utfile

README.md

@@ -13,8 +13,18 @@ which will place a binary at `build/nstrophy`.
 
 The syntax for the execution of Nstrophy is
 ```bash
-./build/nstrophy [-p parameters] [-s savefile] <command>
+./build/nstrophy [-p parameters] [-s savefile] [-u u_outfile] <command>
 ```
+* `parameters` is a list of parameters for the computation, see
+  [Parameters](#parameters)
+
+* `savefile` is a file where the last step of the computation is saved in
+  binary format so that the computation can be resumed after it has terminated,
+  see
+  [Interrupting and resuming the computation](#interrupting-and-resuming-the-computation).
+
+* `u_outfile` is a file to which the final u is written in plain text format,
+  which can be used as an initial condition for a future computation.
 
 Nstrophy is written in C. The Makefile uses the GNU C Compiler.
 
@@ -114,7 +124,7 @@ should be a `;` sperated list of `key=value` pairs. The possible keys are
   norm.
 
 
-# Interrupting/resuming the computation
+# Interrupting and resuming the computation
 
 The computation can be interrupted by sending Nstrophy the `SIGINT` signal
 (e.g. by pressing `Ctrl-C`.) When Nstrophy receives the `SIGINT` signal, it

src/main.c

@@ -60,7 +60,7 @@ int print_usage();
 int print_params(nstrophy_parameters parameters, char* initfile_str, char* drivingfile_str, FILE* file);
 
 // read command line arguments
-int read_args(int argc, const char* argv[], char** params, unsigned int* command, unsigned int* nthreads, char** savefile_str);
+int read_args(int argc, const char* argv[], char** params, unsigned int* command, unsigned int* nthreads, char** savefile_str, char** utfile_str);
 int read_params(char* param_str, nstrophy_parameters* parameters, char** initfile_str, char** drivingfile_str);
 int set_parameter(char* lhs, char* rhs, nstrophy_parameters* parameters, bool* setN1, bool* setN2, char** initfile_str, char** drivingfile_str);
 
@@ -94,14 +94,16 @@ int main (
   _Complex double* u0;
   _Complex double *g;
   char* savefile_str=NULL;
+  char* utfile_str=NULL;
   char* initfile_str=NULL;
   char* drivingfile_str=NULL;
   FILE* savefile=NULL;
+  FILE* utfile=NULL;
 
   command=0;
 
   // read command line arguments
-  ret=read_args(argc, argv, &param_str, &command, &nthreads, &savefile_str);
+  ret=read_args(argc, argv, &param_str, &command, &nthreads, &savefile_str, &utfile_str);
   if(ret<0){
     return(-1);
   }
@@ -152,6 +154,15 @@ int main (
     }
   }
 
+  // open utfile (do this after closing init file)
+  if(utfile_str!=NULL){
+    utfile=fopen(utfile_str,"w");
+    if(utfile==NULL){
+      fprintf(stderr,"Error opening file '%s' for writing: %s\n", utfile_str, strerror(errno));
+      return(-1);
+    }
+  }
+
   // print parameters
   print_params(parameters, initfile_str, drivingfile_str, stderr);
   print_params(parameters, initfile_str, drivingfile_str, stdout);
@@ -173,7 +184,7 @@ int main (
     // register signal handler to handle aborts
     signal(SIGINT, sig_handler);
     signal(SIGTERM, sig_handler);
-    enstrophy(parameters.K1, parameters.K2, parameters.N1, parameters.N2, parameters.final_time, parameters.nu, parameters.delta, parameters.L, parameters.adaptive_tolerance, parameters.adaptive_factor, parameters.max_delta, parameters.adaptive_norm, u0, g, parameters.irreversible, parameters.algorithm, parameters.print_freq, parameters.starting_time, nthreads, savefile, (char*)argv[0], param_str, savefile_str);
+    enstrophy(parameters.K1, parameters.K2, parameters.N1, parameters.N2, parameters.final_time, parameters.nu, parameters.delta, parameters.L, parameters.adaptive_tolerance, parameters.adaptive_factor, parameters.max_delta, parameters.adaptive_norm, u0, g, parameters.irreversible, parameters.algorithm, parameters.print_freq, parameters.starting_time, nthreads, savefile, utfile, (char*)argv[0], param_str, savefile_str);
   }
   else if(command==COMMAND_QUIET){
     quiet(parameters.K1, parameters.K2, parameters.N1, parameters.N2, parameters.final_time, parameters.nu, parameters.delta, parameters.L, parameters.adaptive_tolerance, parameters.adaptive_factor, parameters.max_delta, parameters.adaptive_norm, parameters.starting_time, u0, g, parameters.irreversible, parameters.algorithm, nthreads, savefile);
@@ -191,12 +202,17 @@ int main (
     fclose(savefile);
   }
 
+  // close utfile
+  if (utfile!=NULL){
+    fclose(utfile);
+  }
+
   return(0);
 }
 
 // usage message
 int print_usage(){
-  fprintf(stderr, "usage:\n       nstrophy [-t nthreads] [-p parameters] [-s savefile] <command>\n\n");
+  fprintf(stderr, "usage:\n       nstrophy [-t nthreads] [-p parameters] [-s savefile] [-u u_outfile] <command>\n\n");
   return(0);
 }
 
@@ -301,13 +317,15 @@ int print_params(
 #define CP_FLAG_PARAMS 1
 #define CP_FLAG_NTHREADS 2
 #define CP_FLAG_SAVEFILE 3
+#define CP_FLAG_UTFILE 4
 int read_args(
   int argc,
   const char* argv[],
   char** params,
   unsigned int* command,
   unsigned int* nthreads,
-  char** savefile_str
+  char** savefile_str,
+  char** utfile_str
 ){
   int i;
   int ret;
@@ -331,6 +349,9 @@ int read_args(
 	case 's':
 	  flag=CP_FLAG_SAVEFILE;
 	  break;
+	case 'u':
+	  flag=CP_FLAG_UTFILE;
+	  break;
 	default:
 	  fprintf(stderr, "unrecognized option '-%c'\n", *ptr);
 	  print_usage();
@@ -358,6 +379,11 @@ int read_args(
       *savefile_str=(char*)argv[i];
       flag=0;
     }
+    // savefile
+    else if(flag==CP_FLAG_UTFILE){
+      *utfile_str=(char*)argv[i];
+      flag=0;
+    }
     // computation to run
     else{
       if(strcmp(argv[i], "uk")==0){

src/navier-stokes.c

@@ -126,6 +126,7 @@ int uk(
     }
   }
 
+  // TODO: update handling of savefile
   // save final entry to savefile
   write_vec_bin(u, K1, K2, savefile);
 
@@ -155,6 +156,7 @@ int enstrophy(
   double starting_time,
   unsigned int nthreads,
   FILE* savefile,
+  FILE* utfile,
   // for interrupt recovery
   char* cmd_string,
   char* params_string,
@@ -307,6 +309,11 @@ int enstrophy(
     }
   }
 
+  // save final u to utfile in txt format
+  if(utfile!=NULL){
+    write_vec(u, K1, K2, utfile);
+  }
+
   ns_free_tmps(u, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7, fft1, fft2, ifft, algorithm);
   return(0);
 }
@@ -378,6 +385,7 @@ int quiet(
     step=next_step;
   }
 
+  // TODO: update handling of savefile
   // save final entry to savefile
   write_vec(u, K1, K2, savefile);
 

src/navier-stokes.h

@@ -36,7 +36,7 @@ typedef struct fft_vects {
 int uk( int K1, int K2, int N1, int N2, double final_time, double nu, double delta, double L, double adaptive_tolerance, double adaptive_factor, double max_delta, unsigned int adaptive_norm, _Complex double* u0, _Complex double* g, bool irreversible, unsigned int algorithm, double print_freq, double starting_time, unsigned int nthreadsl, FILE* savefile);
 
 // compute enstrophy and alpha
-int enstrophy( int K1, int K2, int N1, int N2, double final_time, double nu, double delta, double L, double adaptive_tolerance, double adaptive_factor, double max_delta, unsigned int adaptive_norm, _Complex double* u0, _Complex double* g, bool irreversible, unsigned int algorithm, double print_freq, double starting_time, unsigned int nthreads, FILE* savefile, char* cmd_string, char* params_string, char* savefile_string);
+int enstrophy( int K1, int K2, int N1, int N2, double final_time, double nu, double delta, double L, double adaptive_tolerance, double adaptive_factor, double max_delta, unsigned int adaptive_norm, _Complex double* u0, _Complex double* g, bool irreversible, unsigned int algorithm, double print_freq, double starting_time, unsigned int nthreads, FILE* savefile, FILE* utfile, char* cmd_string, char* params_string, char* savefile_string);
 
 // compute solution as a function of time, but do not print anything (useful for debugging)
 int quiet( int K1, int K2, int N1, int N2, double final_time, double nu, double delta, double L, double adaptive_tolerance, double adaptive_factor, double max_delta, unsigned int adaptive_norm, double starting_time, _Complex double* u0, _Complex double* g, bool irreversible, unsigned int algorithm, unsigned int nthreads, FILE* savefile);