Change format for grouping constants

Instead of grouping contstants by reference, define
broader groups: mathematical, universal_physical, earth_physical,
solar, water.  This allows constants in each group to be from different references.

Move all references to a section at top and then add as key in each
constant.

Author: rljacob

pcd.yaml

@@ -1,25 +1,55 @@
 physical_constants_dictionary:
-  version_number: 0.0.0
-  institution: National ESPC/NUOPC
+  version_number: 0.0.1
+  institution: ICAMS
   description: Community-based dictionary for consistent physical constant sets
-  contact: National ESPC
+  contact: ICAMS
+
+  references:
+    ASHandbook1964:
+      description: "Standard reference for mathematical functions and constants"
+      citation: "
+        Abramowitz, A., and Stegun, I.A., Handbook of Mathematical Functions
+        With Formulas, Graphs, and Mathematical Tables, DOC/National Bureau of Standards,
+        Applied Mathematics Series, 55, June 1964.
+      "
+    CODATA2014:
+      description: "CODATA 2014 recommended values of fundamental physical constants"
+      citation: "
+        Mohr, P.J., Newell, D.B., and Taylor, B.N., J. Phys. Chem. Ref. Data 45,
+        043102 (2016); doi: 10.1063/1.4954402
+      "
+    moritz_2000:
+      description: "Geodetic Reference System 1980 for Earth's physical parameters"
+      citation: "
+        Moritz, H, Geodetic Reference System 1980. J. Geodesy, 74 128-133, 2000.
+      "
+    kopp_2005:
+      description: "Total solar irradiance measurements from SORCE TIM instrument"
+      citation: "
+        Kopp, G., Lawrence, G., and Rottman, G., The Total Irradiance Monitor (TIM):
+        Science results, Sol. Phys., 230, 129–139, 2005. doi:10.1007/s11207-005-7433-9.
+      "
+    wagner_2002:
+      description: "IAPWS-95 formulation for thermodynamic properties of water"
+      citation: "
+        Wagner, W., and Pruss, A., The IAPWS Formulation 1995 for the Thermodynamic
+        Properties of Ordinary Water Substance for General and Scientific Use,
+        J. Phys. Chem. Ref. Data, 31, 387-535, 2002.
+      "
+
   set:
-    - ASHandbook1964:
+    - mathematical:
         description: "
           Common mathematical constants.
         "
-        citation: "
-          Abramowitz, A., and Stegun, I.A., Handbook of Mathematical Functions
-          With Formulas, Graphs, and Mathematical Tables, DOC/National Bureau of Standards,
-          Applied Mathematics Series, 55, June 1964.
-        "
         entries:
           - name: pi
             value: 3.141592653589793238462643
             units: none
             prec: double
             type: strict
             uncertainty: exact
+            citation: ASHandbook1964
             description: "
               Ratio of a circle's circumference to its diameter.
             "
@@ -29,15 +59,17 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: ASHandbook1964
             description: "
               Base of natural logarithms.
             "
-          - name: gamma
+          - name: em_gamma
             value: 0.577215664901532860606512
             units: none
             prec: double
             type: strict
             uncertainty: exact
+            citation: ASHandbook1964
             description: "
               Euler-Mascheroni constant.
             "
@@ -47,6 +79,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: ASHandbook1964
             description: "
               Radian to degrees conversion factor.
             "
@@ -56,6 +89,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: ASHandbook1964
             description: "
               Degree to radiant conversion factor.
             "
@@ -65,6 +99,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: ASHandbook1964
             description: "
               Square root of 2.
             "
@@ -74,16 +109,13 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: ASHandbook1964
             description: "
               Square root of 3.
             "
-    - CODATA2014:
+    - universal_physical:
         description: "
-          CODATA Recommended Values of the Fundamental Physical Constants: 2014
-        "
-        citation: "
-          Mohr, P.J., Newell, D.B., and Taylor, B.N., J. Phys. Chem. Ref. Data 45,
-          043102 (2016); doi: 10.1063/1.4954402
+          Fundamental Physical Constants
         "
         entries:
           - name: speed_of_light_in_vacuum
@@ -92,6 +124,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: CODATA2014
             description: "
               The speed at which light propagates in vacuum.
               Albert Einstein postulated that the speed of light with respect to
@@ -103,6 +136,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             relative_uncertainty: 4.7E-05
+            citation: CODATA2014
             description: "
               Empirical constant used to calculate the attractive force between
               two bodies according to Newton's law of universal gravitation.
@@ -113,6 +147,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: CODATA2014
             description: "
               Nominal acceleration of an object in a vacuum at sea level at a
               geodetic latitude of 45 degrees.
@@ -123,6 +158,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: CODATA2014
             description: "
               Unit of pressure equivalent to 760 mmHg (torr), 29.92 inches Hg and 14.696 psi.
             "
@@ -132,6 +168,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             relative_uncertainty: 1.2E-08
+            citation: CODATA2014
             description: "
               Number of particles (atoms, molecules) in one mole.
             "
@@ -141,6 +178,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             relative_uncertainty: 5.7E-07
+            citation: CODATA2014
             description: "
               Proportionality constant between the average kinetic energy
               of particles in a gas and its temperature.
@@ -151,6 +189,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             relative_uncertainty: 2.3E-06
+            citation: CODATA2014
             description: "
               Proportionality constant between the power emitted by
               a black body and the fourth power of its temperature, 
@@ -162,6 +201,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             relative_uncertainty: 5.7E-07
+            citation: CODATA2014
             description: "
               Gas constant used in the ideal gas law. It is equivalent to
               Boltzmann's constant espressed in J mol-1 K-1.
@@ -172,16 +212,14 @@ physical_constants_dictionary:
             prec: double
             type: strict
             relative_uncertainty: 5.7E-07
+            citation: CODATA2014
             description: "
               Ideal gas molar volume as computed by the ideal gas law (RT/p)
               at Standard Temperature and Pressure (STP: 273.15K, 100 kPa).
             "
-    - GRS80:
+    - earth_physical:
         description: "
-          Geodetic Reference System 1980.
-        "
-        citation: "
-          Moritz, H, Geodetic Reference System 1980. J. Geodesy, 74 128-133, 2000.
+          Properties of the planet Earth
         "
         entries:
           - name: geocentric_gravitational_constant
@@ -190,6 +228,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: moritz_2000
             description: "
               Product (GM) of the mass of the Earth (M) and the universal gravitational
               constant (G).
@@ -200,6 +239,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: moritz_2000
             description: "
               The semi-major axis of Earth's reference ellipsoid.
             "
@@ -209,6 +249,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: moritz_2000
             description: "
               Mechanical ellipticity of Earth.
             "
@@ -218,6 +259,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: moritz_2000
             description: "
               Angular velocity of Earth's rotation.
             "
@@ -227,6 +269,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: moritz_2000
             description: "
               The semi-major axis of Earth's reference ellipsoid.
               Derived constant.
@@ -237,6 +280,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: moritz_2000
             description: "
               Defined as f = (semimajor_axis - semiminor_axis) / semimajor_axis.
               Derived constant.
@@ -247,6 +291,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: moritz_2000
             description: "
               Defined as 1/f. Derived constant.
             "
@@ -256,6 +301,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: moritz_2000
             description: "
               Derived constant. Equal to (2 semimajor_axis + semiminor_axis) / 3.
             "
@@ -265,6 +311,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: moritz_2000
             description: "
               Radius of Earth's reference sphere with same surface as ellipsoid's.
               Derived constant
@@ -275,18 +322,14 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: moritz_2000
             description: "
               Radius of Earth's reference sphere with same volume as ellipsoid's.
               Derived constant.
             "
-    - SORCETIM2008:
+    - solar:
         description: "
-          NASA Solar Radiation and Climate Experiment (SORCE), Total Irradiance
-          Monitor (TIM)
-        "
-        citation: "
-          Kopp, G., Lawrence, G., and Rottman, G., The Total Irradiance Monitor (TIM):
-          Science results, Sol. Phys., 230, 129–139, 2005. doi:10.1007/s11207-005-7433-9.
+          Properties of the Sun
         "
         entries:
           - name: total_solar_irradiance
@@ -295,19 +338,14 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: 0.5
+            citation: kopp_2005
             description: "
               Most probable value of total solar irradiance representative of
               solar minimum (aka solar constant).
             "
-    - IAPWS1995:
+    - water:
         description: "
-          International Association for the Properties of Water and Steam (IAPWS).
-          Thermodynamic Property Formulations 1995 (http://www.iapws.org)
-        "
-        citation: "
-          Wagner, W., and Pruss, A., The IAPWS Formulation 1995 for the Thermodynamic 
-          Properties of Ordinary Water Substance for General and Scientific Use,
-          J. Phys. Chem. Ref. Data, 31, 387-535, 2002. 
+          Properties of pure water
         "
         entries:
           - name: water_molar_mass
@@ -316,6 +354,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: wagner_2002
             description: "
               Molar mass of H2O.
             "
@@ -325,6 +364,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: wagner_2002
             description: "
               Specific gas constant for water vapor.
             "
@@ -334,6 +374,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: wagner_2002
             description: "
               Triple point temperature of H2O.
             "
@@ -343,6 +384,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: wagner_2002
             description: "
               Triple point pressure of H2O.
               Calculated from Eq. (6.4).
@@ -353,6 +395,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: wagner_2002
             description: "
               Triple point density of liquid H2O.
               Calculated from Eq. (6.4).
@@ -363,6 +406,7 @@ physical_constants_dictionary:
             prec: double
             type: strict
             uncertainty: exact
+            citation: wagner_2002
             description: "
               Triple point density of vapor H2O.
               Calculated from Eq. (6.4).