Is there a technique that would allow ranking each row of a matrix without looping?   So the returned matrix would have within-row ranks.   For example if A held all non-missing numeric data, then imaginary function rowRank(A) would return values 1:ncol(A) in each row.     ... View more

I have several stored matrices named like: DATA01  DATA02  DATA03  DATA04  DATA05... DATA20   I'd like to load and process them one at a time in a loop and I'd like to do this all in IML -- no macro code.   In pseudocode it would look like:   DO i = 1 TO 20;    *** might have to do two loops, one for 01-09 and another for 10-20;      LOAD DATAi;      PRINT "SUM = " (DATA0i[+]);  *** a simple calc;   END;   I've got the matrix names stored in an array but I don't know how to evaluate the array elements in the loop so they resolve to DATA01, etc.   Any tips & suggestions are appreciated. ... View more

Last week I got some help with allocating memory for very large IML arrays. The post got deleted by accident so I thought I'd repost to assist those trying to do that. In short, IML 14.1 supports matrices with up to 2 31 elements on the Windows operating system. I upgraded to 14.1 and have sufficient RAM but a simple "y = j(33000,33000,1);"  wasn't working for me. IIRC, Rick Wicklin suggested adding "-MEMSIZE 12G" to the shortcut I start SAS with. I went a little deeper and edited that configuration into my SASv9.CFG file and now I can allocate large arrays on my Win7 16GB RAM machine. Thanks, Rick! Incidentally, this lets me run much larger Monty Hall simulations -- up to a quarter of a billion sims -- see attached code & results below based on Rick's "DO Loop" Monty Hall example -- and remember to "switch doors"! proc iml; t0 = time(); NumSim = 2.5e8;                             /* number of simulated games */ car = randfun(NumSim, "Table", {1 1 1}/3);  /* unknown door hides car */ guess = j(NumSim, 1, 1);                    /* WLOG, you guess door=1 */ show = choose(car=2, 3, 2);                 /* host shows you a goat --> if car behind 2 then 3 else 2 */ switch = choose(show=2, 3, 2);              /* the door you could switch to -- if host shows 2 then 3 else 2 */ winIfSwitch = mean(switch=car);             /* (P(win | switch) */ winIfStay = mean(guess=car);                /* (P(win | do not switch) */ elapsedTime = time() - t0; print "Monty Hall: NumSim = " NumSim[format=comma12. label=EMPTY]  winIfStay[format=8.6 rowname="   p(WinIfStay)" label=EMPTY] winIfSwitch[format=8.6 rowname="   p(WinIfSwitch)" label=EMPTY]  "   Time in Seconds = " elapsedTime[format=4.1 label=EMPTY]; Monty Hall: NumSim =   250,000,000    p(WinIfStay) 0.333347    p(WinIfSwitch) 0.666653    Time in Seconds =  11.1 ... View more