conceptoriented

6 tahun yang laludiscuss

> the mapping absolutely isn’t mutable

Assume f: X -> Y. We can now map x_1 to y_1 f(x_1)=y_1. And then change this same function by mapping x_1 to y_2: f(x_1)=y_2. Thus we can easily modify functions. Moreover, we do it constantly when we modify object fields in OOP. It is probably easier to comprehend if a function is represented as a table which we modify.

In contrast, we cannot modify data values (mathematical tuples). Say, x=42+1 means that a new value 43 is created rather than the existing value 42 is modified.

> I would expect the domain and codomain to be immutable;

No. Domains, codomains and any set can well be modified by adding or removing tuples. What is immutable are values (in the sets).

conceptoriented

6 tahun yang laludiscuss

Function is a mapping between two sets (of values). This mapping between values is mutable although the values are not.

conceptoriented

6 tahun yang laludiscuss

> Data never changes, but we have the possibility to create a new version of the data.

Well, it depends on what you mean by data. To avoid ambiguity it is better to talk about data values and data objects which have different properties. This can be formalized as follows [1]:

o data values are modelled via mathematical tuples – tuples are immutable

o data objects are modelled via mathematical functions (one field is a function from this reference to the field value) - functions are supposed to be mutable

(In reality of course we meet quite different situations, for example, struct is mutable and objects can be immutable.)

[1] Concept-oriented model: Modeling and processing data using functions https://www.researchgate.net/publication/337336089_Concept-o...

conceptoriented

6 tahun yang laludiscuss

I agree that data modeling is underestimated but it hardly can be considered a solved problem. It is very hard because there are numerous alternative understandings and formal defs of what we mean by data (RM, 00, OR, MD etc.) In additiin, there are several levels of representation (physical, logical, semantic). In real projects, they all are mixed.

conceptoriented

6 tahun yang laludiscuss

The concept-oriented model tries to overcome some problems of RM by relying on two constructs: sets and functions. In contrast, RM uses only sets. The idea is that data can be stored in functions and transformed via operations with functions.

(0) https://www.researchgate.net/publication/337336089_Concept-o...

conceptoriented

8 tahun yang laludiscuss

> it is pretty much completely inappropriate for production since it uses no vector instructions nor GPU computation

Many platforms do not have GPUs or special instructions, for example, at the edge.

conceptoriented

9 tahun yang laludiscuss

To test a machine learning algorithm, one can use "Fashion-MNIST": https://github.com/zalandoresearch/fashion-mnist

"Fashion-MNIST is a dataset of Zalando's article images—consisting of a training set of 60,000 examples and a test set of 10,000 examples. Each example is a 28x28 grayscale image, associated with a label from 10 classes. We intend Fashion-MNIST to serve as a direct drop-in replacement for the original MNIST dataset for benchmarking machine learning algorithms. It shares the same image size and structure of training and testing splits."

conceptoriented

9 tahun yang laludiscuss

thanks!

conceptoriented

9 tahun yang laludiscuss

> Coda is a next-generation spreadsheet designed to make Excel a thing of the past

There are many projects aimed at making Excel "a thing of the past" but they focus on different needs:

o https://airtable.com - use tables for data organization (organize anything)

o https://fieldbook.com - spreadsheet as a database

o https://www.rowshare.com share data (share rows, not data)

o http://conceptoriented.com - data transformations and data wrangling (I am the author)

o Coda - integration with documents

It is interesting if one of these approaches will eventually dominate or we will have a zoo of spreadsheet-like applications.

conceptoriented

9 tahun yang laludiscuss

From this (and many other) tutorial it is not clear if tensors in tensorflow are true mathematical tensors (that is, having covariant and contravariant indices) or they are multidimensional arrays. The name Tensorflow and terminology suggests that Tensorflow manipulates mathematical tensors, for example:

  Scalars -> Vectors -> Matrices -> Tensors (really tensors?)

but what you see are multidimensional arrays. It is of course not a big problem but probably could be clarified somewhere at least in small font to avoid ambiguity. Or Tensorflow objects are true tensors indeed?

conceptoriented

9 tahun yang laludiscuss

The lifetime word limit is a too rigid constraint. There should be a possibility to acquire (or lose) the points you can later use for publishing your results. Then the "price" of publishing negative results could be lower than other results.

conceptoriented

9 tahun yang laludiscuss

HPAT looks pretty promising. I wonder how they managed to signficantly increase performance of shuffling and sorting which are known to be quite difficult operations in map-reduce.

conceptoriented

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