| 1 | """ |
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| 2 | |
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| 3 | """ |
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| 4 | |
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| 5 | |
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| 6 | #FIXME: Ensure that all attributes of a georef are treated everywhere |
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| 7 | #and unit test |
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| 8 | |
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| 9 | import types, sys |
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| 10 | import copy |
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| 11 | |
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| 12 | from anuga.utilities.numerical_tools import ensure_numeric |
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| 13 | from anuga.anuga_exceptions import ANUGAError, TitleError, \ |
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| 14 | ParsingError, ShapeError |
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| 15 | from anuga.config import netcdf_float, netcdf_int, netcdf_float32 |
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| 16 | import anuga.utilities.log as log |
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| 17 | |
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| 18 | import numpy as num |
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| 19 | |
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| 20 | |
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| 21 | DEFAULT_ZONE = -1 |
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| 22 | TITLE = '#geo reference' + "\n" # this title is referred to in the test format |
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| 23 | |
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| 24 | DEFAULT_PROJECTION = 'UTM' |
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| 25 | DEFAULT_DATUM = 'wgs84' |
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| 26 | DEFAULT_UNITS = 'm' |
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| 27 | DEFAULT_FALSE_EASTING = 500000 |
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| 28 | DEFAULT_FALSE_NORTHING = 10000000 # Default for southern hemisphere |
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| 29 | |
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| 30 | |
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| 31 | ## |
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| 32 | # @brief A class for ... |
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| 33 | class Geo_reference: |
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| 34 | """ |
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| 35 | Attributes of the Geo_reference class: |
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| 36 | .zone The UTM zone (default is -1) |
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| 37 | .false_easting ?? |
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| 38 | .false_northing ?? |
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| 39 | .datum The Datum used (default is wgs84) |
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| 40 | .projection The projection used (default is 'UTM') |
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| 41 | .units The units of measure used (default metres) |
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| 42 | .xllcorner The X coord of origin (default is 0.0 wrt UTM grid) |
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| 43 | .yllcorner The y coord of origin (default is 0.0 wrt UTM grid) |
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| 44 | .is_absolute ?? |
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| 45 | |
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| 46 | """ |
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| 47 | |
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| 48 | ## |
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| 49 | # @brief Instantiate an instance of class Geo_reference. |
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| 50 | # @param zone The UTM zone. |
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| 51 | # @param xllcorner X coord of origin of georef. |
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| 52 | # @param yllcorner Y coord of origin of georef. |
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| 53 | # @param datum ?? |
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| 54 | # @param projection The projection used (default UTM). |
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| 55 | # @param units Units used in measuring distance (default m). |
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| 56 | # @param false_easting ?? |
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| 57 | # @param false_northing ?? |
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| 58 | # @param NetCDFObject NetCDF file *handle* to write to. |
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| 59 | # @param ASCIIFile ASCII text file *handle* to write to. |
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| 60 | # @param read_title Title of the georeference text. |
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| 61 | def __init__(self, |
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| 62 | zone=DEFAULT_ZONE, |
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| 63 | xllcorner=0.0, |
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| 64 | yllcorner=0.0, |
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| 65 | datum=DEFAULT_DATUM, |
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| 66 | projection=DEFAULT_PROJECTION, |
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| 67 | units=DEFAULT_UNITS, |
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| 68 | false_easting=DEFAULT_FALSE_EASTING, |
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| 69 | false_northing=DEFAULT_FALSE_NORTHING, |
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| 70 | NetCDFObject=None, |
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| 71 | ASCIIFile=None, |
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| 72 | read_title=None): |
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| 73 | """ |
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| 74 | input: |
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| 75 | NetCDFObject - a handle to the netCDF file to be written to |
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| 76 | ASCIIFile - a handle to the text file |
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| 77 | read_title - the title of the georeference text, if it was read in. |
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| 78 | If the function that calls this has already read the title line, |
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| 79 | it can't unread it, so this info has to be passed. |
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| 80 | If you know of a way to unread this info, then tell us. |
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| 81 | |
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| 82 | Note, the text file only saves a sub set of the info the |
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| 83 | points file does. Currently the info not written in text |
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| 84 | must be the default info, since ANUGA assumes it isn't |
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| 85 | changing. |
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| 86 | """ |
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| 87 | |
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| 88 | if zone is None: |
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| 89 | zone = DEFAULT_ZONE |
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| 90 | self.false_easting = int(false_easting) |
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| 91 | self.false_northing = int(false_northing) |
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| 92 | self.datum = datum |
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| 93 | self.projection = projection |
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| 94 | self.zone = int(zone) |
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| 95 | self.units = units |
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| 96 | self.xllcorner = float(xllcorner) |
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| 97 | self.yllcorner = float(yllcorner) |
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| 98 | |
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| 99 | if NetCDFObject is not None: |
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| 100 | self.read_NetCDF(NetCDFObject) |
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| 101 | |
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| 102 | if ASCIIFile is not None: |
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| 103 | self.read_ASCII(ASCIIFile, read_title=read_title) |
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| 104 | |
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| 105 | # Set flag for absolute points (used by get_absolute) |
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| 106 | self.absolute = num.allclose([self.xllcorner, self.yllcorner], 0) |
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| 107 | |
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| 108 | |
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| 109 | def get_xllcorner(self): |
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| 110 | return self.xllcorner |
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| 111 | |
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| 112 | ## |
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| 113 | # @brief Get the Y coordinate of the origin of this georef. |
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| 114 | def get_yllcorner(self): |
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| 115 | return self.yllcorner |
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| 116 | |
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| 117 | ## |
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| 118 | # @brief Get the zone of this georef. |
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| 119 | def get_zone(self): |
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| 120 | return self.zone |
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| 121 | |
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| 122 | ## |
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| 123 | # @brief Write <something> to an open NetCDF file. |
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| 124 | # @param outfile Handle to open NetCDF file. |
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| 125 | def write_NetCDF(self, outfile): |
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| 126 | outfile.xllcorner = self.xllcorner |
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| 127 | outfile.yllcorner = self.yllcorner |
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| 128 | outfile.zone = self.zone |
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| 129 | |
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| 130 | outfile.false_easting = self.false_easting |
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| 131 | outfile.false_northing = self.false_northing |
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| 132 | |
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| 133 | outfile.datum = self.datum |
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| 134 | outfile.projection = self.projection |
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| 135 | outfile.units = self.units |
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| 136 | |
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| 137 | ## |
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| 138 | # @brief Read data from an open NetCDF file. |
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| 139 | # @param infile Handle to open NetCDF file. |
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| 140 | def read_NetCDF(self, infile): |
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| 141 | self.xllcorner = float(infile.xllcorner[0]) |
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| 142 | self.yllcorner = float(infile.yllcorner[0]) |
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| 143 | self.zone = int(infile.zone[0]) |
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| 144 | |
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| 145 | try: |
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| 146 | self.false_easting = int(infile.false_easting[0]) |
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| 147 | self.false_northing = int(infile.false_northing[0]) |
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| 148 | |
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| 149 | self.datum = infile.datum |
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| 150 | self.projection = infile.projection |
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| 151 | self.units = infile.units |
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| 152 | except: |
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| 153 | pass |
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| 154 | |
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| 155 | if self.false_easting != DEFAULT_FALSE_EASTING: |
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| 156 | log.critical("WARNING: False easting of %f specified." |
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| 157 | % self.false_easting) |
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| 158 | log.critical("Default false easting is %f." % DEFAULT_FALSE_EASTING) |
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| 159 | log.critical("ANUGA does not correct for differences in " |
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| 160 | "False Eastings.") |
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| 161 | |
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| 162 | if self.false_northing != DEFAULT_FALSE_NORTHING: |
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| 163 | log.critical("WARNING: False northing of %f specified." |
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| 164 | % self.false_northing) |
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| 165 | log.critical("Default false northing is %f." |
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| 166 | % DEFAULT_FALSE_NORTHING) |
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| 167 | log.critical("ANUGA does not correct for differences in " |
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| 168 | "False Northings.") |
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| 169 | |
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| 170 | if self.datum.upper() != DEFAULT_DATUM.upper(): |
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| 171 | log.critical("WARNING: Datum of %s specified." % self.datum) |
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| 172 | log.critical("Default Datum is %s." % DEFAULT_DATUM) |
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| 173 | log.critical("ANUGA does not correct for differences in datums.") |
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| 174 | |
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| 175 | if self.projection.upper() != DEFAULT_PROJECTION.upper(): |
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| 176 | log.critical("WARNING: Projection of %s specified." |
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| 177 | % self.projection) |
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| 178 | log.critical("Default Projection is %s." % DEFAULT_PROJECTION) |
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| 179 | log.critical("ANUGA does not correct for differences in " |
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| 180 | "Projection.") |
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| 181 | |
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| 182 | if self.units.upper() != DEFAULT_UNITS.upper(): |
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| 183 | log.critical("WARNING: Units of %s specified." % self.units) |
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| 184 | log.critical("Default units is %s." % DEFAULT_UNITS) |
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| 185 | log.critical("ANUGA does not correct for differences in units.") |
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| 186 | |
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| 187 | ################################################################################ |
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| 188 | # ASCII files with geo-refs are currently not used |
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| 189 | ################################################################################ |
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| 190 | |
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| 191 | ## |
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| 192 | # @brief Write georef data to an open text file. |
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| 193 | # @param fd Handle to open text file. |
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| 194 | def write_ASCII(self, fd): |
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| 195 | fd.write(TITLE) |
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| 196 | fd.write(str(self.zone) + "\n") |
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| 197 | fd.write(str(self.xllcorner) + "\n") |
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| 198 | fd.write(str(self.yllcorner) + "\n") |
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| 199 | |
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| 200 | ## |
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| 201 | # @brief Read georef data from an open text file. |
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| 202 | # @param fd Handle to open text file. |
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| 203 | def read_ASCII(self, fd, read_title=None): |
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| 204 | try: |
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| 205 | if read_title == None: |
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| 206 | read_title = fd.readline() # remove the title line |
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| 207 | if read_title[0:2].upper() != TITLE[0:2].upper(): |
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| 208 | msg = ('File error. Expecting line: %s. Got this line: %s' |
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| 209 | % (TITLE, read_title)) |
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| 210 | raise TitleError, msg |
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| 211 | self.zone = int(fd.readline()) |
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| 212 | self.xllcorner = float(fd.readline()) |
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| 213 | self.yllcorner = float(fd.readline()) |
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| 214 | except SyntaxError: |
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| 215 | msg = 'File error. Got syntax error while parsing geo reference' |
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| 216 | raise ParsingError, msg |
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| 217 | |
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| 218 | # Fix some assertion failures |
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| 219 | if isinstance(self.zone, num.ndarray) and self.zone.shape == (): |
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| 220 | self.zone = self.zone[0] |
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| 221 | if (isinstance(self.xllcorner, num.ndarray) and |
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| 222 | self.xllcorner.shape == ()): |
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| 223 | self.xllcorner = self.xllcorner[0] |
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| 224 | if (isinstance(self.yllcorner, num.ndarray) and |
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| 225 | self.yllcorner.shape == ()): |
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| 226 | self.yllcorner = self.yllcorner[0] |
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| 227 | |
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| 228 | assert (type(self.xllcorner) == types.FloatType) |
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| 229 | assert (type(self.yllcorner) == types.FloatType) |
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| 230 | assert (type(self.zone) == types.IntType) |
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| 231 | |
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| 232 | ################################################################################ |
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| 233 | |
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| 234 | ## |
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| 235 | # @brief Change points to be absolute wrt new georef 'points_geo_ref'. |
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| 236 | # @param points The points to change. |
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| 237 | # @param points_geo_ref The new georef to make points absolute wrt. |
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| 238 | # @return The changed points. |
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| 239 | # @note If 'points' is a list then a changed list is returned. |
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| 240 | def change_points_geo_ref(self, points, points_geo_ref=None): |
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| 241 | """Change the geo reference of a list or numeric array of points to |
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| 242 | be this reference.(The reference used for this object) |
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| 243 | If the points do not have a geo ref, assume 'absolute' values |
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| 244 | """ |
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| 245 | import copy |
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| 246 | |
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| 247 | # remember if we got a list |
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| 248 | is_list = isinstance(points, list) |
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| 249 | |
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| 250 | points = ensure_numeric(points, num.float) |
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| 251 | |
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| 252 | # sanity checks |
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| 253 | if len(points.shape) == 1: |
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| 254 | #One point has been passed |
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| 255 | msg = 'Single point must have two elements' |
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| 256 | assert len(points) == 2, msg |
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| 257 | points = num.reshape(points, (1,2)) |
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| 258 | |
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| 259 | msg = 'Points array must be two dimensional.\n' |
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| 260 | msg += 'I got %d dimensions' %len(points.shape) |
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| 261 | assert len(points.shape) == 2, msg |
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| 262 | |
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| 263 | msg = 'Input must be an N x 2 array or list of (x,y) values. ' |
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| 264 | msg += 'I got an %d x %d array' %points.shape |
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| 265 | assert points.shape[1] == 2, msg |
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| 266 | |
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| 267 | # FIXME (Ole): Could also check if zone, xllcorner, yllcorner |
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| 268 | # are identical in the two geo refs. |
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| 269 | if points_geo_ref is not self: |
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| 270 | # If georeferences are different |
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| 271 | points = copy.copy(points) # Don't destroy input |
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| 272 | if not points_geo_ref is None: |
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| 273 | # Convert points to absolute coordinates |
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| 274 | points[:,0] += points_geo_ref.xllcorner |
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| 275 | points[:,1] += points_geo_ref.yllcorner |
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| 276 | |
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| 277 | # Make points relative to primary geo reference |
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| 278 | points[:,0] -= self.xllcorner |
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| 279 | points[:,1] -= self.yllcorner |
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| 280 | |
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| 281 | if is_list: |
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| 282 | points = points.tolist() |
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| 283 | |
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| 284 | return points |
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| 285 | |
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| 286 | def is_absolute(self): |
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| 287 | """Return True if xllcorner==yllcorner==0 indicating that points |
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| 288 | in question are absolute. |
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| 289 | """ |
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| 290 | |
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| 291 | # FIXME(Ole): It is unfortunate that decision about whether points |
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| 292 | # are absolute or not lies with the georeference object. Ross pointed this out. |
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| 293 | # Moreover, this little function is responsible for a large fraction of the time |
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| 294 | # using in data fitting (something in like 40 - 50%. |
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| 295 | # This was due to the repeated calls to allclose. |
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| 296 | # With the flag method fitting is much faster (18 Mar 2009). |
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| 297 | |
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| 298 | # FIXME(Ole): HACK to be able to reuse data already cached (18 Mar 2009). |
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| 299 | # Remove at some point |
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| 300 | if not hasattr(self, 'absolute'): |
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| 301 | self.absolute = num.allclose([self.xllcorner, self.yllcorner], 0) |
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| 302 | |
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| 303 | # Return absolute flag |
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| 304 | return self.absolute |
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| 305 | |
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| 306 | def get_absolute(self, points): |
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| 307 | """Given a set of points geo referenced to this instance, |
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| 308 | return the points as absolute values. |
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| 309 | """ |
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| 310 | |
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| 311 | # remember if we got a list |
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| 312 | is_list = isinstance(points, list) |
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| 313 | |
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| 314 | points = ensure_numeric(points, num.float) |
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| 315 | if len(points.shape) == 1: |
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| 316 | # One point has been passed |
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| 317 | msg = 'Single point must have two elements' |
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| 318 | if not len(points) == 2: |
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| 319 | raise ShapeError, msg |
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| 320 | |
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| 321 | |
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| 322 | msg = 'Input must be an N x 2 array or list of (x,y) values. ' |
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| 323 | msg += 'I got an %d x %d array' %points.shape |
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| 324 | if not points.shape[1] == 2: |
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| 325 | raise ShapeError, msg |
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| 326 | |
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| 327 | |
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| 328 | # Add geo ref to points |
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| 329 | if not self.is_absolute(): |
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| 330 | points = copy.copy(points) # Don't destroy input |
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| 331 | points[:,0] += self.xllcorner |
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| 332 | points[:,1] += self.yllcorner |
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| 333 | |
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| 334 | |
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| 335 | if is_list: |
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| 336 | points = points.tolist() |
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| 337 | |
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| 338 | return points |
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| 339 | |
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| 340 | ## |
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| 341 | # @brief Convert points to relative measurement. |
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| 342 | # @param points Points to convert to relative measurements. |
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| 343 | # @return A set of points relative to the geo_reference instance. |
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| 344 | def get_relative(self, points): |
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| 345 | """Given a set of points in absolute UTM coordinates, |
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| 346 | make them relative to this geo_reference instance, |
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| 347 | return the points as relative values. |
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| 348 | |
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| 349 | This is the inverse of get_absolute. |
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| 350 | """ |
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| 351 | |
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| 352 | # remember if we got a list |
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| 353 | is_list = isinstance(points, list) |
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| 354 | |
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| 355 | points = ensure_numeric(points, num.float) |
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| 356 | if len(points.shape) == 1: |
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| 357 | #One point has been passed |
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| 358 | msg = 'Single point must have two elements' |
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| 359 | if not len(points) == 2: |
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| 360 | raise ShapeError, msg |
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| 361 | |
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| 362 | if not points.shape[1] == 2: |
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| 363 | msg = ('Input must be an N x 2 array or list of (x,y) values. ' |
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| 364 | 'I got an %d x %d array' % points.shape) |
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| 365 | raise ShapeError, msg |
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| 366 | |
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| 367 | # Subtract geo ref from points |
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| 368 | if not self.is_absolute(): |
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| 369 | points = copy.copy(points) # Don't destroy input |
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| 370 | points[:,0] -= self.xllcorner |
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| 371 | points[:,1] -= self.yllcorner |
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| 372 | |
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| 373 | if is_list: |
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| 374 | points = points.tolist() |
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| 375 | |
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| 376 | return points |
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| 377 | |
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| 378 | ## |
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| 379 | # @brief ?? |
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| 380 | # @param other ?? |
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| 381 | def reconcile_zones(self, other): |
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| 382 | if other is None: |
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| 383 | other = Geo_reference() |
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| 384 | if (self.zone == other.zone or |
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| 385 | self.zone == DEFAULT_ZONE and |
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| 386 | other.zone == DEFAULT_ZONE): |
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| 387 | pass |
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| 388 | elif self.zone == DEFAULT_ZONE: |
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| 389 | self.zone = other.zone |
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| 390 | elif other.zone == DEFAULT_ZONE: |
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| 391 | other.zone = self.zone |
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| 392 | else: |
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| 393 | msg = ('Geospatial data must be in the same ' |
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| 394 | 'ZONE to allow reconciliation. I got zone %d and %d' |
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| 395 | % (self.zone, other.zone)) |
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| 396 | raise ANUGAError, msg |
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| 397 | |
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| 398 | #def easting_northing2geo_reffed_point(self, x, y): |
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| 399 | # return [x-self.xllcorner, y - self.xllcorner] |
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| 400 | |
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| 401 | #def easting_northing2geo_reffed_points(self, x, y): |
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| 402 | # return [x-self.xllcorner, y - self.xllcorner] |
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| 403 | |
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| 404 | ## |
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| 405 | # @brief Get origin of this geo_reference. |
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| 406 | # @return (zone, xllcorner, yllcorner). |
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| 407 | def get_origin(self): |
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| 408 | return (self.zone, self.xllcorner, self.yllcorner) |
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| 409 | |
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| 410 | ## |
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| 411 | # @brief Get a string representation of this geo_reference instance. |
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| 412 | def __repr__(self): |
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| 413 | return ('(zone=%i easting=%f, northing=%f)' |
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| 414 | % (self.zone, self.xllcorner, self.yllcorner)) |
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| 415 | |
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| 416 | ## |
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| 417 | # @brief Compare two geo_reference instances. |
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| 418 | # @param self This geo_reference instance. |
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| 419 | # @param other Another geo_reference instance to compare against. |
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| 420 | # @return 0 if instances have the same attributes, else 1. |
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| 421 | # @note Attributes are: zone, xllcorner, yllcorner. |
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| 422 | def __cmp__(self, other): |
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| 423 | # FIXME (DSG) add a tolerence |
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| 424 | if other is None: |
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| 425 | return 1 |
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| 426 | cmp = 0 |
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| 427 | if not (self.xllcorner == self.xllcorner): |
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| 428 | cmp = 1 |
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| 429 | if not (self.yllcorner == self.yllcorner): |
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| 430 | cmp = 1 |
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| 431 | if not (self.zone == self.zone): |
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| 432 | cmp = 1 |
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| 433 | return cmp |
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| 434 | |
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| 435 | |
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| 436 | ## |
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| 437 | # @brief Write a geo_reference to a NetCDF file (usually SWW). |
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| 438 | # @param origin A georef instance or parameters to create a georef instance. |
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| 439 | # @param outfile Path to file to write. |
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| 440 | # @return A normalized geo_reference. |
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| 441 | def write_NetCDF_georeference(origin, outfile): |
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| 442 | """Write georeference info to a netcdf file, usually sww. |
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| 443 | |
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| 444 | The origin can be a georef instance or parameters for a geo_ref instance |
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| 445 | |
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| 446 | outfile is the name of the file to be written to. |
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| 447 | """ |
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| 448 | |
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| 449 | geo_ref = ensure_geo_reference(origin) |
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| 450 | geo_ref.write_NetCDF(outfile) |
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| 451 | return geo_ref |
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| 452 | |
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| 453 | |
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| 454 | ## |
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| 455 | # @brief Convert an object to a georeference instance. |
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| 456 | # @param origin A georef instance or (zone, xllcorner, yllcorner) |
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| 457 | # @return A georef object, or None if 'origin' was None. |
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| 458 | def ensure_geo_reference(origin): |
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| 459 | """ |
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| 460 | Given a list/tuple of zone, xllcorner and yllcorner of a geo-ref object, |
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| 461 | return a geo ref object. |
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| 462 | |
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| 463 | If the origin is None, return None, so calling this function doesn't |
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| 464 | effect code logic |
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| 465 | """ |
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| 466 | |
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| 467 | if isinstance(origin, Geo_reference): |
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| 468 | geo_ref = origin |
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| 469 | elif origin is None: |
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| 470 | geo_ref = None |
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| 471 | else: |
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| 472 | geo_ref = apply(Geo_reference, origin) |
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| 473 | |
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| 474 | return geo_ref |
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| 475 | |
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| 476 | |
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| 477 | #----------------------------------------------------------------------- |
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| 478 | |
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| 479 | if __name__ == "__main__": |
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| 480 | pass |
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