frudawski

plottregenza

The plottregenza function creates a 2D illustration of the Tregenza sky hemisphere.

See also: plotskydirecto

Usage:

plottregenza(values,clr,clabel,info,fontsize,sun)

Where:

ParameterDescription
valuesContains the to be plotted data as 145\times1 vector or 145\times2 matrix. The first column sets the patch data, the second is for additional false-colours illustration, e.g. luminance and CCT in one illustration.
clr
(optional)
Specifies the patch colours:
145\times3 matrix to specify each patch colour.
1\times3 vector to specify an uniform patch colour.
‘w’ for white
‘gray’ for grayscales with colourbar (default)
‘clr’ for false-colours with colourbar
clabel
(optional)
Specifies the colourbar label. The colourbar is only visible if two datasets are given.
info
(optional)
Is a cell array that prints additional information, up to 20 elements. Elements can be empty or incomplete.
fontsize
(optional)
Specifies the fontsize of the values, numeric, default 8.
sun
(optional)
Specifies the sun position, 1\times2 vector [azimuth elevation].

Examples

Plot CIE sky 12 at \alpha = 192° and \gamma = 42° with resulting horizontal illuminance of E_h = 50000~\textrm{lx}:

L = ciesky(12,192,42,'Eh',50000);
plottregenza(L)

See also: ciesky

Result:

Plot Tregenza patch numbers with white patches:

plottregenza(1:145,'w')

Result:

Plot CIE sky 12 at \alpha = 192° and \gamma = 42° with resulting horizontal illuminance of E_h = 50000~\textrm{lx} in false-colours:

L = ciesky(12,192,42,'Eh',50000);
plottregenza(L,'clr')

See also: ciesky

Result:

Plot CIE sky 7 at \alpha = 95° and \gamma = 12° with resulting horizontal illuminance of E_h = 50000~\textrm{lx} with patchnumbers in false-colours:

n = 1:145;
L = ciesky(7,95,12,'Eh',50000);
plottregenza([n' L],'gray','L in cd m^{-2}')

See also: ciesky

Result:

Plot CIE sky 12 at \alpha = 210° and \gamma = 34° with resulting horizontal illuminance of E_h = 100\,000~\textrm{lx} with sun position and info labels:

t = {'CIE sky 12','\alpha_S = 210','\gamma_S = 34','E_h = 50 klx','L',...
     'field 06','field 07','field 08','field 09','field 10',...
     'field 11','field 12','field 13','field 14','field 15',...
     'field 16','field 17','field 18','field 19','field 20'};
L = ciesky(12,210,34,'Eh',100000);
plottregenza(L,'gray',[],t,8,[210 34])

See also: ciesky

Result:

Reference:

Peter Roy Tregenza: Subdivision of the sky hemisphere for luminance measurements. In: Lighting Research and Technology, vol. 19, no. 1, pp. 13-14, 1987, (DOI: 10.1177/096032718701900103).

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