POISSON: C++ version A program for solving the Poisson equation. The number of interior X grid lines is 9 The number of interior Y grid lines is 9 INIT_SERIAL: Max norm of exact solution U at interior nodes = 0.724287 INIT_SERIAL: Max norm of boundary values = 0.841471 INIT_SERIAL: Max norm of right hand side F at interior nodes = 1.17335 The X grid spacing is 0.1 The Y grid spacing is 0.1 Step ||U|| ||Unew|| ||Unew-U|| ||Unew-Exact|| 1 0.403397 0.497847 0.144939 0.4921 2 0.570316 0.604994 0.0631442 0.401573 3 0.634317 0.651963 0.0422323 0.329583 4 0.667575 0.678126 0.0308531 0.276557 5 0.687708 0.694657 0.0230252 0.241842 6 0.701077 0.705958 0.0185731 0.209427 7 0.710522 0.714112 0.015431 0.180258 8 0.717499 0.720232 0.0131014 0.154437 9 0.722829 0.724966 0.0111636 0.135789 10 0.727009 0.728717 0.00955924 0.119854 11 0.730356 0.731745 0.00825889 0.105163 12 0.733083 0.734229 0.00726878 0.0917109 13 0.735336 0.736293 0.0064123 0.0794455 14 0.737221 0.738029 0.00574042 0.0682936 15 0.738814 0.739502 0.00514483 0.0581723 16 0.740172 0.740762 0.00461455 0.0495549 17 0.741339 0.741849 0.00414236 0.0426384 18 0.742348 0.742791 0.00372159 0.0364693 19 0.743225 0.743613 0.00334623 0.0308046 20 0.743993 0.744333 0.00301095 0.0268309 21 0.744667 0.744967 0.00271107 0.0290672 22 0.745261 0.745526 0.00244252 0.0310488 23 0.745787 0.746022 0.00220174 0.0328095 24 0.746254 0.746463 0.00198562 0.0343777 25 0.746669 0.746855 0.00179145 0.0357775 26 0.747039 0.747205 0.00161683 0.0370291 27 0.747369 0.747518 0.00145968 0.0381501 28 0.747665 0.747799 0.00131972 0.0391554 29 0.74793 0.74805 0.00119371 0.0400581 30 0.748168 0.748276 0.00107972 0.0408695 31 0.748382 0.748479 0.000976623 0.0417889 POISSON: The iteration has converged POISSON: Normal end of execution.