Adrian questions

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• R: using factor variables in nlme function
• R: where is the gradient step in the xgboost source code?
• R: using dplyr to remove certain rows in the data.frame
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• R: how to move axes labels closer to the plot
• How to stop a command in R in Windows
• R: changing color of stacked barplot
• R: regular expression to specify end of string char is a letter

Adrian answers