Function cg = colourgrade_bluered(cg)
cg = colourgrade_bluered(cg,n,reverse)
cg = colourgrade_bluered(cg,[],reverse)
returns struct cg with information
on the colourmap produced by m-file
bluered.m. The colourmap is extended
by three colours (green/gray) to
indicate infra, ultra and na/nan
values.
The colourmap may be practical for
showing negative and positive values.
All input arguments are optional; an
empty matrix [] indicates "no input
for that argument".
If the struct cg contains the fields
cg.gradevalues
cg.tickvalues and/or
cg.ticktexts
and/or
cg.offset
at input, this information will be
used to produce the colourmap. However,
if input argument n is provided, the
first three fields will be (re)defined
based on the number of grades n.
If neither information from cg at input
can be obtained, nor input argument n
is given, defaults will be set for the
above mentioned fields.
At input, the struct cg may have the following
optional fields:
cg.gradevalues (column vector of reals)
cg.gradeticks (column vector of booleans)
cg.gradetexts (column cell-array of strings)
cg.offset (cg.icm_min + cg.offset is the
row index to the colourmap
where the second part starts)
At output, the struc cg contains new or renewed fields:
cg.offset (cg.icm_min + cg.offset is the
row index to the colourmap
where the second part starts)
cg.colourmap (colourmap, a n*3 matrix)
cg.icm_infra (row index to cg.colourmap)
cg.icm_min (row index to cg.colourmap)
cg.icm_max (row index to cg.colourmap)
cg.icm_ultra (row index to cg.colourmap)
cg.icm_nanan (row index to cg.colourmap)
The output struc cg contains also any
other fields with defaults defined by
m-file colourgrade_init.m.
The function internally calls the following
non-standard m-files:
bluered.m
colourgrade_init.m
colourgrade_init_ngrade.m
(c) 2026 fabien van mook
2026.08.20 release of this file within package "fvm-colourgrade" under GNU GPLv3+
