Remote-processing CAMBASIC Bedienungsanleitung PDF herunterladen (Seite 25)

Program ing Tips - 2

can use PC SmartLINK to strip out the remar ks in the final program. H owever, this may have a significant

impact on clarity. Do this only if all other methods fail.

10. Spaces have no affect on speed since they are eliminated in the compiling process.

11. Data statements execute slowly. If you need large data tables, load them into RAM at the start of the

program, and access them with the PEEK function. While this is less convenient, it is faster.

12. The PRIN T USING statement takes longer to execute than PRINT, as it must format before sending the

characters.

13. FPOKE and FPEEK are the fastest memory accesses. T hey move four bytes at a time. If you have enough

memory to store multiple bytes, then use these constructs rather than PEEK, POKE, DPEEK and DPOKE.

FPOKE A%,B% is more than twice as fast as

POKE A,B in an average program

14. Array handling is, by its nature, slow in any language. Avoid multi-dimension arrays when possible.

15. When possible, use the DO/ENDDO loop instead of the FOR/NEXT. It is much faster.

16. The m ost effective w ay to speed up a progr am is through good progr amming. Highly m odular pr ogram s with

lots of subroutines and GOSUBs are easy to develop, read and maintain. However, they are slower than

optimizing program flow for speed.

17. When using a FOR/NEXT loop, avoid placing the variable after NEXT. This forces CAM BASIC to verify

the variable name and slow down execution of the loop.

10 NEXT fast

10 NEXT D slow

18. Do not use exponent to square or cube a number. It is a very slow operation.

10 A=X$2 very slow

10 A=X*X fast

10 A=X*X*X better than x$3

Other Tips

1. Sometimes a system will crash without any obvious cause. The crashing can occur because part of the

memory used by CAM BASIC has been modified by a POKE statement that is out of bounds. For example,

10 POKE A,B

The variable A is the address at which the POKE occurs. If the value of A inadvertently falls into the wrong

area, unpredictable results may occur. Some of these are:

a. Error message for a nonexistent line number.

1 2 ... 20 21 22 23 24 25 26 27 28 29 30 ... 207 208

Keine Kommentare

Remote-processing CAMBASIC Bedienungsanleitung Seite 25