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Sep
19
comment Transcendental equation Non-linear how to solve
Dear @user7096 - if you want to improve your question, please edit it using the "edit" link at the bottom of the question.
Sep
19
comment Taking a percentage of data from a list or a table
Top and bottom X% by length or by value? Consider TrimmedMean if that is what you are intending to calculate.
Sep
19
comment Taking a percentage of data from a list or a table
What if the rounded value Round[LengthofData*StartPercentage, 1] is 0? I think you need a few extra checks in here. I also don't think you need the final parameter - just let the function get the Length of the data directly. Otherwise you could have a last parameter that is not compatible with the data.
Sep
19
comment Autoregressive distributed lag model
If you mean distributed lags of exogenous variables, then you need to respecify the FoldList approach to have more than one element in each iterate of the list in the last argument.
Sep
18
comment Simplify vector expression - is there something like “Factor” for vectors, dot products etc.?
Dear physicslol, welcome to Mathematica.SE! Please don't post comments as answers, as it works against the Q&A and model of the site and can be unhelpful for future visitors. I've turned your answer into a proper comment.
Sep
18
comment Autoregressive distributed lag model
Please also see the "Related" questions shown in the sidebar to this question, particularly this one
Sep
17
comment Double series over primes
All, given the divided views on whether the question should be closed, I propose to give it the benefit of the doubt and leave it open. If a question has this many upvoted answers, it deserves to be left open.
Sep
17
comment Double series over primes
Chris' sis, whoever it was would like you to provide more details and ideally some Mathematica code.
Sep
17
comment Roads network visualization by thickness and color intensity by population from GIS files
Alex, this is an interesting question but it would help if you posted what you tried and where you got stuck.
Sep
11
comment How to capitalize the first letter of each word in a string
This isn't a separate answer, but it's worth knowing that "Title case" usually does not capitalize certain small words, so you'd do something like: replacelittlewords = z : (StartOfString | WhitespaceCharacter ~~ # ~~ WhitespaceCharacter) :> ToLowerCase[z] & /@ {"A", "An", "The", "Is", "On", "To"} and then StringReplace[ StringReplace["This is a test about which you will be amazed", z : (StartOfString | WhitespaceCharacter ~~ _) :> ToUpperCase[z]], replacelittlewords].
Sep
10
comment Relational joining of tables
@IanSchumacher - on the contrary - it is just that there are plenty of cases where people versed in other languages would reach for a loop, but vectorised or pattern-matching operations would be more efficient. See this question.
Sep
10
comment Relational joining of tables
Well, the question was written in terms of things with matching id's, so please forgive me that it was not clear to me that you had something more general in mind. But different criteria would suggest a different approach, including your Outer one.
Sep
10
comment Relational joining of tables
I think the difference is that this one (I think) assumes unique keys. At least that's what I understand a SQL table id to be.
Sep
8
comment Alternatives to procedural loops and iterating over lists in Mathematica
@d555 - not in this instance. The original poster had used a sequence of definitions, Xarray[some_Integer] rather than a vector with parts. Both approaches are possible in Mathematica.
Sep
5
comment Hodrick–Prescott filter (one-sided version)
@YvesKlett just be aware of some of the pitfalls of this filter. See, for example, Cogley T and JM Nason (1995), ‘Effects of the Hodrick-Prescott Filter on Trend and Difference Stationary Time Series: Implications for Business Cycle Research’, Journal of Economic Dynamics and Control, 19(1–2), pp 253–278.
Sep
4
comment Hodrick–Prescott filter (one-sided version)
@YvesKlett You're welcome - I thought the HP filter was used exclusively in economics?
Aug
28
comment Setting non-standard ImageResolution for EMF export as default
@RolfMertig because it won't be me doing it. It will be end users expecting the process to be at least as straightforward as the process they are currently using. If I can't deliver that, user acceptance could be affected.
Aug
28
comment Why is building a table of function values so much slower than just plotting the function?
You can save about one-third of the time by removing the redundant Evaluate from your Table expression. Also, this result is entirely dependent on the MaxRecursion setting. If you remove this, or leave it in but increase its value, the plot takes longer than the table.
Aug
27
comment How to make MapAt work with Span?
It also works with All, e.g. fakedailydata = Transpose@{DatePlus[{2001, 1}, #] & /@ Range[0, 999], Accumulate[RandomVariate[NormalDistribution[0, 1], {1000}]]}; MapAt[#^2 &, fakedailydata, {All, 2}]. Really handy for time series (date-value pairs).
Aug
19
comment Numbered equations/formulas
hi @earnric, welcome to Mathematica.SE! I have converted your "answer" to a comment because it didn't really address the question.