo\_data() n = 100000 time = 0.1:0.1:n\*0.1 addr = rand(Int16(0x101):Int16(0x12e), n) d1 = rand(UI…

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## [Performance of creating a demo dataset](https://discourse.julialang.org/t/performance-of-creating-a-demo-dataset/85441)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 7\
**Last updated:** [August 8, 2022, 2:56am UTC](https://discourse.julialang.org/t/performance-of-creating-a-demo-dataset/85441 "2022-08-08T02:56:38Z")

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I have the following code: using InMemoryDatasets function demo\_data() ds = Dataset(time=0.0, d1=10, d2=20, d3=30) time = 0.1 for i in 1:100000 if i == 5 d1 = missing else …

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## [How can I swap columns of InMemoryDatasets?](https://discourse.julialang.org/t/how-can-i-swap-columns-of-inmemorydatasets/84808)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 3\
**Last updated:** [August 5, 2022, 4:38am UTC](https://discourse.julialang.org/t/how-can-i-swap-columns-of-inmemorydatasets/84808 "2022-08-05T04:38:33Z")

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I have the following example: using InMemoryDatasets g1 = repeat(1:6, inner = 4); g2 = repeat(1:4, 6); y = \["d8888b. ", " .d8b. ", "d888888b ", " .d8b. ", "88 \`8D ", "d8' \`8b ", "\`~~88~~' ", " d8' \`…

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## [Nested groupby](https://discourse.julialang.org/t/nested-groupby/78958)

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**Author:** [@rocco\_sprmnt21](https://discourse.julialang.org/u/rocco_sprmnt21)\
**Replies:** 9\
**Last updated:** [July 23, 2022, 5:17am UTC](https://discourse.julialang.org/t/nested-groupby/78958 "2022-07-23T05:17:36Z")

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trying to understand the role of kwarg isgathered, I practiced this exercise. julia\> ds = Dataset(id = \[1,1,1,1,1,2,2,2,3,3,3\], date = Date.(\["2019-03-05", "2019-03-12", "2019-04-10", …

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## [How to filter InMemoryDatasets](https://discourse.julialang.org/t/how-to-filter-inmemorydatasets/83478)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 7\
**Last updated:** [July 23, 2022, 5:14am UTC](https://discourse.julialang.org/t/how-to-filter-inmemorydatasets/83478 "2022-07-23T05:14:31Z")

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Example: using InMemoryDatasets ds = Dataset(x1 = 1, x2 = 1:10, x3 = repeat(1:2, 5)) res = modify!(ds, :x2 =\> byrow(isodd) =\> :ODD) The output is; julia\> include("test/filter.jl") 10×4 Dataset Row │ x1 x2 …

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## [\[ANN\] DLMReader 0.4.5 with one Big Enhancement](https://discourse.julialang.org/t/ann-dlmreader-0-4-5-with-one-big-enhancement/83729)

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**Author:** [@sl-solution](https://discourse.julialang.org/u/sl-solution)\
**Replies:** 3\
**Last updated:** [July 11, 2022, 8:43am UTC](https://discourse.julialang.org/t/ann-dlmreader-0-4-5-with-one-big-enhancement/83729 "2022-07-11T08:43:22Z")

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I am excited to announce that DLMReader version 0.4.5 has been released. The new release includes several performance enhancements and bug fixes. For instance, reading multiple observations per line and type detecting ar…

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## [\[ANN\] A new lightning fast package for data manipulation in pure Julia](https://discourse.julialang.org/t/ann-a-new-lightning-fast-package-for-data-manipulation-in-pure-julia/78197)

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**Author:** [@sl-solution](https://discourse.julialang.org/u/sl-solution)\
**Replies:** 94\
**Last updated:** [July 4, 2022, 5:31am UTC](https://discourse.julialang.org/t/ann-a-new-lightning-fast-package-for-data-manipulation-in-pure-julia/78197 "2022-07-04T05:31:40Z")

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I am excited to announce a new package for data manipulation in pure Julia. Introduction InMemoryDatasets.jl is a multi-threaded package for data manipulation and is designed for Julia 1.6+ (64bit OS). The core computat…

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## [How to update a data set using another data set?](https://discourse.julialang.org/t/how-to-update-a-data-set-using-another-data-set/80203)

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**Author:** [@mostafa1342004](https://discourse.julialang.org/u/mostafa1342004)\
**Replies:** 5\
**Last updated:** [July 1, 2022, 9:30am UTC](https://discourse.julialang.org/t/how-to-update-a-data-set-using-another-data-set/80203 "2022-07-01T09:30:33Z")

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I have a master data set and I like to update some of its values using a transaction data set. There are some key columns for finding the rows that must be updated in both data sets. I know about update! function but the…

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## [How to pretty print an InMemoryDataset?](https://discourse.julialang.org/t/how-to-pretty-print-an-inmemorydataset/82909)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 2\
**Last updated:** [June 21, 2022, 4:02am UTC](https://discourse.julialang.org/t/how-to-pretty-print-an-inmemorydataset/82909 "2022-06-21T04:02:06Z")

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When I print an InMemoryDataSet, how can I suppress the lines: Row │ time RTR addr d1 d2 data3 data4 data5 data6 │ identity identity hex hex2 hex2 hex2 hex2 …

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## [\[ANN\] DLMReader: the most versatile Julia package for reading delimited files yet](https://discourse.julialang.org/t/ann-dlmreader-the-most-versatile-julia-package-for-reading-delimited-files-yet/81899)

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**Author:** [@sl-solution](https://discourse.julialang.org/u/sl-solution)\
**Replies:** 19\
**Last updated:** [June 9, 2022, 7:32am UTC](https://discourse.julialang.org/t/ann-dlmreader-the-most-versatile-julia-package-for-reading-delimited-files-yet/81899 "2022-06-09T07:32:26Z")

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I am excited to announce DLMReader, a Julia package for reading delimited files. Introduction DLMReader.jl is a multithreaded package for reading delimited files, and it is designed for Julia 1.6+ (64bit OS). The packag…

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## [How to find frequency count for consecutive actions?](https://discourse.julialang.org/t/how-to-find-frequency-count-for-consecutive-actions/78582)

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**Author:** [@xinchin](https://discourse.julialang.org/u/xinchin)\
**Replies:** 10\
**Last updated:** [May 1, 2022, 10:09am UTC](https://discourse.julialang.org/t/how-to-find-frequency-count-for-consecutive-actions/78582 "2022-05-01T10:09:09Z")

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I have a few sizable data sets with rows contains actions of a person in different days. I want to summarize the data as a frequency table that shows the number of times that a specific action followed by another action.…

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## [Compare 2 data sets - similar to SAS proc compare](https://discourse.julialang.org/t/compare-2-data-sets-similar-to-sas-proc-compare/79215)

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**Author:** [@ab2z](https://discourse.julialang.org/u/ab2z)\
**Replies:** 4\
**Last updated:** [April 11, 2022, 6:02pm UTC](https://discourse.julialang.org/t/compare-2-data-sets-similar-to-sas-proc-compare/79215 "2022-04-11T18:02:38Z")

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Question: what is the best command for comparing 2 datasets - something like proc compare in SAS ? I could not edit this Comparison 2 data sets , So I decide to open this new topic. I have the following example old=Da…

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## [Column types in DataFrames vs. InMemoryDatasets](https://discourse.julialang.org/t/column-types-in-dataframes-vs-inmemorydatasets/78682)

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**Author:** [@monopolynomial](https://discourse.julialang.org/u/monopolynomial)\
**Replies:** 6\
**Last updated:** [March 29, 2022, 2:55pm UTC](https://discourse.julialang.org/t/column-types-in-dataframes-vs-inmemorydatasets/78682 "2022-03-29T14:55:23Z")

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it’s very interesting, because it seems the following point is more about DataFrames.jl after all. because using InMemoryDatasets using NamedArrays initial = NamedArray(\[5748.61\], \["AUT-A01"\]) df\_initial = Dataset(:…

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## [Is \`InMemoryDatasets.create\_sysimage\` documented anywhere?](https://discourse.julialang.org/t/is-inmemorydatasets-create-sysimage-documented-anywhere/78246)

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**Author:** [@xinchin](https://discourse.julialang.org/u/xinchin)\
**Replies:** 4\
**Last updated:** [March 26, 2022, 11:10am UTC](https://discourse.julialang.org/t/is-inmemorydatasets-create-sysimage-documented-anywhere/78246 "2022-03-26T11:10:41Z")

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@sl-solution I see there’s a function in your package (not exported) and I think it is for creating sysimage? is it documented somewhere which I can look at?

[Next page](https://discourse.julialang.org/tag/inmemorydatasets/978.md?match_all_tags=true&page=1&tags%5B%5D=inmemorydatasets)