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B.1.2 Maths

Standard mathematical and trigonometric functions.

E
Euler's number e, the base of natural logarithms.
PI
Pi, the ratio of the circumference of a circle to its diameter.
RANDOM
Evaluates to a random number in the range 0<=x<1. This is different for each cell of the table. The quality of the randomness may not be particularly good.
sin( theta )
Sine of an angle.
cos( theta )
Cosine of an angle.
tan( theta )
Tangent of an angle.
asin( x )
Arc sine of an angle. The result is in the range of -pi/2 through pi/2.
acos( x )
Arc cosine of an angle. The result is in the range of 0.0 through pi.
atan( x )
Arc tangent of an angle. The result is in the range of -pi/2 through pi/2.
exp( x )
Euler's number e raised to a power.
log10( x )
Logarithm to base 10.
ln( x )
Natural logarithm.
sqrt( x )
Square root. The result is correctly rounded and positive.
atan2( y, x )
Converts rectangular coordinates (x,y) to polar (r,theta). This method computes the phase theta by computing an arc tangent of y/x in the range of -pi to pi.
pow( a, b )
Exponentiation. The result is the value of the first argument raised to the power of the second argument.
sinh( x )
Hyperbolic sine.
cosh( x )
Hyperbolic cosine.
tanh( x )
Hyperbolic tangent.
asinh( x )
Inverse hyperbolic sine.
acosh( x )
Inverse hyperbolic cosine.
atanh( x )
Inverse hyperbolic tangent.


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TOPCAT - Tool for OPerations on Catalogues And Tables
Starlink User Note253
TOPCAT web page: http://www.starlink.ac.uk/topcat/
Author email: m.b.taylor@bristol.ac.uk
Mailing list: topcat-user@bristol.ac.uk