Colorscale at custom location in R

How to create and position a custom color scale in R

just a simple example below

# create a colorramp pallete
pal <- colorRampPalette(c("red", "yellow", "lightgreen","#66FFCC","darkblue","darkblue"))(3300)

# create an empty plot
plot(-1,-1,xlim=c(0,10),ylim=c(0,10),xlab="my x-axis",ylab="my y-axis")

# create new figure on top of old one with different bounds
par(new=T,fig=c(0.6,0.85,0.02,0.77))

# create x, y z values for your image
x=1
z=matrix(1:1500,nrow=1)
y=seq(0,10,len=1500) 

# plot the image
image(x,y,z,col=pal,axes=FALSE,xlab="",ylab="",labels=F)

# enable text outside the drawing area
par(xpd=NA)

# add some text
text(1,11,"(mm)")

# add an axis on the left side
axis(4,las=1,seq(0,10,1),at=seq(0,10,1))

Click here to see the result in Rfiddle.