add the two library files that I thought I added last time

src/lib/math_common.c

@@ -0,0 +1,62 @@
+#include "pla.h"
+
+/* Relative error between two large numbers */
+#define FLOATVAL_EPSILON_REL 0.0001
+
+/* Absolute difference between two small numbers */
+#define FLOATVAL_EPSILON_ABS 0.00001
+
+/* Above we do relative error, below we use abs */
+#define FLOATVAL_REL_THRESHOLD 10
+
+/* Check if two floats are equalish. Above a certain threshold we want to do a
+   relative error calculation because precision between subsequent large
+   numbers can be much larger than standard epsilon values. Below the threshold
+   we want to do an absolute calculation because as the values approach zero the
+   error value quickly begins to diverge, even for very similar values. The
+   values for absolute difference, relative error, and threshold need to be
+   tuned. */
+INTVAL
+floats_are_equal(FLOATVAL a, FLOATVAL b)
+{
+    FLOATVAL diff = fabs(a - b);
+    if (a == b)
+        return 1;
+    if (diff > FLOATVAL_EPSILON_ABS)
+        return 0;
+    if (a > FLOATVAL_REL_THRESHOLD) {
+        FLOATVAL err = diff / b;
+        if (err > FLOATVAL_EPSILON_REL)
+            return 0;
+    }
+    return 1;
+}
+
+void
+get_complex_value_from_pmc(PARROT_INTERP, PMC * value, FLOATVAL * real,
+    FLOATVAL * imag)
+{
+    switch (value->vtable->base_type) {
+        case enum_class_String:
+            value = Parrot_pmc_new_init(interp, enum_class_Complex, value);
+        case enum_class_Complex:
+            *real = VTABLE_get_number_keyed_int(interp, value, 0);
+            *imag = VTABLE_get_number_keyed_int(interp, value, 1);
+            break;
+        case enum_class_Float:
+            *real = VTABLE_get_number(interp, value);
+            *imag = 0.0;
+            break;
+        case enum_class_Integer:
+            {
+                const INTVAL _r = VTABLE_get_integer(interp, value);
+                *real = (FLOATVAL)_r;
+            }
+            *imag = 0.0;
+            break;
+        default:
+            /* TODO: We should support HLL-mapped types here. */
+            Parrot_ex_throw_from_c_args(interp, NULL, EXCEPTION_OUT_OF_BOUNDS,
+                "PLA: cannot set unknown PMC type");
+    }
+}

src/lib/matrix_common.c

@@ -0,0 +1,20 @@
+#include "pla.h"
+
+void
+intkey_to_coords(PARROT_INTERP, const INTVAL rows, const INTVAL cols,
+    const INTVAL key, INTVAL * row, INTVAL * col)
+{
+    if (rows == 0) {
+        Parrot_ex_throw_from_c_args(interp, NULL, EXCEPTION_OUT_OF_BOUNDS,
+            "PLA: Index out of bounds.");
+    } else {
+        const INTVAL r = key / rows;
+        const INTVAL c = key % rows;
+        if (key < 0 || r > rows || c > cols) {
+            Parrot_ex_throw_from_c_args(interp, NULL, EXCEPTION_OUT_OF_BOUNDS,
+                "PLA: Index out of bounds.");
+        }
+        *row = r;
+        *col = c;
+    }
+}