splitmon: added optional parameter to set the format string for the month

ChangeLog

@@ -5,6 +5,7 @@
 
 2013-10-21  Uwe Schulzweida  <Uwe.Schulzweida@zmaw.de>
 
+	* splitmon: added optional parameter to set the format string for the month [Feature #4131]
 	* Sort: added support for multi level variables (bug fix) [report: Irina Fast]
 
 2013-10-18  Uwe Schulzweida  <Uwe.Schulzweida@zmaw.de>

NEWS

@@ -6,6 +6,7 @@ Version 1.6.2 (27 September 2013):
    New features:
      * select: added support for key >timestep_of_year<
      * mastrfu: added missing value support
+     * splitmon: added optional parameter to set the format string for the month
    Fixed bugs:
      * selyear: wrong result for negative years [Bug #3836]
 

OPERATORS

@@ -54,9 +54,9 @@ Operator catalog:
    Split         splittabnum     Split parameter table numbers
    Splittime     splithour       Split hours
    Splittime     splitday        Split days
-   Splittime     splitmon        Split months
    Splittime     splitseas       Split seasons
    Splittime     splityear       Split years
+   Splittime     splitmon        Split months
    Splitsel      splitsel        Split time selection
 -------------------------------------------------------------
    Selection

doc/tex/mod/Splittime

@@ -5,7 +5,7 @@
 @Section   = File operations
 @Class     = File operation
 @Arguments = ifile obase
-@Operators = splithour splitday splitmon splitseas splityear
+@Operators = splithour splitday splitseas splityear splitmon
 
 @BeginDescription
 This module splits @file{ifile} into  timesteps pieces. The output files will be named
@@ -37,6 +37,7 @@ Splits a file into pieces, one for each different day.
 
 @BeginOperator_splitmon
 @Title     = Split months
+@Parameter = [format]
 
 @BeginDescription
 Splits a file into pieces, one for each different month.
@@ -65,6 +66,12 @@ Splits a file into pieces, one for each different year.
 @EndOperator
 
 
+@BeginParameter
+@Item = format
+STRING  C-style format for strftime() (e.g. \%B for the full month name)
+@EndParameter
+
+
 @BeginEnvironment
 @Item = CDO_FILE_SUFFIX
 This environment variable can be used to set the default file suffix. This suffix will be

src/Splittime.c

@@ -30,9 +30,29 @@
 #include "pstream.h"
 #include "util.h"
 
+#include <time.h>
 
 #define  MAX_STREAMS 32
 
+struct tm datetime_to_tm(int date, int time)
+{
+  int year, month, day, hour, minute, second;
+  cdiDecodeDate(date, &year, &month, &day);
+  cdiDecodeTime(time, &hour, &minute, &second);
+
+  struct tm stime;
+  memset(&stime, 0, sizeof(struct tm));
+
+  stime.tm_sec  = second;
+  stime.tm_min  = minute;
+  stime.tm_hour = hour;
+  stime.tm_mday = day;
+  stime.tm_mon  = month-1;
+  stime.tm_year = year-1900;
+
+  return stime;
+}
+
 void *Splittime(void *argument)
 {
   int SPLITHOUR, SPLITDAY, SPLITMON, SPLITSEAS;
@@ -62,6 +82,7 @@ void *Splittime(void *argument)
   field_t **vars = NULL;
   int season_start;
   const char *seas_name[4];
+  const char *format = NULL;
 
   cdoInitialize(argument);
 
@@ -76,6 +97,11 @@ void *Splittime(void *argument)
 
   if ( UNCHANGED_RECORD ) lcopy = TRUE;
 
+  if ( operatorID == SPLITMON )
+    {
+      if ( operatorArgc() == 1 ) format = operatorArgv()[0];
+    }
+
   season_start = get_season_start();
   get_season_name(seas_name);
 
@@ -188,9 +214,22 @@ void *Splittime(void *argument)
 	    }
 	  else
 	    {
-	      sprintf(filename+nchars, "%02d", index);
+	      char oformat[32];
+	      strcpy(oformat, "%02d");
+
+	      if ( operatorID == SPLITMON && format )
+		{
+		  size_t slen;
+		  char sbuf[32];
+		  struct tm stime = datetime_to_tm(vdate, vtime);
+		  slen = strftime(sbuf, 32, format, &stime);
+
+		  if ( slen ) strcpy(oformat, sbuf);
+		}
+
+	      sprintf(filename+nchars, oformat, index);
 	      if ( filesuffix[0] )
-		sprintf(filename+nchars+2, "%s", filesuffix);
+		sprintf(filename+nchars+strlen(oformat), "%s", filesuffix);
 	    }
 
 	  if ( cdoVerbose ) cdoPrint("create file %s", filename);

src/operator_help.h

@@ -329,11 +329,12 @@ static char *SplitHelp[] = {
 
 static char *SplittimeHelp[] = {
     "NAME",
-    "    splithour, splitday, splitmon, splitseas, splityear - ",
+    "    splithour, splitday, splitseas, splityear, splitmon - ",
     "    Split timesteps of a dataset",
     "",
     "SYNOPSIS",
     "    <operator>  ifile obase",
+    "    splitmon[,format]  ifile obase",
     "",
     "DESCRIPTION",
     "    This module splits ifile into  timesteps pieces. The output files will be named",
@@ -347,15 +348,18 @@ static char *SplittimeHelp[] = {
     "    splitday   Split days",
     "               Splits a file into pieces, one for each different day.",
     "               xxx will have two digits with the day.",
-    "    splitmon   Split months",
-    "               Splits a file into pieces, one for each different month.",
-    "               xxx will have two digits with the month.",
     "    splitseas  Split seasons",
     "               Splits a file into pieces, one for each different season.",
     "               xxx will have three characters with the season.",
     "    splityear  Split years",
     "               Splits a file into pieces, one for each different year.",
     "               xxx will have four digits with the year.",
+    "    splitmon   Split months",
+    "               Splits a file into pieces, one for each different month.",
+    "               xxx will have two digits with the month.",
+    "",
+    "PARAMETER",
+    "    format  STRING  C-style format for strftime() (e.g. %B for the full month name)",
     "",
     "ENVIRONMENT",
     "    CDO_FILE_SUFFIX",