change y axis label for histogram plot

[Tom Song]

Hi,
I want to change the y axis title from default "count" to
"frequency" with the following command;

qplot(carat, data = diamonds, geom = "histogram",ylab='frequency')

but it doesn't work. It still shows count as the label for y axis.
Any suggestions of how to change the default label?

Thanks for help!

Regards,

Tom

[Juliet Hannah]

qplot(carat, data = diamonds, geom = "histogram") +
scale_y_continuous("Frequency")