Re: Using HDF5 to create an R data frame

[Marcus G. Daniels]

>>>>> "LRA" == M Lang & S Railsback <address@hidden> writes:

LRA> Hmm, this example seems to be for reading data into Swarm, not
LRA> archiving a Swarm list.

Below is an example that demonstrates loading and saving Lists and
Maps using shallow serialization.  In the HDF5 configuration, the data
can be recovered as a R data frame.  (The default configuration is for
List and HDF5, i.e. the absence of -DUSE_MAP and the presence of -DUSE_HDF5
in the compile-command.)

To save data use:
   ./collectionArchiving -m create

To load it, use:
   
   ./collectionArchiving

To load it in R 1.0, use:

    library(hdf5) # need to load the HDF5 module
    hdf5load("collection.hdf") # load the file specified per the code below
    myCollection # the variable it is loaded to per the code below

Saving in R is as below.  Note that the need to specify variable names
as quoted strings.

    x <- 1 # assign 1 to "x"
    hdf5save("newCollection.hdf", "myCollection", "x")

LRA> I'm not finding it in the version distributed on the Swarm 2.1
LRA> CD- either via the Help command or in the extensive reference
LRA> manual. 

Did you install the HDF5 module and do "library(hdf5)" upon R startup?

#import <simtools.h> // initSwarm
#import <defobj.h> // Archivers
#import <defobj/Create.h> // CreateDrop
#import <defobj/defalloc.h> // getZone

@interface Data: CreateDrop
{
#ifndef USE_MAP
  const char *date;
#endif
  double value;
}
#ifndef USE_MAP
- setDate: (const char *)date;
- (void)describe: stream;
#else
- (double)getValue;
#endif
- setValue: (double)value;
@end

@implementation Data
#ifndef USE_MAP
- setDate: (const char *)theDate
{
  date = STRDUP (theDate);
  return self;
}
#endif

- setValue: (double)theValue
{
  value = theValue;
  return self;
}

#ifndef USE_MAP
- (void)describe: stream
{
  [stream catC: "Date: "];
  [stream catC: date];
  [stream catC: " Value: "];
  [stream catDouble: value];
  [stream catC: "\n"];
}
#else
- (double)getValue
{
  return value;
}
#endif

@end

@interface Controller: CreateDrop
{
  id collection;
}
#ifdef USE_MAP
- (void)createMap;
#else
- (void)createList;
#endif
@end

#define NAME "myCollection"

@implementation Controller

#ifdef USE_MAP
- (void)createMap
{
#define DATA(value) [[Data createBegin: getZone (self)] setValue: value]
  collection = [[[Map createBegin: getZone (self)]
            setCompareCStrings]
           createEnd];
  [collection at: (id) "1999-01-01" insert: DATA(1.0)];
  [collection at: (id) "1999-01-02" insert: DATA(2.0)];
  [collection at: (id) "1999-12-31" insert: DATA(3.0)];
}
#else
#define DATA(date,value) \
  [[[Data createBegin: getZone (self)] setDate: date] setValue: value]

- (void)createList
{
  collection = [List create: getZone (self)];
  [collection addLast: DATA ("1999-01-01", 1.0)];
  [collection addLast: DATA ("1999-01-02", 2.0)];
  [collection addLast: DATA ("1999-12-31", 3.0)];
}
#endif

- updateArchiver: archiver
{
  [archiver putShallow: NAME object: collection];
  return self;
}
@end

int
main (int argc, const char **argv) 
{
  initSwarmBatch (argc, argv);

  {
    id archiver;
    id controller;

#ifdef USE_HDF5
    archiver = [[[HDF5Archiver createBegin: globalZone]
                  setPath: "collection.hdf"]
                 createEnd];
#else
    archiver = [[[LispArchiver createBegin: globalZone]
                  setPath: "collection.scm"]
                 createEnd];
#endif
    controller = [Controller create: globalZone];

    if (strcmp ([arguments getAppModeString], "create") == 0)
      {
#ifdef USE_MAP
        [controller createMap];
#else
        [controller createList];
#endif
        [archiver registerClient: controller];
        [archiver sync];
      }
    else
      {
#ifdef USE_MAP
        id collection, index, obj, key;

        collection = [archiver getObject: NAME];
        if (collection)
          {
            index = [collection begin: scratchZone];
            
            for (obj = [index next: &key];
                 [index getLoc] == Member;
                 obj = [index next: &key])
              {
                printf ("Date: %s Value: %f\n",
                        (const char *) key,
                        [obj getValue]);
              }
            [index drop];
          }
#else
        xfprint ([archiver getObject: NAME]);
#endif
      }
  }
  return 0;
}

/*
Local Variables:
compile-command: "gcc -DDLL -DUSE_HDF5 -o collectionArchiving -g -Wno-import 
-I$SWARMHOME/include -L$SWARMHOME/lib collectionArchiving.m -lswarmdll 
-lobjcdll"
End:
*/

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