07_Raster_scripting.ipynb

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 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "In this quick notebook we will use some functions of the scripting library to work with raster maps"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "from grass import script"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "MAP = 'elevation'\n",
    "POINT = [[640000, 228000]]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Information"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Obtain information about the map"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "eleinfo = script.raster_info(MAP)\n",
    "print(eleinfo)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Or query the map on a point"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "script.raster_what(MAP, POINT)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Map algebra"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "We can execute any kind of *map algebra analysis* using an interface to <a href=\"http://grass.osgeo.org/grass70/manuals/r.mapcalc.html\" target=\"_blank\">r.mapcalc</a> module"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "script.mapcalc(\"elevation100 = if(elevation > 100, elevation, null())\", overwrite=True)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Now check the result: the maximum should be the same of original map and the minimum should be 100"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "newinfo = script.raster_info(\"elevation100\")\n",
    "if eleinfo['max'] == newinfo['max'] and newinfo['min'] == 100:\n",
    "    print(\"Succeded\")\n",
    "else:\n",
    "    print(\"Failed\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Other modules"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Is it possible to run all the modules with the following functions"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "from grass.pygrass.utils import looking\n",
    "\n",
    "looking(script, '*command*')"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "**You can see some examples of these functions in the Modules notebook**.\n",
    "\n",
    "Read more about about these functions on the <a href=\"http://grass.osgeo.org/grass71/manuals/libpython/script.html#module-script.core\" target=\"_blank\">classes documentations</a> or in the <a href=\"http://grasswiki.osgeo.org/wiki/Python#Python_Scripting_Library\" target=\"_blank\">wiki page</a>"
   ]
  }
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