[R] Pixel Image Reshaping using R

[Paul Bernal]

Thank you dear Sarah.

Have a great day!

El El jue, 24 de feb. de 2022 a la(s) 12:03 p. m., Sarah Goslee <
sarah.goslee using gmail.com> escribió:

> Hi Paul,
>
> I may be missing something, but you can transform a vector to a matrix
> of any desired size by using matrix().
>
> For more nuanced processing of images, you might look into one of the
> many image processing packages in R, or even the raster package (or
> the newer terra).
>
> Sarah
>
> On Thu, Feb 24, 2022 at 11:00 AM Paul Bernal <paulbernal07 using gmail.com>
> wrote:
> >
> > Dear friends,
> >
> > I apologize if the description is  a bit long, but I think that I need to
> > be as specific as possible so that you guys can help.
> >
> > I wil share with you a file (train.csv), which contains gray-scale images
> > of hand-drawn digits, from zero through 9.
> >
> > Each image is 28 pixels in height and 28 pixels in width, for a total of
> > 784 pixels in total. Each pixel has a single pixel-value associated with
> > it, indicating the lightness or darkness of that pixel, with higher
> numbers
> > meaning darker. This pixel-value is an integer between 0 and 255,
> > inclusive. The training data set, (train.csv), has 785 columns. The first
> > column, called ”label”, is the digit that was drawn by the user. The rest
> > of the columns contain the pixel-values of the associated image. Each
> pixel
> > column in the training set has a name like pixel x, where x is an integer
> > between 0 and 783, inclusive. To locate this pixel on the image, suppose
> > that we have decomposed x as x = i ∗ 28 + j, where i and j are integers
> > between 0 and 27, inclusive. Then pixel x is located on row i and column
> j
> > of a 28 x 28 matrix, (indexing by zero). or example, pixel 31 indicates
> the
> > pixel that is in the fourth column from the left, and the second row from
> > the top, as in the ascii-diagram below.
> >
> >   This data is set up in a csv file which will require the reshaping of
> the
> > data to be 28 × 28 matrix representing images. There are 42000 images in
> > the train.csv file. For this problem it is only necessary to process
> > approximately 100 images, 10 each of the numbers from 0 through 9. The
> goal
> > is to learn how to generate features from images using transforms and
> first
> > order statistics.
> >
> > So I need to develop an algorithm to store the data in a data structure
> > such that the data is reshaped into a matrix of size 28 x 28 and then I
> > have to plot the developed matrix for indices 1, 2, 4, 7, 8, 9, 11. 12,
> 17
> > and 22.
> >
> > I have been looking for information about how to process this with R, but
> > have not found anything yet.
> >
> > The dataset is attached in this e-mail for your reference.
> >
> > Any help and/or guidance will be greatly appreciated.
> >
> > Best regards,
> > Paul
> >  train.csv
> > <
> https://drive.google.com/file/d/1WPb7bKHJ8BlzuLKJogMOAOqb-VCoXDMp/view?usp=drive_web
> >
> >
> >         [[alternative HTML version deleted]]
> >
> > ______________________________________________
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>
>
>
> --
> Sarah Goslee (she/her)
> http://www.sarahgoslee.com
>

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