Page 231 - Compact Numerical Methods For Computers
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                                         TABLE  18.1. Derivative approximations computed by formula (18.4) on a Data General NOVA. (Extended BASIC  system. Machine precision = 16 .)
                                                               log(b)                                 exp(b)                                     tan(b)

                                            h      b = 0·001   b = 1     b = 100      b = –10    b = 0·001  b = l   b = 100      b = 0   b = l     b = l·57   b = –1.57

                                      1            6·90876   0·693147  0·95064E–3   7·80101E–5  1·72      4·67077  4·6188E43   1·55741  –3·74245  –1256·61   1255·32
                                      0·0625       66·4166   0·969993  9·99451E–3  4·68483E–5   1·03294   2·80502  2·7737H343  1·0013   3·80045  –20354·4    19843
                                      3·90625E–3   407·171   0·998032  1·00098E–2  4·54858E–5   1·00293   2·72363  2·69068E43  1        3·44702  –403844     267094
                                      2·44141E–4   894·754   0·999756  1·17188E–2  4·52995E–5   1         2·71875  2·67435E43  0·999999  3·42578  2·2655E6   1·2074E6
                                      1·52588E–5   992·437   1         0·0625      4·3869E–5    1         2·75    1·81193E43   0·999999 3·5       1·57835E6  1·59459E6
                                      9·53674E–7   1000      1        0             3·05176E–5  1         2       0            0·999999† 5        1·24006E6  2·47322E6
                                      1·93024E–6   999·012†                                     0·988142†
                                      9·77516E–4             0·999512†                                    2·72†                         3·43317†
                                      9·76572E–2                      9·9999E–3†                                  2·82359E43†
                                      9·76658E–3                                   4·56229E–5†
                                      1·53416E–3                                                                                                 –1·70216E6† 539026†
                                      Analytic
                                      derivative‡  1000      1        0·01         4·54E–5      1.001     2.71828 2·68805E43 1          3.42552   1·57744E6  1·57744E6

                                      † h computed by formula (18.5).
                                      ‡ The analytic derivative reported has been evaluated on the NOVA system and maybe in error to the extent that the special function routines of this system
                                      are faulty.
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