Automatic setting of breaks with probit scale

[krlmlr]

Automatic setting of breaks fails with probit scale if there are values
too close to 0 or 1.

Bug

qplot(c(0.25, 8), c(0.03, 0.95)) + scale_y_continuous(trans = "probit")

## Error: 'from' cannot be NA, NaN or infinite

Data-dependent: y values further away from 0 or 1 don't trigger it

qplot(c(0.25, 8), c(0.3, 0.7)) + scale_y_continuous(trans = "probit")

Workaround: Set explicit breaks

qplot(c(0.25, 8), c(0.03, 0.95), data = soilSample) + scale_y_continuous(trans = "probit", 
    breaks = seq(0.2, 0.8, 0.2))

Bug with explicit breaks

qplot(c(0.25, 8), c(0.03, 0.95)) + scale_y_continuous(trans = "probit", 
    breaks = seq(0, 1, 0.2))

## Error: 'from' cannot be NA, NaN or infinite

See also daqana/tikzDevice@9f381e6

[hadley]

This sounds like a great feature/horrible bug, but unfortunately we don't currently have the development bandwidth to support it/fix it. If you'd like to submit a pull request that implements this feature/fixes this bug, please follow the instructions in the development vignette.