Type conversion

You can mix the types of values in your arithmetic expressions. char types will be treated as int. Otherwise where types of different size are involved, the result will usually be of the larger size, so a float and a double would produce a double result. Where integer and real types meet, the result will be a double.

There is usually no trouble in assigning a value to a variable of different type. The value will be preserved as expected except where;

• The variable is too small to hold the value. In this case it will be corrupted (this is bad).
• The variable is an integer type and is being assigned a real value. The value is rounded down. This is often done deliberately by the programmer.

Where a function expects an argument of one type, corruption will occur if the wrong type is supplied. It is possible to use a technique called casting to temporarily disguise the argument as the correct type.

eg. The function sqrt finds the square root of a double.

int i = 256;
int root

root = sqrt( (double) i);