Nosing around in cu.c I find

static DF1(jtundco1){DECLFG; R df1( w,atop(inv(gs),ampco(fs,gs)));}

This is the routine that executes on the verb derived from u&.:v .

What I don't understand is why the calculation of the inverse and &: and @ are not performed before the derived verb is created. That result could be stored in h, which would shorten this code to

static DF1(jtundco1){DECLFGH; R df1(  w,hs);}

As it is, the inverse calculation etc are performed every time the verb is executed on data.

Can anyone show cause why this calculation should not be performed during the execution of &.: rather than in the derived verb?


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