plotting functions but not for return values outside specified range

[Fortin]

Sometimes using "" for the undefined value has caused me to have 'unexpected results'. I prefer to use 0/0 or to just remove the default in the piecewise template by using backspace on the last filled square. (a comma at the end of the line will bring the next line back)

Either solution works well, but I think that the one line piecewise template is easier to read.

{R1(Theta) if R1(Theta)>-30