expressions: Implement the REPLACE string function.

[pspp] / src / language / expressions / helpers.c

diff --git a/src/language/expressions/helpers.c b/src/language/expressions/helpers.c
index 85705098a2df44e2ad0e39da0764f75684bc9407..cfc46290b785cfad8c4d5dd8182c65fe016774cd 100644 (file)
--- a/src/language/expressions/helpers.c
+++ b/src/language/expressions/helpers.c
@@ -1,5 +1,5 @@
 /* PSPP - a program for statistical analysis.
-   Copyright (C) 2008 Free Software Foundation, Inc.
+   Copyright (C) 2008, 2010, 2011, 2015, 2016 Free Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -15,29 +15,19 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>. */
 
 #include <config.h>
-#include "helpers.h"
+
+#include "language/expressions/helpers.h"
+
 #include <gsl/gsl_roots.h>
 #include <gsl/gsl_sf.h>
-#include <libpspp/assertion.h>
-#include <libpspp/pool.h>
-#include "private.h"
-
-const struct substring empty_string = {NULL, 0};
 
-static void
-expr_error (void *aux UNUSED, const char *format, ...)
-{
-  struct msg m;
-  va_list args;
+#include "language/expressions/private.h"
+#include "libpspp/assertion.h"
+#include "libpspp/pool.h"
 
-  m.category = MSG_SYNTAX;
-  m.severity = MSG_ERROR;
-  va_start (args, format);
-  m.text = xvasprintf (format, args);
-  va_end (args);
+#include "gl/minmax.h"
 
-  msg_emit (&m);
-}
+const struct substring empty_string = {NULL, 0};
 
 double
 expr_ymd_to_ofs (double year, double month, double day)
@@ -45,6 +35,8 @@ expr_ymd_to_ofs (double year, double month, double day)
   int y = year;
   int m = month;
   int d = day;
+  char *error;
+  double ofs;
 
   if (y != year || m != month || d != day)
     {
@@ -53,7 +45,13 @@ expr_ymd_to_ofs (double year, double month, double day)
       return SYSMIS;
     }
 
-  return calendar_gregorian_to_offset (y, m, d, expr_error, NULL);
+  ofs = calendar_gregorian_to_offset (y, m, d, &error);
+  if (error != NULL)
+    {
+      msg (SE, "%s", error);
+      free (error);
+    }
+  return ofs;
 }
 
 double
@@ -179,10 +177,13 @@ recognize_unit (struct substring name, enum date_unit *unit)
         return true;
       }
 
-  msg (SE, _("Unrecognized date unit \"%.*s\".  "
-             "Valid date units are \"years\", \"quarters\", \"months\", "
-             "\"weeks\", \"days\", \"hours\", \"minutes\", and \"seconds\"."),
-       (int) ss_length (name), ss_data (name));
+  msg (SE, _("Unrecognized date unit `%.*s'.  "
+             "Valid date units are `%s', `%s', `%s', "
+             "`%s', `%s', `%s', `%s', and `%s'."),
+       (int) ss_length (name), ss_data (name),
+       "years", "quarters", "months",
+       "weeks", "days", "hours", "minutes", "seconds");
+
   return false;
 }
 
@@ -330,7 +331,7 @@ recognize_method (struct substring method_name, enum date_sum_method *method)
   else
     {
       msg (SE, _("Invalid DATESUM method.  "
-                 "Valid choices are \"closest\" and \"rollover\"."));
+                 "Valid choices are `%s' and `%s'."), "closest", "rollover");
       return false;
     }
 }
@@ -342,6 +343,7 @@ add_months (double date, int months, enum date_sum_method method)
 {
   int y, m, d, yd;
   double output;
+  char *error;
 
   calendar_offset_to_gregorian (date / DAY_S, &y, &m, &d, &yd);
   y += months / 12;
@@ -361,9 +363,14 @@ add_months (double date, int months, enum date_sum_method method)
   if (method == SUM_CLOSEST && d > calendar_days_in_month (y, m))
     d = calendar_days_in_month (y, m);
 
-  output = calendar_gregorian_to_offset (y, m, d, expr_error, NULL);
+  output = calendar_gregorian_to_offset (y, m, d, &error);
   if (output != SYSMIS)
     output = (output * DAY_S) + fmod (date, DAY_S);
+  else
+    {
+      msg (SE, "%s", error);
+      free (error);
+    }
   return output;
 }
 
@@ -404,7 +411,7 @@ expr_date_sum (double date, double quantity, struct substring unit_name,
 }
 
 int
-compare_string (const struct substring *a, const struct substring *b)
+compare_string_3way (const struct substring *a, const struct substring *b)
 {
   size_t i;
 
@@ -656,3 +663,57 @@ npdf_beta (double x, double a, double b, double lambda)
       return sum;
     }
 }
+
+double
+round_nearest (double x, double mult, double fuzzbits)
+{
+  double adjustment;
+
+  if (fuzzbits <= 0)
+    fuzzbits = settings_get_fuzzbits ();
+  adjustment = .5 + exp2 (fuzzbits - DBL_MANT_DIG);
+
+  x /= mult;
+  x = x >= 0. ? floor (x + adjustment) : -floor (-x + adjustment);
+  return x * mult;
+}
+
+struct substring
+replace_string (struct expression *e,
+                struct substring haystack,
+                struct substring needle,
+                struct substring replacement,
+                double n)
+{
+  if (!needle.length
+      || haystack.length < needle.length
+      || n <= 0
+      || n == SYSMIS)
+    return haystack;
+
+  struct substring result = alloc_string (e, MAX_STRING);
+  result.length = 0;
+
+  size_t i = 0;
+  while (i <= haystack.length - needle.length)
+    if (!memcmp (&haystack.string[i], needle.string, needle.length))
+      {
+        size_t copy_len = MIN (replacement.length, MAX_STRING - result.length);
+        memcpy (&result.string[result.length], replacement.string, copy_len);
+        result.length += copy_len;
+        i += needle.length;
+
+        if (--n < 1)
+          break;
+      }
+    else
+      {
+        if (result.length < MAX_STRING)
+          result.string[result.length++] = haystack.string[i];
+        i++;
+      }
+  while (i < haystack.length && result.length < MAX_STRING)
+    result.string[result.length++] = haystack.string[i++];
+
+  return result;
+}