move date2num() convernience function from Universe class to utils namespace

doc/src/pg_developer.rst

@@ -902,6 +902,9 @@ Convenience functions
 .. doxygenfunction:: timespec2seconds
    :project: progguide
 
+.. doxygenfunction:: date2num
+   :project: progguide
+
 ---------------------------
 
 Tokenizer classes

src/universe.cpp

@@ -27,8 +27,6 @@ using namespace LAMMPS_NS;
 
 #define MAXLINE 256
 
-static char *date2num(const char *version);
-
 /* ----------------------------------------------------------------------
    create & initialize the universe of processors in communicator
 ------------------------------------------------------------------------- */
@@ -36,7 +34,9 @@ static char *date2num(const char *version);
 Universe::Universe(LAMMPS *lmp, MPI_Comm communicator) : Pointers(lmp)
 {
   version = (const char *) LAMMPS_VERSION;
-  num_ver = date2num(version);
+  auto tmp_ver = new char[10];
+  snprintf(tmp_ver,10,"%08d",utils::date2num(version));
+  num_ver = tmp_ver;
 
   uworld = uorig = communicator;
   MPI_Comm_rank(uworld,&me);
@@ -237,43 +237,3 @@ int Universe::consistent()
   if (n == nprocs) return 1;
   else return 0;
 }
-
-// helper function to convert the LAMMPS date string to a version id
-// that can be used for both string and numerical comparisons
-// where newer versions are larger than older ones.
-
-char *date2num(const char *version)
-{
-  int day,month,year;
-  day = month = year = 0;
-
-  if (version) {
-
-    day = atoi(version);
-
-    while (*version != '\0' && (isdigit(*version) || *version == ' '))
-      ++version;
-
-    if (strncmp(version,"Jan",3) == 0) month = 1;
-    if (strncmp(version,"Feb",3) == 0) month = 2;
-    if (strncmp(version,"Mar",3) == 0) month = 3;
-    if (strncmp(version,"Apr",3) == 0) month = 4;
-    if (strncmp(version,"May",3) == 0) month = 5;
-    if (strncmp(version,"Jun",3) == 0) month = 6;
-    if (strncmp(version,"Jul",3) == 0) month = 7;
-    if (strncmp(version,"Aug",3) == 0) month = 8;
-    if (strncmp(version,"Sep",3) == 0) month = 9;
-    if (strncmp(version,"Oct",3) == 0) month = 10;
-    if (strncmp(version,"Nov",3) == 0) month = 11;
-    if (strncmp(version,"Dec",3) == 0) month = 12;
-
-    while (*version != '\0' && !isdigit(*version))
-      ++version;
-
-    year = atoi(version);
-  }
-
-  char *ver = new char[12];
-  snprintf(ver,12,"%04d%02d%02d", year % 10000, month, day % 100);
-  return ver;
-}

src/utils.cpp

@@ -983,6 +983,34 @@ double utils::timespec2seconds(const std::string &timespec)
   return vals[0];
 }
 
+/* ----------------------------------------------------------------------
+   convert a LAMMPS version date (1Jan01) to a number
+------------------------------------------------------------------------- */
+
+int utils::date2num(const std::string &date)
+{
+  std::size_t found = date.find_first_not_of("0123456789 ");
+  int num = strtol(date.substr(0,found).c_str(),NULL,10);
+  auto month = date.substr(found);
+  found = month.find_first_of("0123456789 ");
+  num += strtol(month.substr(found).c_str(),NULL,10)*10000;
+  if (num < 1000000) num += 20000000;
+
+  if (strmatch(month,"^Jan")) num += 100;
+  else if (strmatch(month,"^Feb")) num += 200;
+  else if (strmatch(month,"^Mar")) num += 300;
+  else if (strmatch(month,"^Apr")) num += 400;
+  else if (strmatch(month,"^May")) num += 500;
+  else if (strmatch(month,"^Jun")) num += 600;
+  else if (strmatch(month,"^Jul")) num += 700;
+  else if (strmatch(month,"^Aug")) num += 800;
+  else if (strmatch(month,"^Sep")) num += 900;
+  else if (strmatch(month,"^Oct")) num += 1000;
+  else if (strmatch(month,"^Nov")) num += 1100;
+  else if (strmatch(month,"^Dec")) num += 1200;
+  return num;
+}
+
 /* ------------------------------------------------------------------ */
 
 extern "C" {

src/utils.h

@@ -371,6 +371,24 @@ namespace LAMMPS_NS {
      * \return total in seconds
      */
     double timespec2seconds(const std::string &timespec);
+
+    /** Convert a LAMMPS version date to a number
+     *
+     * This will generate a number YYYYMMDD from a date string
+     * (with or without blanks) that is suitable for numerical
+     * comparisons, i.e. later dates will generate a larger number.
+     *
+     * The day may or may not have a leading zero, the month
+     * is identified by the first 3 letters (so there may be more)
+     * and the year may be 2 or 4 digits (the missing 2 digits will
+     * be assumed as 20. That is 04 corresponds to 2004).
+     *
+     * No check is made whether the date is valid.
+     *
+     * \param  date  string in the format (Day Month Year)
+     * \return       date code
+     */
+    int date2num(const std::string &date);
   }
 }
 

unittest/utils/test_utils.cpp

@@ -611,3 +611,20 @@ TEST(Utils, timespec2seconds_hhmmss)
 {
     ASSERT_DOUBLE_EQ(utils::timespec2seconds("2:10:45"), 7845.0);
 }
+
+
+TEST(Utils, date2num)
+{
+    ASSERT_EQ(utils::date2num("1Jan05"),20050101);
+    ASSERT_EQ(utils::date2num("10Feb2005"),20050210);
+    ASSERT_EQ(utils::date2num("02Mar10"),20100302);
+    ASSERT_EQ(utils::date2num(" 5Apr1900"),19000405);
+    ASSERT_EQ(utils::date2num("10May22 "),20220510);
+    ASSERT_EQ(utils::date2num("1 Jun 05"),20050601);
+    ASSERT_EQ(utils::date2num("10 Jul 2005"),20050710);
+    ASSERT_EQ(utils::date2num("02 Aug 10"),20100802);
+    ASSERT_EQ(utils::date2num("  5  September  99"),20990905);
+    ASSERT_EQ(utils::date2num("10October22 "),20221010);
+    ASSERT_EQ(utils::date2num("30November 02"),20021130);
+    ASSERT_EQ(utils::date2num("31December100"),1001231);
+}