Re: TI89 very slow !!!


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Re: TI89 very slow !!!



...
>fct1(10000) takes 85 sec to display 10001
...
TI-86 rom 1.2 on the main screen:
For(x,1,10000:End:x took 45 secs. - try and let's compare


>
>fct2(10000) takes 140 sec to display 10000.
For(x,1,10000:x->t:End:t took 195 secs.

 Even
>the HP48 with its 4 bits saturn processor goes faster !
>

Examples, please!

>And about memory:
>seq(t,t,1,1000) takes 8 sec to display the list of {1 2 ... 1000}

20s

>and is it incredibly slow to delete and copy lists of 1000 elements.

How do you do? I think Delvar( is incredibly fast.
>
>seq(t,t,1,1000)->t1     19s 10009 bytes, with 999 elements the it is 9999
0->dimL t1 took less than 0.8s whereas Delvar(t1 took less than 0.5s


5635->dimL t creates a 56359 bytes list!!! in 7s
and if just one element is a complex number the size is almost doubled! Hey
TI - ever though about identity bytes?

>Your opinion ?


10 bytes to store a number in a list is simply too much. 2^8^10=1.21E24
possibilities - 9^13=2.54E12=2^8^5.15 so 6 bytes a number should be an
absolute maximum and indeed it would still be an incredible waste of memory,
since most numbers are not 13 digits long.

The TI-calcs know of ten datatypes, so 4 bit should be enough to describe
the datatype. Then we could add one byte per character in the name, 4 bit to
separate each element, 4 bit to tell the length of the following element,
and 6 bytes to tell the length of the list.

The list X={8} would then take up nine bytes where TI uses nineteen!

Kasper


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