Constants and variables

E : Euler's number e, base of the natural logarithms.
PI : pi, the ratio of the circumference of a circle to its diameter.
L : this special variable holds the line number.
C1,C2... : these special variables hold the values in your cells: C1 for column 1, etc.

Pitfalls

Multiplication mandates the use of the '*' symbol
Do not omit the '*' for multiplication, especially before the 'L' variable: 5C1 is invalid, and 5L is valid but means '5', it does not mean '5*L'.

Powers: use the pow(x,y) function
Do not use the '^' sign which is the bitwise XOR operator.

Mathematical functions

abs(x)
      Returns the absolute value of x.
acos(x)
      Returns the arc cosine of a value; the returned angle is in the range 0.0 through pi.
asin(x)
      Returns the arc sine of a value; the returned angle is in the range -pi/2 through pi/2.
atan(x)
      Returns the arc tangent of a value; the returned angle is in the range -pi/2 through pi/2.
atan2(y,x)
      Returns the angle theta from the conversion of rectangular coordinates (x, y) to polar coordinates (r, theta).
cbrt(x)
      Returns the cube root of a value.
ceil(x)
      Returns the smallest (closest to negative infinity) integer that is greater than or equal to the argument.
cos(x)
      Returns the trigonometric cosine of an angle.
cosh(x)
      Returns the hyperbolic cosine of a value.
exp(x)
      Returns Euler's number e raised to the power of a value.
expm1(x)
      Returns exp(x) -1.
floor(x)
      Returns the largest (closest to positive infinity) integer that is less than or equal to the argument.
fp(x)
      Converts x to a floating-point value.
hypot(x,y)
      Returns sqrt(x^2 +y^2) without intermediate overflow or underflow.
log(x)
      Returns the natural logarithm (base e) of a value.
log10(x)
      Returns the base 10 logarithm of a value.
log1p(x)
      Returns the natural logarithm of the sum of the argument and 1.
max(x, y)
      Returns the greater of two values.
max(float a, float b)
      Returns the greater of two float values.
max(int a, int b)
      Returns the greater of two int values.
max(long a, long b)
      Returns the greater of two long values.
min(x, y)
      Returns the smaller of two values.
pow(x, y)
      Returns the value of the first argument raised to the power of the second argument.
random()
      Returns a value with a positive sign, greater than or equal to 0.0 and less than 1.0.
rint(x)
      Returns the integer that is closest in value to the argument.
round(x)
      Returns the closest long integer to the argument.
signum(x)
      Returns the signum function of the argument; zero if the argument is zero, 1.0 if the argument is greater than zero, -1.0 if the argument is less than zero.
sin(x)
      Returns the trigonometric sine of an angle.
sinh(x)
      Returns the hyperbolic sine of a value.
sqrt(x)
      Returns the correctly rounded positive square root of a value.
tan(x)
      Returns the trigonometric tangent of an angle.
tanh(x)
      Returns the hyperbolic tangent of a value.
toDegrees(xgrad)
      Converts an angle measured in radians to an approximately equivalent angle measured in degrees.
toRadians(xdeg)
      Converts an angle measured in degrees to an approximately equivalent angle measured in radians.

Advanced usage and precision considerations

Before the computation, each parameter (C1,C2...) is converted to a double-precision floating-point value.
This means, if C1 and C2 are integers, then C1/C2 yields a double-precision floating-point result: the quotient is not truncated like it would be without this conversion to floating-point. Also, precision loss may occur with huge long integers (above 10^15). As far as we know, seismic processing uses far more floating-point data than huge integers (if any), so it should not be a problem. If it is for you, please let us know!

Should you really need integer division (or any other reason not to have your variables converted to floating-point), you can use the hash sign just before the variable name: '#C1' instead of 'C1'. This way, C1 will be computed with no conversion, and you will not loose precision in your long integers.

If the result is of floating-point nature, and is to be stored in an integer column, then it is rounded (not truncated).