 | | Incorrect result —Robert Templeton
|
| | | This problem, unlike the other, is definitely not a result of my eyes/brain being tired or something. I thoroughly displayed every value before and after evaluation and the result is ***WRONG***. Here is the code and the values: typedef struct { int (...) (22 years ago, 30-Jan-02, to lugnet.robotics.rcx.legos)
|
| | | |
| | | | | RE: Incorrect result —Ralph Hempel
|
| | | | | <snipped code> (...) Robert, this is a classic problem with ranges of singed numbers in C rx = (long)(a->magnitude * TA_costable[a->direction]) >> 7; I don't have an RCX in frot of me, but I think you need to cast a->magnitude to long before the (...) (22 years ago, 30-Jan-02, to lugnet.robotics.rcx.legos)
|
| | | | | |
| | | | | | | Re: Incorrect result —Robert Templeton
|
| | | | | | (...) Yes, this is what happens when one is used to just making everything long and not considering overflows. Even worse was that I was doing the math on the computer's calculator, but not looking at the intermediate result, just typing in the (...) (22 years ago, 30-Jan-02, to lugnet.robotics.rcx.legos)
|
| | | | | | |
| | | | | Re: Incorrect result —Michael Obenland
|
| | | | (...) 256 * 128 = 32768, one higher as the biggest positive integer value. The cast to long would help, but your cast is too late. I have not tested, but I think rc += ( (long)b->magnitude * (long)TA_costable[...] ) >> 7; will help. Try output in (...) (22 years ago, 30-Jan-02, to lugnet.robotics.rcx.legos)
|
| | | | |
