I have a dataframe:

```
>picard
count    reads
 1    20681318
 2     3206677
 3      674351
 4      319173
 5      139411
 6      117706

```

How do I plot log10(count) vs log10(reads) on a ggplot (barplot)?

I tried: 

```
ggplot(picard) + geom_bar(aes(x=log10(count),y=log10(reads)))

```

But it is not accepting y=log10(reads). How do I plot my y values?