ModSim ass3: Started working on test program.

modsim/ass3/Makefile

+CC=gcc
+CFLAGS=-Wall -Wextra -pedantic -std=c99 -D_GNU_SOURCE -g -O0
+LFLAGS=-lm
+
+all: test
+
+test: test.o methods.o
+	$(CC) $(CFLAGS) $(LFLAGS) -o $@ $^
+
+%.o: %.c
+	$(CC) $(CFLAGS) $(LFLAGS) -o $@ $^
+
+clean:
+	rm *.o test

modsim/ass3/diff.c

-#include <stdlib.h>
-#include <stdio.h>
-
-int main(void) {
-
-
-    return 0;
-}

modsim/ass3/func_ptr.h

-#ifndef FUNC_PTR_H
-#define FUNC_PTR_H
-
-typedef double (*func_ptr)(double t);
-typedef double (*diff_ptr)(double t, func_ptr y);
-
-#endif

modsim/ass3/methods.c

+#include <stdlib.h>
+#include <stdio.h>
+#include "methods.h"
+
+/*
+t0 – the start value t0 of t (input)
+t1 – the final value of t (input)
+dt – the increment in t (input)
+y0[N] – the values of the functions y_n(t) at t0 (input)
+y1[N] – the values of the functions y_n(t) at t1 (output)
+N – the dimension of y (input)
+int f(double t, double * y, double * dy, void * params) – computes
+the vector of derivatives dy[N] of y[N], given t, y[N] and params
+void * params – a pointer to a struct containing any parameters needed
+by f (input)
+All three functions return an estimate of y(t1) in y1.
+All functions return 0 upon success, or -1 when a computational error
+occurs (overflow, NaN or such)
+*/
+
+int Euler(double t0, double t1, double dt, double *y0, double *y1, int N,
+        f_ptr f, void *params) {
+    int i, steps = (int)((t1 - t0) / dt + .5);
+
+    for( i = 0; i < N; i++ ) {
+
+    }
+
+    return 0;
+}
+
+int RungeKutta2(double t0, double t1, double dt, double *y0, double *y1, int N,
+        f_ptr f, void *params) {
+
+    return 0;
+}
+
+int RungeKutta4(double t0, double t1, double dt, double *y0, double *y1, int N,
+        f_ptr f, void *params)
+
+    return 0;
+}

modsim/ass3/methods.h

+typedef int (*f_ptr)(double t, double *y, double *dy, void *params);
+
+int Euler(double t0, double t1, double dt, double *y0, double *y1, int N,
+    f_ptr f, void *params);
+
+int RungeKutta2(double t0, double t1, double dt, double *y0, double *y1, int N,
+    f_ptr f, void *params);
+
+int RungeKutta4(double t0, double t1, double dt, double *y0, double *y1, int N,
+    f_ptr f, void *params);

modsim/ass3/test.c

+#include <stdlib.h>
+#include <stdio.h>
+#include "methods.h"
+
+int f_test_1(double t, double *y, double *dy, void *params) {
+    *dy = 1.0;
+
+    return 1;
+}
+
+int f_test_2(double t, double *y, double *dy, void *params) {
+    double result = *y;
+
+    if( isnan(result) ) {
+        return -1;
+    } else {
+        *dy = result;
+        return 0;
+    }
+}
+
+int f_test_3(double t, double *y, double *dy, void *params) {
+    double result = *y * *y;
+
+    if( isnan(result) ) {
+        return -1;
+    } else {
+        *dy = result;
+        return 0;
+    }
+}
+
+int main(void) {
+
+
+    return 0;
+}