Re: Calculation in SNL/SEQ

["Kotturi, Dayle" <dayle@slac.stanford.edu>]

Having just learned about pVar pointer from my colleague Kukhee Kim, I can also offer that,
in addition to adding '%%#include "math.h"' and prepending lines with c function calls with '%%', 
you may also need to help the escaped c code access the SNL variables via the pVar pointer.
  
       r1=1.0;
        r2=2.0;
        %%pVar->temp=fabs(pVar->r1-pVar->r2);
        printf("fabs:  %lf\n",temp);
        %%pVar->temp=exp(pVar->r1+pVar->r2);
        printf("exp:  %lf\n", temp);  

Without the 'pVar->', you may see these errors:
error: `temp' undeclared (first use in this function)
error: `r1' undeclared (first use in this function)
error: `r2' undeclared (first use in this function)

Dayle

On May 10, 2011, at 8:26 PM, Chestnut, Ronald P. wrote:

> Dear Liuping,
> 
> You have to include the math libraries, as  you would for a simple "C" program.
> 
> If SNL doesn't parse the libraries correctly, escape them and their use with %%.
> 
> %%include math.h
> 
> 
> %%temp=fabs(r1-r2);
> 
> Ron
> 
> On May 10, 2011, at 7:35 PM, liuping wrote:
> 
> Hello,
> I need your help about the calculation in SNL/SEQ.
> In my SNL/SEQ application, I need to execute the mathematical operation: fabs() and exp().
> Here is the codes abstracted from the my application:
> %%/////////////////////
> double   temp;
>  double  err;
>  double  r1;
>  double  r2;
> 
>  ss test123{
>         state calctest
>        {
>           when(delay(2))
>           {
>                r1=1.0;
>               r2=2.0;
>                temp=fabs(r1-r2);
>                printf("fabs:  %lf\n",temp);
>                temp=exp(r1+r2);
>                printf("exp:  %lf\n", temp);
>           } state calctest
>        }
>   }
> %%//////////////////////////
> 
> The operation result is:
> fabs:  1.000000
> exp:  2287528.000000
> fabs:  1.000000
> exp:  2287528.000000
> fabs:  1.000000
> exp:  2287528.000000
> ……
> Obviously, the result of “fabs” is right, and the other is wrong. Then I check the output of compiler. There are two warning and no error (see the bold and incline words).
> .....
> make[3]: Entering directory `/home/blctrl/watercool-Mono/motorApp/OmsSrc/O.vxWorks-ppc604_long'
> converting ../sncExample.stt
> /home/blctrl/seq-2.0.11/bin/linux-x86/snc    ../sncExample.stt -o sncExample.c.tmp
> mv sncExample.c.tmp sncExample.c
> /BLC/epics/Tornado2.2/host/x86-linux/bin/ccppc -c   -D_POSIX_SOURCE       -DCPU=PPC604  -DvxWorks -include /BLC/epics/Tornado2.2/target/h/vxWorks.h  -ansi  -O3  -Wall     -mcpu=604 -mstrict-align -mlongcall    -fno-builtin  -I. -I.. -I../../../include/os/vxWorks -I../../../include -I/home/blctrl/asyn4-8/include/os/vxWorks -I/home/blctrl/asyn4-8/include -I/home/blctrl/seq-2.0.11/include/os/vxWorks -I/home/blctrl/seq-2.0.11/include -I/BLC/epics/base/include/os/vxWorks -I/BLC/epics/base/include      -I/BLC/epics/Tornado2.2/target/h  sncExample.c
> ../sncExample.stt: In function `A_test123_calctest':
> ../sncExample.stt:38: warning: implicit declaration of function `fabs'
> ../sncExample.stt:40: warning: implicit declaration of function `exp'
> perl /BLC/epics/base/bin/linux-x86/registerRecordDeviceDriver.pl ../O.Common/omsMAXv.dbd omsMAXv_registerRecordDeviceDriver > temp.cpp
> mv temp.cpp omsMAXv_registerRecordDeviceDriver.cpp
> .....
> 
> Again, I tried to do such process:
> 1)Power off the VME rack,
> 2)Change the value of r1 and r2:    r1=9.0;    r2=12.0;
> 3)make clean
> 4)make
> 5)Power on the VME rack
> 
> Sadly I saw the result was same to last test:
> fabs:  1.000000
> exp:  2287528.000000
> fabs:  1.000000
> exp:  2287528.000000
> fabs:  1.000000
> exp:  2287528.000000
> ……
> The result of “fabs” and “exp” are both wrong. Who can tell me the reason and how to get the right result?
> Any advices are appreciated!
> 
> ===================================
> 
> LIU Ping
> 
> Beamline Control Group
> Shanghai Synchrotron Radiation Facility
> Shanghai Institute of Applied Physics
> Chinese Academy of Sciences
> Zhangheng Rd 239,Pudong Dist.,
> Shanghai 201204
> China
> Tel:+86-21-33933237(Lab)
> 
> http://ssrf.sinap.ac.cn<http://ssrf.sinap.ac.cn/>
> ===================================
> 
> 
>