added a method for writing an XDI file

Author: bruceravel

README.md

@@ -11,7 +11,7 @@ files containing single-scan XAS data.
 
 
 **This is a work in progress.  Version 1.0 of the XDI specification has
-not yet been released.**
+not yet been declared done.**
 
 
 Specification Documents
@@ -27,21 +27,23 @@ Implementations
 ---------------
 
 Implementations are found in directories named according to the
-programming language.  At this time, we provide
+programming language.  The main C library is in `lib/`, all others are
+under `languages`.
 
- * C (written by Matt Newville with input from Bruce Ravel)
+At this time, we provide
+
+ * C (written by Matt Newville and Bruce Ravel)
  * Python (written by Matt Newville)
  * Perl (written by Bruce Ravel)
  * Fortran 77 (written by Matt Newville)
 
 We encourage the contribution of new language implementations,
-especially:
+such as:
 
  * Matlab
  * IDL
  * LabView
- * C++
- * Fortran 95
+ * Fortran 95 or later
  * Java
 
 and any other language that gets used by XAS practitioners.
@@ -52,6 +54,24 @@ community.  Unit testing is strongly encouraged.  So is complete
 documentation of the building, installation, and use of the language
 package.
 
+Build
+-----
+
+cd into the `lib/` directory and do:
+
+	~> ./configure
+	~> make
+	~> sudo make install
+
+This will install static and dynamic libraries to `/usr/local/lib` and
+header files to `/usr/local/include`.
+
+Obviously, you will need a C compiler.
+
+To build the language specific interfaces, cd to the folder under
+`languages/` and follow the build instructions there.
+
+
 Other files
 -----------
 
@@ -69,4 +89,4 @@ Other files
 		data/co_metal_rt.xdi: XAS Data Interchange file -- XDI specification 1.0
 
    It also defines an icon and a registry entry for XDI files on
-   Windows.
+   Windows.  (The Windows reg entry does not currently work)

lib/README.md

@@ -120,6 +120,7 @@ condition of the most recently performed action.  The relation between
 the returned error/warning codes and the error messages are tabulated
 below.
 
+To export data as a valid XDI file, use `XDI_writefile`.
 
 
 ### Read an XDI file
@@ -255,6 +256,14 @@ The return value is 0 if an array with that index is in the data
 table.  That is, the index argument must be smaller than the `narrays`
 attribute. The return value is -1 if the array cannot be retrieved.
 
+### Write an XDI file
+
+Write an XDI file from the  content of the XDIFile struct.
+
+```C
+	XDI_writefile(xdifile, "outfile.xdi");
+```
+
 ### Destroy and deallocate the XDIFile struct
 
 To deallocate the memory from the XDIFile struct, do this:

lib/writetest.c

@@ -0,0 +1,29 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include "strutil.h"
+#include "xdifile.h"
+
+
+void show_syntax(void) {
+  /* show command line syntax */
+  printf("\nSyntax: writetest infile outfile\n");
+}
+
+int main(int argc, char **argv) {
+  XDIFile *xdifile;
+  long ret, i;
+
+  /* require 2 arguments! */
+  if (argc < 3) {
+    show_syntax();
+    return 1;
+  }
+
+
+  /* read xdifile */
+  xdifile = malloc(sizeof(XDIFile));
+  ret = XDI_readfile(argv[1], xdifile);
+  XDI_writefile(xdifile, argv[2]);
+}

lib/xdifile.c

@@ -570,6 +570,66 @@ XDI_readfile(char *filename, XDIFile *xdifile) {
 
 }
 
+_EXPORT(void)
+XDI_writefile(XDIFile *xdifile, char *filename) {
+  int i, j, count;
+
+  char quote[1025];
+  const char s[2] = "\n";
+  char *token;
+
+  int regex_status;
+  struct slre_cap caps[3];
+
+  FILE *fp;
+  fp = fopen(filename, "w");
+  
+  /* version line */
+  strcpy(quote, xdifile->comments);
+  fprintf(fp, "# XDI/%s %s\n", xdifile->xdi_version, xdifile->extra_version);
+
+  /* metadata section */
+  for (i=0; i < xdifile->nmetadata; i++) {
+        fprintf(fp, "# %s.%s: %s\n",
+		xdifile->meta_families[i],
+		xdifile->meta_keywords[i],
+		xdifile->meta_values[i]);
+  }
+
+  /* user comments */
+  fprintf(fp, "#////////////////////////\n");
+  count = 0;
+  token = strtok(quote, s);   /* get the first token */
+  while( token != NULL ) {    /* walk through other tokens, skipping empty */
+    if (count == 0) {	      /* take care with empty first token */
+      regex_status = slre_match("^\\s*$", token, strlen(token), caps, 2, 0);
+      if (regex_status < 0) {
+	fprintf(fp, "#%s\n", token );
+      }
+    } else {
+      fprintf(fp, "#%s\n", token );
+    }
+    ++count;
+    token = strtok(NULL, s);
+  }
+  fprintf(fp, "#------------------------\n");
+
+  /* column labels */
+  fprintf(fp, "# ");
+  for (i = 0; i < xdifile->narrays; i++) {
+    fprintf(fp, " %s  ", xdifile->array_labels[i]);
+  }
+  fprintf(fp, "\n");
+  
+  /* data table */
+  for (i = 0; i < xdifile->npts; i++ ) {
+    for (j = 0; j < xdifile->narrays; j++ ) {
+      fprintf(fp, "  %-12.8g", xdifile->array[j][i]);
+    }
+    fprintf(fp, "\n");
+  }
+  
+}
 
 /* ============================================================================ */
 /* array management section                                                     */

lib/xdifile.h

@@ -59,6 +59,7 @@ typedef struct {
 } XDIFile;
 
 _EXPORT(int)  XDI_readfile(char *filename, XDIFile *xdifile) ;
+_EXPORT(void) XDI_writefile(XDIFile *xdifile, char *filename) ;
 _EXPORT(int)  XDI_get_array_index(XDIFile *xdifile, long n, double *out);
 _EXPORT(int)  XDI_get_array_name(XDIFile *xdifile, char *name, double *out);
 _EXPORT(int)  XDI_required_metadata(XDIFile *xdifile);