Color palette converter utility Pc#

Because I put the COLOR variable on the ID statement, each marker is labeled by using its hexadecimal value: The PRINCOMP procedure creates a graph that projects each RGB value onto the principal component axes. You could add a third principal component if you want to have a way to separate the green and blue colors. Along the axis of the second PC, colors that have a lot of green and blue (such as cyan, which is (0, 255, 255)) have extreme negative values whereas colors that are mostly red have extreme positive values.Īn additional table (not shown) indicates that 89% of the variation in the data is explained by using the first two principal components.

Color palette converter utility Pc#

The second PC is a contrast between the red coordinate and the green and blue coordinates. The second principal component is the linear combination Similarly, white is on the extreme right since white has the RGB value (255, 255, 255). Along the axis of the first PC, black is on the extreme left since black has the RGB value (0, 0, 0). More weight is given to the green and blue components than to the red component. The first PC is a weighted sum of the amount of color across all three variables. The table shows that the first principal component (PC) is the linear combination

Recall that each principal component is a linear combination of the original variables (R, G, and B). Proc princomp data=RGB N= 2 out=PCOut plots (only )= (Score Pattern ) Let's use PROC PRINCOMP in SAS to run a principal component analysis of these 41 observations: Thus, the data contains 41 triplets of RGB values. The R, G, and B variables contain the red, green, and blue components, respectively, which are in the range 0 to 255. The result of this DATA step is a data set that contains 41 rows. Holiday Red and Gold 6 CXCF1931 CXAD132D CXD9991A CXEAA61E CXF2BC13 CX216A1B * Palette Name |n| color1 | color2 | color2 | color4 |. ID + 1 /* assign a unique ID to each color */ end Ĭall symput ( 'AllColors', palette ) /* concatenate colors store in macro */ drop n col palette Input color = inputn ( substr (color, 3, 2 ), 'HEX2.' ) /* get RGB colors from hex */ Length palette $450 /* must be big enough to hold all colors */ retain ID 1 palette As explained in the previous article, the DATA step also creates an ID value for each color and creates a macro variable (AllColors) that contains the list of all colors. informat to convert the hexadecimal values to their equivalent RGB values. The following DATA step reads the colors in the Christmas palettes and uses the HEX2. The colors in SAS are 8-bit colors, which means that each coordinate in RGB space has a value between 0 and 255. I thought it would be fun to use principal component analysis to compute and visualize the linear subspace that best captures the set of Christmas colors!Įach color can be represented as an ordered triplet of unsigned integers in RGB space. Rather, they represent a specific subset of Christmas colors. Clearly, the colors in the Christmas palettes are not a random sample from the space of RGB colors. You can see that the palettes include many red, green, and golden colors. In a previous article, I visualized seven Christmas-themed palettes of colors, as shown to the right.