library(tidyverse)

set.seed(1)
mydata = data.frame(x = runif(20),
                     y = runif(20))
mydata = mydata %>%
    mutate(x = round(x, 2)) %>%
    mutate(y = round(y, 2)) %>%
    mutate(color = round(x - y,2)) %>%
    mutate(shape = gl(3,20/3))
#write_csv(mydata, 'color-and-shape.csv')

ggplot(mydata, aes(x = x, y = y, color = color, shape = shape)) +
    geom_point(size = 5)
ggsave('color-and-shape.png', width = 7, height = 5)

documentclass[margin=2pt]{standalone}

usepackage{filecontents}
begin{filecontents*}{color-and-shape.csv}
x,y,color,shape
0.27,0.93,-0.66,1
0.37,0.21,0.16,1
0.57,0.65,-0.08,1
0.91,0.13,0.78,1
0.2,0.27,-0.07,1
0.9,0.39,0.51,1
0.94,0.01,0.93,2
0.66,0.38,0.28,2
0.63,0.87,-0.24,2
0.06,0.34,-0.28,2
0.21,0.48,-0.27,2
0.18,0.6,-0.42,2
0.69,0.49,0.2,3
0.38,0.19,0.19,3
0.77,0.83,-0.06,3
0.5,0.67,-0.17,3
0.72,0.79,-0.07,3
0.99,0.11,0.88,3
0.38,0.72,-0.34,1
0.78,0.41,0.37,1
end{filecontents*}

usepackage{pgfplots}
pgfplotsset{width=7cm,compat=newest}

begin{document}
begin{tikzpicture}
begin{axis}[colorbar horizontal]
    addplot[scatter,only marks,point meta=explicit] table
        [x=x,y=y,meta=color,col sep=comma] {color-and-shape.csv};
end{axis}
end{tikzpicture}
end{document}