// Example linear transformation function for contour plotter. // #include "plplotP.h" extern PLFLT tr[]; void xform( PLFLT x, PLFLT y, PLFLT * tx, PLFLT * ty ) { *tx = tr[0] * x + tr[1] * y + tr[2]; *ty = tr[3] * x + tr[4] * y + tr[5]; }