Texas Instruments TINSPIRE Reference Guide - Page 73

nDerivative( ) nDerivative(Expr1,Var=Value[,Order]) ⇒ value nDerivative(Expr1,Var[,Order]) | Var=Value ⇒ value Returns the numerical derivative calculated using auto differentiation methods. When Value is specified, it overrides any prior variable assignment or any current "with" substitution for the variable. If the variable Var does not contain a numeric value, you must provide Value. Order of the derivative must be 1 or 2. Note: The nDerivative() algorithm has a limitiation: it works recursively through the unsimplified expression, computing the numeric value of the first derivative (and second, if applicable) and the evaluation of each subexpression, which may lead to an unexpected result. Consider the example on the right. The first derivative of x·(x^2+x)^(1/3) at x=0 is equal to 0. However, because the first derivative of the subexpression (x^2+x)^(1/3) is undefined at x=0, and this value is used to calculate the derivative of the total expression, nDerivative() reports the result as undefined and displays a warning message. If you encounter this limitation, verify the solution graphically. You can also try using centralDiff(). newList( ) newList(numElements) ⇒ list Returns a list with a dimension of numElements. Each element is zero. newMat( ) newMat(numRows, numColumns) ⇒ matrix Returns a matrix of zeros with the dimension numRows by numColumns. nfMax( ) nfMax(Expr, Var) ⇒ value nfMax(Expr, Var, lowBound) ⇒ value nfMax(Expr, Var, lowBound, upBound) ⇒ value nfMax(Expr, Var) | lowBound Catalog > Catalog > TI-Nspire™ Reference Guide 67