Texas Instruments TI-89 Tip List page 210

title "INPUT ERROR"
text "Entry error for"
text msg
text "Push ENTER to try again"
enddlog
EndPrgm
©Create lists & matrix
newlist(3)→xl
newlist(3)→yl
newmat(3,3)→zmat
©Initialize variables
"0,0,0"→x123
"0,0,0"→y123
"0,0,0"→zz1
"0,0,0"→zz2
"0,0,0"→zz3
"0,0"→xy
1→inhome
Lbl in1
©Prompt for input variables
dialog
title "INTRP9UI"
request "x1,x2,x3",x123
request "y1,y2,y3",y123
request "z row 1",zz1
request "z row 2",zz2
request "z row 3",zz3
request "x,y",xy
enddlog
if ok=0:return
©Extract x-variables
util\rq3v(x123)→res
if res="ERR" then
errdisp("x1,x2,x3")
if ok=0 then
return
else
goto in1
endif
else
res[1]→xl[1]
res[2]→xl[2]
res[3]→xl[3]
endif
©Extract y-variables
util\rq3v(y123)→res
if res="ERR" then
errdisp("y1,y2,y3")
if ok=0 then
return
else
goto in1
endif
else
res[1]→yl[1]
res[2]→yl[2]
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