Changes in data/endf.c from PullRequest Inc. review

openmc/data/endf.c

@@ -1,14 +1,31 @@
 #include <stdlib.h>
 
+//! Convert string representation of a floating point number into a double
+//
+//! This function handles converting floating point numbers from an ENDF 11
+//! character field into a double, covering all the corner cases. Floating point
+//! numbers are allowed to contain whitespace (which is ignored). Also, in
+//! exponential notation, it allows the 'e' to be omitted. A field containing
+//! only whitespace is to be interpreted as a zero.
+//
+//! \param buffer character input from an ENDF file
+//! \param n Length of character input
+//! \return Floating point number
+
 double cfloat_endf(const char* buffer, int n)
 {
   char arr[12]; // 11 characters plus a null terminator
   int j = 0; // current position in arr
   int found_significand = 0;
   int found_exponent = 0;
+
+  // limit n to 11 characters
+  n = n > 11 ? 11 : n;
+
   for (int i = 0; i < n; ++i) {
-    // Skip whitespace characters
     char c = buffer[i];
+
+    // Skip whitespace characters
     if (c == ' ') continue;
 
     if (found_significand) {

openmc/data/kalbach_mann.py

@@ -245,6 +245,7 @@ class KalbachMann(AngleEnergy):
                 eout_i = Mixture([p_discrete, 1. - p_discrete],
                                  [eout_discrete, eout_continuous])
 
+            # Precompound factor and slope are on rows 3 and 4, respectively
             km_r = Tabulated1D(data[0, j:j+n], data[3, j:j+n])
             km_a = Tabulated1D(data[0, j:j+n], data[4, j:j+n])
 

tests/unit_tests/test_endf.py

@@ -22,6 +22,7 @@ def test_float_endf():
     assert endf.float_endf('1.+2') == approx(100.0)
     assert endf.float_endf('-1.+2') == approx(-100.0)
     assert endf.float_endf('        ') == 0.0
+    assert endf.float_endf('9.876540000000000') == approx(9.87654)
 
 
 def test_int_endf():