Hi 

I am trying to create heatmaps. I have used heatmap.2, pheatmap and clustvis. I have dataset of 2000 rows containing allele frquency of different SNPs in different populations. I cannot filter rows as I am visualizing relationship between different populations on the basis of allele frequencies. The problems with R packages is that they does not create good resolution heatmaps. And clustvis plots heatmaps on the basis of principal components not on the basis of actual allele freqiencies.

Can anyone please tell me how to great good resolution heatmaps of such large datasets?  
 
The resolution or overall sense of 'quality' of a figure is determined by a few different factors, including (but not limited to):

 - your monitor's type and capabilities (LED, etc)
 - the screen resolution you have set via your operating system
 - the compression format (or not) in which you're encoding your figure
   (PNG, TIFF, PDF, etc)
 - how much information you are attempting to 'pack' into the figure

Problems with heatmaps in R are usually related to too much information being 'packed' into too small a space.

The first thing that you should do is save your figure in a vector-based format, such as PDF, and then you can manage the 'packing' of information into this by altering the width and height, for example:

    pdf("Test.pdf", width=7, height=7)
    ...
    dev.off()

Increase size:

    pdf("Test.pdf", width=12, height=18)
    ...
    dev.off()

`width` and `height` here relate to inches.

With other formats, like TIFF, PNG, *et cetera*, width and height relate to pixels, but the resolution will never have the clarity as in vector-based formats.

Kevin