Write a function that divides two numbers. If the divider is zero, it shouldn’t try the division, but give a message about it.
Write a function that changes all vowels of a string to e-s.
Add a checking part, that checks if the input is indeed one character and it has vowels in it. If not, it should give a message.
Write a function that calculates the variance of a vector.
\[Var(x)=\frac 1{n-1}\sum_{i=1}^{n} (x_{i}-\overline{x})^2\] where \[\overline{x}=\frac{\sum_{i=1}^{n}x_{i}}n\]
Add code to check if the input data is in the correct format.
Add a warning, if the class of the input vector is not numeric, and try to coerce as one.