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asked How to lookup by a string key after GroupBy? Inconsistent data type handling
Aug
21
comment Export dataset to JSON
WRI focus too much on toy use cases in testing, eg currently useless SemanticImport: we have study filenames that start with Q - SemanticImport casts these values to an electrical unit, among other bizarre issues not worth fixing.
Aug
18
revised Simplifying a time-series segmentation Query
added 8 characters in body
Aug
18
asked Simplifying a time-series segmentation Query
Aug
15
reviewed Approve suggested edit on How can I add a tangent arrow at a certain point of a curve in a LogPlot?
Aug
14
comment Median of Dataset in Mathematica 10
@TaliesinBeynon, possibly related issue (same workaround): SplitBy also doesn't have an operator form. Reference page hasn't been updated for 10. Can you please report to WRI?
Aug
14
comment Adding an unused column creates an error in JoinAcross
JoinAcross doesn't take Dataset arguments, which is what your 2nd example suggests. Normal'ize.
Aug
12
comment How to split a Dataset into training and testing for machine learning?
I get an Accuracy = 0.63. Naive splitting like this is often biased by the dataset layout, eg, look at the distribution of "class": trainTit[Map[First] /* Counts, "Features"] --> "1st" -> 200 versus testTit[Map[First]...] --> "1st" -> 123, "2nd" -> 277, "3rd" -> 709. Typically, bootstrap or other resampling methods are used to minimize the effects of clustering. Certainly you'd want to randomize the partition.
Aug
11
comment How to change element color in Periodic Table?
@bobthechemist, btw, +1, not necessarily by color but any other visualization method, eg icons or other graphical markup. Also there seem to be alternative periodic tables and layouts, including spiral based. Jan Boeyens describes 4 tables in his Chemistry from First Principles. It would be nice to relate them.
Aug
11
comment How to change element color in Periodic Table?
@bobthechemist, can you find a way to display all or most of the features at the same time?
Aug
7
reviewed Approve suggested edit on Combining images with CUDA
Aug
6
comment Convert a list of rules into 2 lists of integers
{First[#], Last[#]} & /@ data // Transpose
Aug
4
awarded  Nice Question
Jul
31
revised How to group each element with each consecutive elements in one head
added 120 characters in body
Jul
31
revised How to group each element with each consecutive elements in one head
added 98 characters in body
Jul
31
comment How to group each element with each consecutive elements in one head
Long live Fortran?
Jul
31
answered How to group each element with each consecutive elements in one head
Jul
31
answered How to group each element with each consecutive elements in one head
Jul
31
accepted Operator syntax for Merge-like Query
Jul
31
comment Operator syntax for Merge-like Query
@Rojo, that works - I had tried {Query[Median],Query[Length]} but didn't think of this variation. Write it up as an answer, will accept.