colortikz-pgf
I have a color hex string, e.g. ecd9ed, I know I can define it as below:
\definecolor{color1bg}{RGB}{236,217,237}
But I wish to skip the conversion from hex to decimal. Is it possible to define a color in hex string? Maybe something like below:
\definecolor{color1bg}{RGB}{#ecd9ed}
The \extractcolorspec macro will define a macro that contains the specification for a color; we can use it and the companion \convertcolorspec to define a macro containing the specifications for another model:
\definecolor{canvascolor}{rgb}{0.643,0.690,0.843}
\extractcolorspec{canvascolor!75!white}{\test}
\expandafter\convertcolorspec\test{HTML}\test
Now \test will expand to BBC4E1.
The first definition of \test will be {rgb}{0.73225,0.7675,0.88225} so this is good for putting it after \convertcolorspec, but we have to expand it first.
Use two different macros if you also need to keep the first specification around.
We can implement this in a function
\newcommand{\getColorSpec}[3][\getColorSpecTemp]{%
\extractcolorspec{#3}\getColorSpecTemp
\expandafter\convertcolorspec\getColorSpecTemp{#2}#1}
With \getColorSpec{HTML}{canvascolor!75!white} the specification will be stored in \getColorSpecTemp; with
\getColorSpec[\HTMLcolor]{HTML}{canvascolor!75!white}
the same specification will be stored in \HTMLcolor.
I basically type too many matrices with lots of figures etc. so it's kind of natural to me to use TikZ for this, but understandably, you might not want to use this. However, there is a particular option in matrix library that you can decide on what to do when a particular entry is empty. Here is an example
\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{matrix}
\begin{document}
I like lower triangular matrices so does Gauss while eliminating.
\[
\begin{tikzpicture}[baseline=(current bounding box.center)]% To center the matrix in the equation
\matrix[matrix of math nodes,execute at empty cell={\node[black!20]{0};},%Node color and text "0"
every left delimiter/.style={xshift=1ex},%tighter delimiter spacing
every right delimiter/.style={xshift=-1ex},
left delimiter={(},right delimiter={)}
] {
1 & & & & & & & & \\
& 1 & & & & & & & \\
& \frac{1}{2} & \frac{1}{2} & & & & & & \\
& & & 1 & & & & & \\
& & & & 1 & & & & \\
& & & & \frac{1}{2} & \frac{1}{2} & & &\\
& & & \frac{1}{2} & & & \frac{1}{2} & & \\
& & & & \frac{1}{2} & & & \frac{1}{2} & \\
& & & & \frac{1}{4} & \frac{1}{4} & & \frac{1}{4} & \frac{1}{4} \\
};
\end{tikzpicture}
\]
\end{document}
Best Answer
\definecolor{color1bg}{HTML}{ECD9ED}is the way to define colors with HTML definition.You need the package
xcolorof course.