Implementation of Map Function(s) in C

application.c

@@ -0,0 +1,72 @@
+#include <stdio.h>
+#include "map.h"
+
+/* DESCRIPTION
+ * Since C does not (at least easily) allow a way to pass arguments of an arbitrary
+ * type to a function, I decided that the simplest course of action was to split
+ * the map function into three separate map functions, each corresponding to a different
+ * type. Each function is identical in implementation, and only differs in the type
+ * of data it is able to manipulate. Each map function takes a function, applies
+ * it to each element of an array of input data, and then stores the results in
+ * an output array that is big enough to hold each result.
+ *
+ * PARAMETERS
+ * type (*function)(type): Pointer to a function that takes an argument of a particular
+ *                         type and returns a value of that same type.
+ *
+ * type* source_iterable:  Pointer to an array of values of a particular type that
+ *                         will each be passed to the aforementioned function.
+ *
+ * type* dest_iterable:    Pointer to an array of values of a particular type that
+ *                         will hold the results of applying the aforementioned
+ *                         function to each of the values stored in source_iterable.
+ *
+ * size_t length:          Number of values to perform the operation on. Must be
+ *                         less than or equal to the length of the shorter of the
+ *                         two arrays.
+ *
+ * RETURN VALUE
+ * Each function will return -1 if the operation was unsuccessful, otherwise it
+ * will return 0.
+ */
+int map_int(int (*function)(int), int* source_iterable, int* dest_iterable, size_t length)
+{
+    if (length < 1) {
+        fprintf(stderr, "Length must be positive.\n");
+        return -1;
+    }
+
+    for (int i = 0; i < length; ++i)
+    {
+        dest_iterable[i] = function(source_iterable[i]);
+    }
+    return 0;
+}
+
+int map_char(char (*function)(char), char* source_iterable, char* dest_iterable, size_t length)
+{
+    if (length < 1) {
+        fprintf(stderr, "Length must be positive.\n");
+        return -1;
+    }
+
+    for (int i = 0; i < length; ++i)
+    {
+        dest_iterable[i] = function(source_iterable[i]);
+    }
+    return 0;
+}
+
+int map_float(float (*function)(float), float* source_iterable, float* dest_iterable, size_t length)
+{
+    if (length < 1) {
+        fprintf(stderr, "Length must be positive.\n");
+        return -1;
+    }
+
+    for (int i = 0; i < length; ++i)
+    {
+        dest_iterable[i] = function(source_iterable[i]);
+    }
+    return 0;
+}