1961    int e_ind, w_ind, n_ind, s_ind;  in num_valid_8nbrs()  local
1969    w_ind = mx-1;  /* West index */  in num_valid_8nbrs()
1975    if((w_ind >= 0) && (n_ind >= 0) && (*(imap + (n_ind*mw) + w_ind) >= 0))  in num_valid_8nbrs()
2000    if((w_ind >= 0) && (s_ind < mh) && (*(imap + (s_ind*mw) + w_ind) >= 0))  in num_valid_8nbrs()
2004    if((w_ind >= 0) && (*(imap + (my*mw) + w_ind) >= 0))  in num_valid_8nbrs()
2114    int e_ind, w_ind, n_ind, s_ind;  in vorticity()  local
2120    w_ind = mx-1;  /* West index */  in vorticity()
2126    if((w_ind >= 0) && (n_ind >= 0))  in vorticity()
2128       nw_val = *(imap + (n_ind*mw) + w_ind);  in vorticity()
2164    if((w_ind >= 0) && (s_ind < mh))  in vorticity()
2165       sw_val = *(imap + (s_ind*mw) + w_ind);  in vorticity()
2170    if(w_ind >= 0)  in vorticity()
2171       w_val = *(imap + (my*mw) + w_ind);  in vorticity()
2275    int e_ind, w_ind, n_ind, s_ind;  in curvature()  local
2281    w_ind = mx-1;  /* West index */  in curvature()
2287    if((w_ind >= 0) && (n_ind >= 0))  in curvature()
2289       nw_val = *(imap + (n_ind*mw) + w_ind);  in curvature()
2325    if((w_ind >= 0) && (s_ind < mh))  in curvature()
2326       sw_val = *(imap + (s_ind*mw) + w_ind);  in curvature()
2331    if(w_ind >= 0)  in curvature()
2332       w_val = *(imap + (my*mw) + w_ind);  in curvature()