code: public static DoubleMatrix log10i(DoubleMatrix x) {
  		/*# mapfct('Math.log10') #*/
  //RJPP-BEGIN------------------------------------------------------------
  	   for (int i = 0; i < x.length; i++)
  	      x.put(i, (double) Math.log10(x.get(i)));
  	   return x;
  //RJPP-END--------------------------------------------------------------
  	}
docs: Applies the <i>logarithm with basis to 10</i> element-wise on this
  matrix. Note that this is an in-place operation.
  @see MatrixFunctions#log10(DoubleMatrix)
  @return this matrix