# [R] Problem with colors in contour plot

Loukia Spineli spineliloukia26 at gmail.com
Thu Oct 4 15:18:39 CEST 2012

```The contpour plot is very impressive!!! The contour plot I want to display
should have only 2 colors: white a grey. I have created this plot for only
one trial (see, ppts) and now I am attempting to do the same for many
trials.

On Thu, Oct 4, 2012 at 3:51 PM, Rui Barradas <ruipbarradas at sapo.pt> wrote:

>  Hello,
>
> Something like this?
>
>
> myRamp <- colorRampPalette(c("lightblue", "darkblue"))
> mypal <- myRamp(20)
> mypal[1] <- rgb(1, 1, 1)
>
> #?filled.contour
> ## Persian Rug Art:
> x <- y <- seq(-4*pi, 4*pi, len = 27)
> r <- sqrt(outer(x^2, y^2, "+"))
> filled.contour(cos(r^2)^2, frame.plot = FALSE,
>                plot.axes = {}, col = mypal)
> grid()
>
>
> Hope this helps,
>
> Em 04-10-2012 13:25, Loukia Spineli escreveu:
>
> Dear R users,
>
> I have a 51 by 51 matrix of p-values (named as pvalue_MA). I want to
> present graphically this matrix in a plot (filled contour plot) where both
> axes represent probabilities. I have also added a grid in this plot. I want
> to highlight in white the cells of the grid that represent p-values smaller
> than the (common) significance threshold, 0.05. The code from this plot is
> colored in blue (I had to copy-pasted all this code in order to reach to
> the plot). I suspect that the "problem" might be in the col parameter of
> the filled.contour function. Honestly, I cannot understand why the plot
> appears to be completely white!! I checked the values of my variable and it
> has a great range from 0 to 1.
> Any suggestion/ comment would really help me to move on with my project.
>
> All the best,
>
> Loukia
>
>
>
> ______________________________________________R-help at r-project.org mailing listhttps://stat.ethz.ch/mailman/listinfo/r-help
> and provide commented, minimal, self-contained, reproducible code.
>
>
>
```