Sharp PC-1403 - Page 89

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• For e x amp l e, i f DIM Z$ (2,3}*10 i s s peci fi e d, 1 2 v ariab l e s , ea c h c apabl e of
s t oring 1 O cha ra c t e rs, are r es e rv ed . T hi s r e q u i r e s 7 bytes ( v aria b le name) + 10
bytes (numb er of ch arac te rs) x 1 2 = 1 27 b y t e s .
Va ria b le
Variab l e n ame
Da t a
Num e r ic v ar i a b l e
7 by t e s
8 b ytes
A rray v ariab l e S pe ci fied n umb er
Stri ng var iable
7 by t es
Si mp le v a r iab l e
( two-char a cter
16 bytes
v a r i a bl e )
No te : Two-dimens i ona l a rr a y s c an ra pi d l y eat up st orage s p ace . For example, an
array with 2 5 r ows an d 3 5 co l umn s u ses 87 5 st orage lo c ati o ns!
Arrays are very powe rf u l p rog r am m in g to o l s .
The follow i ng t ab l e sho w s th e nu mbe r o f by t e s u sed t o de f i ne ea c h var i able and th e
number u sed by eac h p ro gr a m state me nt.
Row2
Rowl
I
T (0. 0 )
T (0, 1)
I
T (0 , 2 ) TIO , 3)
I I
T ( 1 . 0 )
T ( 1 , 1)
T ( 1 , 2)
T (1, 3)
T ( 2 , 0 )
T ( 2 , 1 )
T (2 , 2 )
T (2, 3)
RowO
Co lumn4
Colu m n3
Co lumn 2
Columnl
DIM ch arac ter - var i ab l e - n a m e (r ows , c o l u m ns)*len g th
whe re :
rows s p e cifies th e n umber o f r ow s i n t h e ar r a y . T h i s mu st b e a numbe r i n th e ra ng e O
th ro u g h 25 5 . N o te tha t when y o u s pec if y t he numbe r of rows y ou ge t one mo re r ow
tha n th e sp ec i ficat i o n .
c o lu m n s specifi e s the nu mbe r o f co l u mns i n t he a rr a y . T his mu st be a num ber i n th e
ra n ge O thro u gh 255 . No t e t h a t w he n you s pecify the nu mb er o f co lu mns y ou ge t
o n e more col u mn t h an the s p e ci fic a t i o n .
Th e f o ll ow i ng diagr a m ill u st r ates t h e sto rage l ocations th at r esu lt fr om t h e de c laration
DIM T (2 , 3 ) a nd t he s ubscr i pts (now composed o f t w o number s } tha t pe rtai n t o ea c h
storage l o ca t ion :
or
DIM numer i c-v a riable- n ame ( ro w s , c o lu mn s }
C on c ept s a nd T e rm s of BASIC