Demo

eq3.ipynb

eq_3.ipynb

test.py

import essm

class eq_test(essm.equations.Equation):
    expr = 1 == 1

vardef.ipynb

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{
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   "metadata": {},
   "outputs": [],
   "source": [
    "# Import standard variables from physics module\n",
    "from essm.variables.physics.thermodynamics import lambda_E, c_pa\n",
    "\n",
    "# Define custom variables\n",
    "class E_w(Variable):\n",
    "    \"\"\"Wet surface evaporation\n",
    "    (E in Priestley and Taylor, 1972))\n",
    "    \"\"\"\n",
    "    unit = kilogram/meter^2/second\n",
    "    latex_name = 'E'\n",
    "    \n",
    "class H_w(Variable):\n",
    "    \"\"\"Wet surface sensible heat flux (positive outwards)\"\"\"\n",
    "    unit = joule/second/meter^2\n",
    "    latex_name = 'H'\n",
    "      \n",
    "class q_a(Variable):\n",
    "    \"\"\"Specific humidity\"\"\"\n",
    "    unit = kilogram/meter^3\n",
    "    \n",
    "class q_s(Variable):\n",
    "    \"\"\"Specific humidity at saturation\"\"\"\n",
    "    unit = kilogram/meter^3\n",
    "    \n",
    "class s_PT(Variable):\n",
    "    \"\"\"Priestley-Taylor $\\partial q_s/\\partial T$\"\"\"\n",
    "    unit = kilogram/meter^3/kelvin\n",
    "    latex_name = 's'\n",
    "    \n",
    "class T(Variable):\n",
    "    \"\"\"Temperature\"\"\"\n",
    "    unit = kelvin\n",
    "\n",
    "# Re-define `lambda_E` as `L_E` to have the same latex representation as in the paper\n",
    "class L_E(lambda_E.definition):\n",
    "    \"\"\"Latent heat\"\"\"   \n",
    "    latex_name = 'L'\n",
    "    default = lambda_E.definition.default\n",
    "    unit = lambda_E.definition.unit\n",
    "    \n",
    "# Define `gamma_PT = c_pa/L_E` as in the paper\n",
    "class gamma_PT(Variable):\n",
    "    \"\"\"Priestley-Taylor $\\gamma$\"\"\"\n",
    "    expr = c_pa/L_E\n",
    "    latex_name = r'\\gamma'"
   ]
  }
  ],
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      "display_name": "SageMath 7.6",
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      "name": "sagemath"
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        "name": "ipython",
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      "nbconvert_exporter": "python",
      "pygments_lexer": "ipython2",
      "version": "2.7.13"
    },
    "nav_menu": {},
    "toc": {
      "navigate_menu": true,
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      "toc_section_display": "block",
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  },
  "nbformat": 4,
  "nbformat_minor": 2
}

variables.ipynb