Adding an additional variable (Derivative(expr, name, name2)) takes the second derivative.
Floor( 2.7 );
Floor( –.5 );
expr an expression that defines the integrand.
varname the name of the variable of integration. If this variable contains a value, that value specifies a starting value that is used as a typical value to improve the accuracy of the integral.
lowLimit specifies the lower limit of integration. To specify negative infinity as the lower limit of integration, set this to missing.
upLimit specifies the upper limit of integration. To specify positive infinity as the upper limit of integration, set this to missing.
StoreInfo saves diagnostics of the numerical integration routine to the argument of StoreInfo().
StartingValue specifies a starting value that is used as a typical value to improve the accuracy of the integral.
Returns the numerical derivative of the f( x,... ) function with respect to one of its arguments. You can specify that argument as the second argument in the Num Deriv function. If no second argument is specified, the derivative is taken with respect to the function's first argument. The derivative is evaluated using numeric values specified in the f( x,... ) function expression.
The Num Deriv() function might appear not to produce the correct results as seen here:
x = 3;
Returns the numerical second derivative of the f( x,... ) function with respect to x. The derivative is evaluated using numeric values specified in the f( x,... ) function expression.