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Good morning, I'm running into trouble rbind-ing numeric matrices with differing numbers of rows. In particular, there seem to be issues whenever a one-row numeric matrix is involved. Assume A is a numeric matrix with 1 row and Y columns and B is a numeric matrix with X rows and Y columns. Let C be the result of rbinding A and B. Then C is a numeric matrix with X + 1 rows and Y columns, only

I've recently stumbled across data.table, Matthew Dowle's package. I'm impressed by the speed of the package in handling operations with large data.frames, but am a bit overwhelmed with the syntax. I'd like to express the SQL statement below using data.table operations rather than sqldf (which was incredibly slow for a small subset of my financial data) or import/export with a

Hello, I'm having trouble discovering what's going wrong with my use of natural joins via sqldf. Following the instructions under 4i at http://code.google.com/p/sqldf/, which discusses creating indices to speed joins, I have been only unreliably able to get natural joins to work. For example, > Tid <- c('AES 01-01-02 10:58:00', 'AES 01-01-02 11:53:00', 'AES