r - Highlight tiles with ggplot2 geom_tile() + geom_point() -

i have following plot looks like:

i'm trying add points in layer using according following code found here

my data frame i'm importing looks this:

residue_id  residue_num per_ddg pg9_seq_bool   96  0.00437094862845686 false   97  -0.0026333752377897 false   98  -0.00453070737795937    false   99  -0.0130564560942629 true   100 -0.00578979380922636    false   101 -0.0128130535970934 false   102 -0.0264740211311766 false   103 -0.183036342874782  false   104 -0.00550669729238368    false 

and uses following code generate plot:

library(ggplot2) input_ddg <-read.table('per_residue_average.txt',header=t,sep="\t",stringsasfactors=true) input_ddg$pg9_seq_bool[input_ddg$pg9_seq == "true"] <- t input_ddg$pg9_seq_bool[input_ddg$pg9_seq == "false"] <- f   pdf("output.pdf")                                                                                                                                                       ggplot(input_ddg, aes(residue_id,residue_num,fill=per_ddg) ) +                               theme_bw() +                                                                   geom_tile() +                     geom_point(data=input_ddg,aes(size=ifelse(pg9_seq_bool, "dot", "no_dot"))) +   scale_size_manual(values=c(dot=6,no_dot=na))+                                                                    scale_fill_gradient2(low="blue", mid="white",high="red", midpoint=-.25, na.value="black") +        ylab( "residue number" ) +                                                     xlab( "mutation identity")    +        scale_y_continuous(breaks=96:125,expand=c(0,0))+   scale_x_discrete(expand=c(0,0))+   labs(fill=expression(delta*delta*"g(reu)")) +   ggtitle(expression("average"~delta*delta*"g mutations cdr3 position")) +   theme(  panel.background=element_rect(fill="black"), panel.grid.minor=element_blank(), panel.grid.major=element_blank()) dev.off() 

i'm getting error:

error in grid.call.graphics(l_setviewport, pvp, true) :  non-finite location and/or size viewport calls: print ... lapply -> fun -> push.vp.viewport -> grid.call.graphics in addition: warning message: removed 461 rows containing missing values (geom_point).  execution halted 

i have feeling due parsing of true , false ifelse, followed post exactly.

first, don't need replace true , false values t , f in data fram input_ddg. next, column pg9_seq_bool can used directly in aes() of geom_point(). produce 2 types of points according true/false values. scale_size_manual() set size 0 false , 6 true. if point size shouldn't appear in legend add argument guide="none" in scale_size_maual().

ggplot(input_ddg, aes(residue_id,residue_num,fill=per_ddg) ) +                               theme_bw() +                                                                   geom_tile() +                     geom_point(aes(size=pg9_seq_bool)) +   scale_size_manual(values=c(0,6),guide="none")