mdcfrancis

4년 전discuss

The authors of the encoding/json library thought the same. As a way to exit from deep down in a parse stack it works well especially if you only have limited entry points. https://cs.opensource.google/go/go/+/refs/tags/go1.19:src/en... uses well typed panics.

mdcfrancis

4년 전discuss

Amazon WorkMail, part of the AWS suite of tools, $4/month/user last I looked. If you host your domain on route53 setup is painless. It's an exchange server compatible service and provides some MDM functionality.

mdcfrancis

5년 전discuss

I can answer for the type stable julia case, if you have a struct in julia that is composed only of primitive types this is stored as a C struct with zero overhead and fixed byte length. An array of these is then crazy efficient when it comes to streaming into the CPU etc. If you dig around the GPU support in Julia you can see this used to good effect.

mdcfrancis

5년 전discuss

unfortunately, I don't have access to that code anymore, I wrote a number of loaders for different data set types including CSV. The time series were all modeled as forward iterating stream of tuples, so there is no specific table abstraction. There is an implicit assumption that the stream is ordered by the join key, in a time series this being the timestamp, though nothing in the implementation enforced that.

Joins are always n-way merge joins, so you can write something like y = 2x^2 - 3z + c and fold that into a single streaming operation y = f( x, z, c ) where y, x, z and c are time streams.

When rendered to screen they looked very similar to your examples. With plugins in the IDE you could directly plot and array of time series as a chart.

Since the time I wrote NamedTuples the Julia core team folded the functionality into the core of Julia https://docs.julialang.org/en/v1/manual/types/#Named-Tuple-T.... This is the core of https://juliadb.org/ all credit to the Julia core team

mdcfrancis

5년 전discuss

I've written similar in Julia, you can see the record type used in https://www.juliapackages.com/p/namedtuples. The full library, not in the open source, uses this type for time series analysis. It's all type safe and allowed expressions such as x = vwap( ts, 5) - l1( vwap( ts, 5)) through to a time moving PCA. Julia makes writing this sort of thing short and quick. The total impl was only a thousand lines or so of code.

mdcfrancis

5년 전discuss

they are also, type stable, strongly typed and have the same overhead as a struct. So an array of NamedTuples takes the minimal space and allocation.

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