Actually this is a better test to see how a color image looks when converted
to grayscale.
load 'viewmat'
PAL=:6 3$0 0 255 0 255 255 0 255 0 255 255 0 255 0 0 255 0 255
HUES=:>"0:;:'BLUE AQUA GREEN YELLOW RED MAGENTA'
PAL;HUES
RGB=:( #:i.8){0 255
ALL=:>"0:;:'BLACK BLUE GREEN AQUA RED MAGENTA YELLOW WHITE'
RGB;ALL
GRB=:1 0 2{"1 RGB
NEW=:>"0;: 'BLACK BLUE RED MAGENTA GREEN AQUA YELLOW WHITE'
GRB;NEW
(PAL;HUES);(RGB;ALL);<GRB;NEW
at2=: 13 :'([:{:"1 *.) j./"1 y'
D=:at2"0 /~ i:300
ro=: 13 :'<.0.5+y'
we=: 13 :'+/"1[0.3 0.59 0.11*"1 y'
gray=: 13 :'3#"0 ro we y'
(gray GRB) viewmat D;'gray GRB'
GRB viewmat D;'GRB'
(gray RGB) viewmat D;'gray RGB'
RGB viewmat D;'RGB'
(gray PAL) viewmat D;'gray PAL'
PAL viewmat D;'PAL'
E=:at2"0 /~ i:4
(gray GRB) viewmat E
(gray RGB) viewmat E
(gray PAL) viewmat E
GRB viewmat E;'GRB'
RGB viewmat E;'RGB'
PAL viewmat E
It uss a numerical file from Cliff Reiter. The grayscale looks like the
face of a clock. It shades from light to dark. Now use your palette to
view the at2 file andsee how it looks compared to the grayscale. I have
been happiest with GRB as a palette. It arranges the colors of light from
light to dark.
Linda
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Linda Alvord
Sent: Wednesday, November 12, 2014 11:33 AM
To: [email protected]
Subject: Re: [Jprogramming] greyscale viewmat
Here's the best I've come up with so far to take a numeric image and view it
in GRB color and then determine where smallest to largest numbers are in the
numeric array.
I am just finishing the narrated version in a dodx file which I hope to put
in dropbox soon. Maybe this will help
Cut, Paste and run in JHS or jqt but they appear and act quite differently:
NB.J TECH Grade 2 Summary Cod
load 'viewmat'
GRB=:1 0 2{"1 (#:i.8){0 255
rpt=: 13 :'(A=:x?x) + / B=:y?y'
rptable=: 13 :'(A=:x?x) + table B=:y?y' -
eb=: 13 :'y $<'' '''
boxes=: 13 :'([:<eb)"1 >"0 <"1 (>:i.x),"0 / >:i.y'
i.4
>:i.4
i. 21
|.i.21
(i.5) + table i.6
+ table i.4
]A=:11
]B=:i.11
+ table B
]A=:B + / B
]C=:+ / ~ B
C-:A
GRB viewmat C
GRB viewmat C;'Plus'
(10+B) - table B
]D=:(10+B)-/ B
GRB viewmat D;'Minus'
<. table ~ i.11
>.table ~ i.11
]E=: <. / ~ i.11
GRB viewmat E;'Lesser Of'
]F=:>. / ~ i.11
GRB viewmat F;'Larger Of'
5?5
rptable=: 13 :'(G=:x?x) + table H=:y?y'
5 rptable 7
G
H
rpt=: 13 :'(G=:x?x) + / H=:y?y'
I=:11 rpt 11
G
H
G + / H
GRB viewmat I;'Random Table'
]I=:11 rpt 11
G
H
G + / H
GRB viewmat I;'Random Table'
J=:'Anne Bob Carolyn DavE Ed' NB. Same
$J NB. Shape Of
|.J NB. Reverse
$|.J
;:J NB. Words
$;:J
|.;:J
$|.;:J
>;:J NB. 0pen
$>;:J
|.>;:J
$|.>;:J
<>;:J
$<>;:J
,>;:J
$,>;:J
2#J NB. Copy items of list
$2#J
2#;:J NB. Copy boxes in list
$2#;:J
2#>;:J NB. Copy Items in Columns of Table
$2#>;:J
2#"1 >;:J NB. Copy Items in Rows of Table
$2#"1 >;:J
<'0'
2 6 $<'0' NB. Imagine a box of eggs
3 2 6$<'0' NB. Imagine 3 boxes in a stack
12#'*|V'
3 12$ 12#'*|V'
< 3 12$ 12#'*|V'
4# < 3 12$ 12#'*|V'
= table ~ i.11
]K=:(i.11) = / i.11
GRB viewmat K;'Equal'
]L=:(i.11) < / i.11
GRB viewmat L;'Less Than'
]M=:(i.11) <: / i.11
GRB viewmat M;'Less Or Equal'
]N=:(i.11) ~: / i.11
GRB viewmat N;'Not Equal'
]O=:(i.11) > / i.11
GRB viewmat O;'Larger Than'
]P=:(i.11) >: / i.11
GRB viewmat P;'Larger Or Equal'
]Q=:(i.2) +. / i.2
GRB viewmat Q;'Or'
]R=:(i.2) *. / i.2
GRB viewmat R;'And'
<' '
eb 1
eb 4
eb 2 4
1 boxes 1
1 boxes 4
2 boxes 4
3 boxes 3
,3 boxes 3
S=:i.10
GRB viewmat S
T=:i.100
GRB viewmat T
U=:i.1000000
GRB viewmat U
V=:10 10$i.100
GRB viewmat V
W=:100 100$i.10000
GRB viewmat W
X=:1000 1000$i.1000000
GRB viewmat X
Linda
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of bill lam
Sent: Wednesday, November 12, 2014 12:06 PM
To: Programming forum
Subject: Re: [Jprogramming] greyscale viewmat
The plot looks like the role of rgb to be:
green for luminous
blue for cold / low
red for hot / high.
Does anyone have spare time to waste and post a similar palette for viewmat?
On Nov 12, 2014 4:07 AM, "Jan-Pieter Jacobs" <[email protected]>
wrote:
> It's defined as linear interpolation between a list of RGB values.
> I guess I can't send them without violating any license agreements the
> Uni has, but there's a plot of their values in one of these answers:
>
>
> http://www.mathworks.com/matlabcentral/answers/160332-rgb-values-for-2
> 014b-default-colors
>
> I can imagine it's feasible to construct a similar thing different
> enough to not be plagiarism :)
>
> 2014-11-11 20:28 GMT+01:00 Brian Schott <[email protected]>:
>
> > Jan-Pieter,
> >
> > Yes, that blog does seem to be exactly relevant.
> > Could you tell how the parula palette is defined?
> >
> > On Tue, Nov 11, 2014 at 1:55 PM, Jan-Pieter Jacobs <
> > [email protected]> wrote:
> >
> > > This issue is exactly why Mathworks changed the default color map
> > > in
> > their
> > > 2014b release.
> > > There is an interesting series of blog posts about the motivation
> > > here
> > [0].
> > >
> > > Maybe a similar default colormap would make sense for viewmat too?
> > >
> > > [0]:
> > >
> > >
> >
> http://blogs.mathworks.com/steve/2014/10/13/a-new-colormap-for-matlab-
> part-1-introduction/
> > >
> > > --
> > (B=)
> > --------------------------------------------------------------------
> > -- For information about J forums see
> > http://www.jsoftware.com/forums.htm
> >
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
>
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