1. CPSC 110 - Pascal Brent M. Dingle Texas A&M University Chapter 3
Finishing Chapter 3
CPSC Pascal Brent M. Dingle Texas A&M University
Chapter 3

2. Predefined Functions
Pascal, like most programming languages, offers a set of predefined functions.
Unfortunately not all languages offer the same set of predefined functions.
Some functions Pascal offers are:
sqrt(x); - returns the square root of x
abs(x); - returns the absolute value of x
round(x) - rounds x to the nearest integer
trunc(x) - truncates x to the nearest integer
sqr(x) - returns x squared (i.e. x*x)

3. Natural Logarithm and e
Pascal also offers the predefined functions:
ln(x)
exp(z)
ln(x) returns the natural log of x. aside: natural log is log base e where e is approximately
exp(z) returns e raised to the z power

4. ln and exp trick Suppose you wanted to set z = xy.
We know xy = (eln(x))y = ey*(ln(x)).
And ey*(ln(x)) = exp(y*ln(x)).
So to set z = xy, we would say: z := exp( y * ln(x) );

5. End Predefines and ln and e