Re: Convert Binary Image to Column Vector
- To: mathgroup at smc.vnet.net
- Subject: [mg83977] Re: Convert Binary Image to Column Vector
- From: Szabolcs Horvát <szhorvat at gmail.com>
- Date: Thu, 6 Dec 2007 02:38:31 -0500 (EST)
- References: <fj65hr$fp1$1@smc.vnet.net>
Tara.Ann.Lorenz at gmail.com wrote:
> Can a 30x30 binary image be converted directly into a column vector of
> 900 components in Mathematica?
It depends on what you mean by "image",
> Or must the image first be put into
> matrix form?
and what you mean by "matrix".
> I am using the command:
> Flatten@Transpose@t1,
This command works if t1 is a two-dimensional array, i.e. a nested list
that looks like this when output is set to StandardForm:
{{1,2},{3,4}}
> where t1 is my binary image, and it seems to
> give me a vector but I'm not sure if it's the one that I desire.
>
> If I first convert my image into matrix form
How did you do this conversion? If the image is inside
Graphics[Raster[...]], then you need to extract the contents of Raster[...].
> and define my matrix as
> "m" and then use this command,
> Flatten@Transpose@m, then I get an output of "Transpose[...]" and my
> 30 x 30 matrix is explicitly written within the Transpose brackets.
> This does not provide me a column vector with 900 components, which is
> what I am looking for.
In Mathematica there are no column or row vectors, only vectors and
matrices (one might call n*1 matrices column vectors and 1*n matrices
row vectors). Have you read the post I suggested in my answer to you
last question?
Here's the link again:
http://groups.google.com/group/comp.soft-sys.math.mathematica/browse_thread/thread/24fa2f19317734fa/69770c22c257ca29#69770c22c257ca29
If you use TraditionalForm output, try switching to StandardForm for a
while to better understand how matrices/vectors are represented.
Szabolcs