A Simple Automatic Derivative Evaluation Program A procedure for automatic evaluation of total/partial derivatives of arbitrary algebraic functions is presented. The technique permits computation of numerical values of derivatives without developing analytical expressions for the derivatives. The key to the method is the decomposition of the given function, by introduction of intermediate variables, into a series of elementary functional steps. A library of elementary function subroutines is provided for the automatic evaluation and differentiation of these new variables. The final step in this process produces the desired function's derivative. The main feature of this approach is its simplicity. It can be used as a quick-reaction tool where the derivation of analytical derivatives is laborious and also as a debugging tool for programs which contain derivatives. CACM August, 1964 Wengert, R. E. CA640801 JB March 9, 1978 7:38 PM 1028 5 1029 1029 5 1029 1029 5 1029 1029 5 1029 1216 5 1029 1278 5 1029 1347 5 1029 1396 5 1029 1536 5 1029 964 6 1029 973 6 1029 1028 6 1029 1028 6 1029 1028 6 1029 1028 6 1029 1029 6 1029 1029 6 1029 1029 6 1029 1029 6 1029 1029 6 1029 1029 6 1029 1083 6 1029 1132 6 1029 1214 6 1029 1278 6 1029 1278 6 1029 1334 6 1029 1365 6 1029 1386 6 1029 1387 6 1029 1388 6 1029 1392 6 1029 1393 6 1029 1394 6 1029 1395 6 1029 1396 6 1029 1397 6 1029 1496 6 1029 284 6 1029 407 6 1029 3199 6 1029 3200 6 1029 3201 6 1029 3202 6 1029 3203 6 1029 3204 6 1029 561 6 1029 561 6 1029 561 6 1029 730 6 1029