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I use HPGCC2 and this tutorial to make sum program for 50g.
http://sense.net/~egan/hpgcc/
example, This sum program made in UserRPL looks like this
Code:
```<< -> n << 0. 1. n FOR X X + NEXT >> >>```
It's simple program, which gets stack 1 number and calculate 1 to that number sum.

so, I want to C's speed. I coded this.
Code:
```#include <hpgcc49.h> int main(void) {     // sum 1 to n and counter i     int n, i;     int sum = 0;     // fast mode     sys_slowOff();     // get stack 1 real number     n = sat_pop_real();     // calculate sum     for (i = 1; i <= n; i++) {         sum += i;     }     // output     sat_push_real(sum);     sys_slowOn();     return(0); }```
and based on top tutorial, I made UserRPL wrapper.
Code:
```<< "Input 1 real" -> n << DEPTH IF 0 == THEN u DOERR END 3: "EXTEND/SM" EVAL >> >>```
where "EXTEND/SM" is C program's location.

But I execute this program to calculate 1 to 1000 sum, It gives 499500 instead of 500500. and number goes up over 1000, It gives wrong answer.
ex)
999 -> 499,500 (correct)
1,000 -> 499,500 (incorrect which is 500,500)
1,001 -> 500,500 (incorrect which is 501,501)
2,000 -> 1,999,000 (incorrect which is 2,001,000)
10,000,000 -> -2,001,260,032 (I think it is overflow)

I'm a very noob for C, so my code may be wrong. What's wrong with my program?
From quick testing here, your C code appears to be mostly correct. As you suspected, you're seeing overflows in your output for certain large inputs.
I can't tell what your HP code is doing though, as I've never tried compiling stuff under hpgcc and executing it from the calculator.

This is the C code I used to test that things work, at least on a Linux machine (and probably a Microsoft setup too):

Code:
``` #include <stdio.h> #include <stdlib.h> int main(int argc, char **argv) {   int n, i;   /* Need a bigger value for results above 2e9. May not work for hpgcc2, in this case remove unsigned keyword */   unsigned long long sum=0;   /* Some arg checking first */   if (argc < 2) {     printf("Cannot run with nothing\n");     exit(1);   }   if (argc > 2) {     printf("Too many args; I only need one number.\n");     exit(1);   }   /* Absolutely no checking that argv[1] is an int */   n = atoi(argv[1]);   for (i=1; i<=n; i++) {     sum += i;   }   /* printf need %lld because of the unsigned long long value we're printing       You're putting value back on the stack, so calculator will deal with printing instead */   printf("%lld\n", sum);   exit(0); }```

(Post 336)
(03-13-2021 06:41 AM)BINUBALL Wrote: [ -> ]I use HPGCC2 and this tutorial to make sum program for 50g.
http://sense.net/~egan/hpgcc/
example, This sum program made in UserRPL looks like this
Code:
```<< -> n << 0. 1. n FOR X X + NEXT >> >>```
It's simple program, which gets stack 1 number and calculate 1 to that number sum.

so, I want to C's speed. I coded this.
Code:
```#include <hpgcc49.h> int main(void) {     // sum 1 to n and counter i     int n, i;     int sum = 0;     // fast mode     sys_slowOff();     // get stack 1 real number     n = sat_pop_real();     // calculate sum     for (i = 1; i <= n; i++) {         sum += i;     }     // output     sat_push_real(sum);     sys_slowOn();     return(0); }```
and based on top tutorial, I made UserRPL wrapper.
Code:
```<< "Input 1 real" -> n << DEPTH IF 0 == THEN u DOERR END 3: "EXTEND/SM" EVAL >> >>```
where "EXTEND/SM" is C program's location.

But I execute this program to calculate 1 to 1000 sum, It gives 499500 instead of 500500. and number goes up over 1000, It gives wrong answer.
ex)
999 -> 499,500 (correct)
1,000 -> 499,500 (incorrect which is 500,500)
1,001 -> 500,500 (incorrect which is 501,501)
2,000 -> 1,999,000 (incorrect which is 2,001,000)
10,000,000 -> -2,001,260,032 (I think it is overflow)

I'm a very noob for C, so my code may be wrong. What's wrong with my program?

Just a WAG (wild-ass guess) but could it be that you're putting a real on the stack while your routine expects an integer?
(03-15-2021 10:14 AM)brickviking Wrote: [ -> ]From quick testing here, your C code appears to be correct. I can't tell what your HP code is doing though, as I've never tried compiling stuff under hpgcc and executing it from the calculator.

This is the C code I used to test that things worked:

Code:
``` #include <stdio.h> #include <stdlib.h> int main(int argc, char **argv) {   int n, i, sum=0;   /* Some arg checking first */   if (argc < 2) {     printf("Cannot run with nothing\n");     exit(1);   }   if (argc > 2) {     printf("Too many args; I only need one number.\n");     exit(1);   }   /* Absolutely no checking that argv[1] is an int */   n = atoi(argv[1]);   for (i=1; i<=n; i++) {     sum += i;   }   printf("%d\n", sum);   exit(0); }```

(Post 336)

I've tried with online C editor too and I confirmed there is no error. Program runs well.

(03-15-2021 10:22 AM)toml_12953 Wrote: [ -> ]
(03-13-2021 06:41 AM)BINUBALL Wrote: [ -> ]I use HPGCC2 and this tutorial to make sum program for 50g.
http://sense.net/~egan/hpgcc/
example, This sum program made in UserRPL looks like this
Code:
```<< -> n << 0. 1. n FOR X X + NEXT >> >>```
It's simple program, which gets stack 1 number and calculate 1 to that number sum.

so, I want to C's speed. I coded this.
Code:
```#include <hpgcc49.h> int main(void) {     // sum 1 to n and counter i     int n, i;     int sum = 0;     // fast mode     sys_slowOff();     // get stack 1 real number     n = sat_pop_real();     // calculate sum     for (i = 1; i <= n; i++) {         sum += i;     }     // output     sat_push_real(sum);     sys_slowOn();     return(0); }```
and based on top tutorial, I made UserRPL wrapper.
Code:
```<< "Input 1 real" -> n << DEPTH IF 0 == THEN u DOERR END 3: "EXTEND/SM" EVAL >> >>```
where "EXTEND/SM" is C program's location.

But I execute this program to calculate 1 to 1000 sum, It gives 499500 instead of 500500. and number goes up over 1000, It gives wrong answer.
ex)
999 -> 499,500 (correct)
1,000 -> 499,500 (incorrect which is 500,500)
1,001 -> 500,500 (incorrect which is 501,501)
2,000 -> 1,999,000 (incorrect which is 2,001,000)
10,000,000 -> -2,001,260,032 (I think it is overflow)

I'm a very noob for C, so my code may be wrong. What's wrong with my program?

Just a WAG (wild-ass guess) but could it be that you're putting a real on the stack while your routine expects an integer?

That's a good guess. But I tried with integer 100, it gives 100 0. , therefore it doesn't compute sum.
Can you try to just pop/push and see if the input and output are the same? I agree it may be a float/int thing.

Also for int use n = sat_pop_zint_llong();

Try that.
(03-15-2021 05:55 PM)Egan Ford Wrote: [ -> ]Can you try to just pop/push and see if the input and output are the same? I agree it may be a float/int thing.

Also for int use n = sat_pop_zint_llong();

Try that.

Code:
```#include <hpgcc49.h> int main(void) {     int n;     // get stack 1 real number     n = sat_pop_real();     // output     sat_push_real(n);     return(0); }```

I wrote that code and bug happens too. 1000 -> 999, 1001 -> 1000..

Then what I have to use instead of sat_push_real()?
sat_push_zint()?
sat_push_zint_llong()?
And, where can I find hpgcc2 functions?
Did you try to format sum and n as a long integer?
First thing you should try is to use hpgcc3 instead of hpgcc 2.0. It has several additional years of bug-fixing and a much more polished API to create/pop/push objects to the stack.
It works properly with zint, thank you for everyone.
And, here is my last source code.
Code:
```#include <hpgcc49.h> int main(void) {     // sum 1 to n and counter i     int n, i;     int sum = 0;     // fast mode     sys_slowOff();     // get stack 1 zint     n = sat_pop_zint_llong();     // calculate sum     for (i = 1; i <= n; i++) {         sum += i;     }     // output     sat_push_zint_llong(sum);     sys_slowOn();     return(0); }```
(03-16-2021 03:34 AM)BINUBALL Wrote: [ -> ]And, where can I find hpgcc2 functions?

Try here:

https://web.archive.org/web/200904100244...hpgcc.org/
(03-16-2021 04:20 PM)Claudio L. Wrote: [ -> ]First thing you should try is to use hpgcc3 instead of hpgcc 2.0. It has several additional years of bug-fixing and a much more polished API to create/pop/push objects to the stack.

Does hpgcc3 still require a custom ROM?
(03-18-2021 05:02 PM)Egan Ford Wrote: [ -> ]Does hpgcc3 still require a custom ROM?

Yes, which is no big deal at all (never was).
The OP posted a few things about newRPL, so I don't think he's nervous about running custom ROMS (if he trusted me to completely replace his firmware, what could go wrong with a couple tiny hacks...).
(03-19-2021 02:51 PM)Claudio L. Wrote: [ -> ]
(03-18-2021 05:02 PM)Egan Ford Wrote: [ -> ]Does hpgcc3 still require a custom ROM?

Yes, which is no big deal at all (never was).
The OP posted a few things about newRPL, so I don't think he's nervous about running custom ROMS (if he trusted me to completely replace his firmware, what could go wrong with a couple tiny hacks...).
Does HPGCC3 completely replace stock rom like newRPL? And can I go back stock rom whenever I want?
Trying HPGCC3 may not be bad for me.
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