Fixed cumulative frequency and cumulative percentage problem reported to the commons-dev list by Jon Langlois on 9/14. Integer arguments to getCumXxx were always returning 0 due to type conversion problems. Fixed locale-dependency in ComplexFormat. Renamed univariate package to descriptive and multivariate to regression. Improved efficiency of logGamma method in o.a.c.m.special.Gamma Added subMatrix and matrix-valued row and column accessor methods to RealMatrix interface and RealMatrixImpl. Implemented equals and hashCode in RealMatrixImpl. Fixed RealMatrixImpl toString method to handle empty matrix. Added support for "population" variance and standard deviation in Variance (resp. StandardDeviation) classes. Removed data mutators from RealMatrix interface and RealMatrixImpl. RealMatrix instances are now immutable. Added MatrixUtils class, including static factory methods to create matrices from double[] or double[][] arrays. Changed factorial methods to return 1 for argument = 0, instead of (incorrectly) throwing IllegalArgumentException. Fixed error in SimpleRegression.getSignificance. Value returned was off by a factor of 2 (did not match javadoc). This is the first release of Commons Math. Commons Math is a library of lightweight, self-contained mathematics and statistics components. The release candidate is being made available so that users can test the release and provide feedback.