ComplexHeatmap break values appear different in the plots

Question

[EagleEye]

Hi,

I am using ComplexHeatmap package for plotting. One strange thing I noticed is that, heatmap does not take maximum and minimum break values as specified using max and min functions from R.

Code/commands used:

> min(xm)
[1] -5.460918
> max(xm)
[1] 9.361317

> Heatmap( xm, col = colorRamp2(c(min(xm), 0, max(xm)), c("#6E6E6E", "white", "#31B404")), show_row_names = F, km = 2, column_names_gp = gpar(fontsize = 7), name="Tumors" )

Please let me know if I am doing something wrong.

My session information:

> sessionInfo()
R version 3.5.0 (2018-04-23)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: CentOS Linux 7 (Core)

Matrix products: default
BLAS: /sw/apps/R/x86_64/3.5.0/rackham/lib64/R/lib/libRblas.so
LAPACK: /sw/apps/R/x86_64/3.5.0/rackham/lib64/R/lib/libRlapack.so

locale:
 [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C
 [3] LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8
 [5] LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8
 [7] LC_PAPER=en_US.UTF-8       LC_NAME=C
 [9] LC_ADDRESS=C               LC_TELEPHONE=C
[11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C

attached base packages:
[1] grid      stats     graphics  grDevices utils     datasets  methods
[8] base

other attached packages:
[1] circlize_0.4.6        pheatmap_1.0.12       RColorBrewer_1.1-2
[4] gridExtra_2.3         ggplot2_3.2.1         ComplexHeatmap_1.20.0
[7] reshape2_1.4.3        svMisc_1.1.0

loaded via a namespace (and not attached):
 [1] Rcpp_1.0.2          magrittr_1.5        tidyselect_0.2.5
 [4] munsell_0.5.0       colorspace_1.4-1    R6_2.4.0
 [7] rjson_0.2.20        rlang_0.4.0         stringr_1.4.0
[10] plyr_1.8.4          dplyr_0.8.3         tools_3.5.0
[13] gtable_0.3.0        withr_2.1.2         assertthat_0.2.1
[16] lazyeval_0.2.2      tibble_2.1.3        crayon_1.3.4
[19] purrr_0.3.2         GlobalOptions_0.1.0 glue_1.3.1
[22] shape_1.4.4         stringi_1.4.3       compiler_3.5.0
[25] pillar_1.4.2        scales_1.0.0        pkgconfig_2.0.2
[28] GetoptLong_0.1.7

Note: Also posted this on GitHub.

[russhh]

Could you save your heatmap in an object and print the contents of my_heatmap@matrix_color_mapping, please

[EagleEye]

Sorry, I am not able to understand your suggestion. Can you please explain ?

[ATpoint]

He means:

my_heatmap <- Heatmap( xm, col = colorRamp2(c(min(xm), 0, max(xm)), c("#6E6E6E", "white", "#31B404")), show_row_names = F, km = 2, column_names_gp = gpar(fontsize = 7), name="Tumors" )

## and then show output of:
my_heatmap@matrix_color_mapping

[ATpoint]

See also https://github.com/jokergoo/ComplexHeatmap/issues/82 for the developers answer on this. At the bottom of this issue he has some suggestions on how to avoid the default breaks. Using quantile on your matrix allows setting data-driven cutoffs for the range. See the issue for details.

[EagleEye]

Dear ATpoint, thanks a lot for your suggestion. My problem is exactly opposite to the issue mentioned in the link you provided. I am not using default breaks, providing the breaks using min and max function. Above heatmap I provided is having symmetric legend scale, but my data does not have min and max values as symmetric. I do not want to spread the gradient up-to '-10' when the data/matrix has the minimum value of '-5.460918'. Instead I would like to stop the gradient fill at exact minimum (not possible) or atleast -6 (round-off).

I have been communicating with the developer. Here is the link for reported issue, https://github.com/jokergoo/ComplexHeatmap/issues/361

[EagleEye]

Heatmap function doesn't recognize the break values I mentioned using min and max.

> ht <- Heatmap( xm, col = colorRamp2(c(min(xm), 0, max(xm)), c("#6E6E6E", "white", "#31B404")), show_row_names = F, km = 2, column_names_gp = gpar(fontsize = 7), name="Tumors" )

> ht@matrix_color_mapping
Continuous color mapping:
name: Tumors
default breaks:
[1] -10  -5   0   5  10

colors:
[1] "#6E6E6EFF" "#797979FF" "#FFFFFFFF" "#A3DA8BFF" "#31B404FF"