#273 Problems with division by zero in function plot

[Fellype]

If you try to create a function plot that contains a division by zero at some point of the curve, SciDAVis begins to show a high consumption of CPU and memory and it affects all the operating system.

Steps to reproduce the bug:
1) Open the "Add function curve" dialog in File -> New -> New Function Plot
2) Enter a function like "1/x"
3) Select the x range starting (or ending) with zero
4) Click Ok -> the memory and CPU usage will start to increase and the system will be slow

Tested with v. 1.D8 on Linux and 1.D9 Windows version on Linux+wine.

There are no detected problems with division by zero in tables, graphics and/or scripts (SciDAVis returns "inf" in these cases).

[narunlifescience]

when ever there is a divide by zero, scidavis seems to be throwing 4 unhandled exceptions:

(std::bad_alloc sending event 12 QResizeEvent to object graph 5 Graph) x 2times
std::bad_alloc sending event 11 QMouseEvent to object 11 QPushButton
std::bad_alloc sending event 12 QEventto object 4 Plot

should nt be hard to fix i guess..