Class: Kamelopard::Functions::LatLonInterp

Inherits:
FunctionMultiDim show all
Defined in:
lib/kamelopard/function.rb

Overview

Interpolates between two points, choosing the shortest great-circle distance between the points.

Instance Attribute Summary collapse

Attributes inherited from FunctionMultiDim

#ndims

Attributes inherited from Function

#append, #compose, #end, #max, #min, #start, #verbose

Instance Method Summary collapse

Methods inherited from FunctionMultiDim

#compose=

Methods inherited from Function

#get_value, interpolate

Constructor Details

#initialize(a, b) ⇒ LatLonInterp

Returns a new instance of LatLonInterp.



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# File 'lib/kamelopard/function.rb', line 185

def initialize(a, b)
    super()
    (lat1, lon1) = [a.latitude, a.longitude]
    (lat2, lon2) = [b.latitude, b.longitude]

#                if (lat2 - lat1).abs > 90 
#                    if lat2 > 0
#                        lat2 = lat2 - 180
#                    else
#                        lat2 = lat2 + 180
#                    end
#                end

    @latfunc = yield lat1, lat2, :latitude

    if (lon2 - lon1).abs > 180 
        if lon2 > 0
            lon2 = lon2 - 360
        else
            lon2 = lon2 + 360
        end
    end

    @lonfunc = yield lon1, lon2, :longitude
end

Instance Attribute Details

#latfunc ⇒ Object (readonly)

a and b are points. This function will yield three variables, twice, expecting the block to return a one-dimensional function interpolating between the first two variables it was sent. The third variable yielded is a symbol, either :latitude or :longitude, to indicate which set of coordinates is being processed.



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# File 'lib/kamelopard/function.rb', line 183

def latfunc
  @latfunc
end

#lonfunc ⇒ Object (readonly)

a and b are points. This function will yield three variables, twice, expecting the block to return a one-dimensional function interpolating between the first two variables it was sent. The third variable yielded is a symbol, either :latitude or :longitude, to indicate which set of coordinates is being processed.



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# File 'lib/kamelopard/function.rb', line 183

def lonfunc
  @lonfunc
end

Instance Method Details

#run_function(x) ⇒ Object 



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# File 'lib/kamelopard/function.rb', line 211

def run_function(x)
    (lat, lon) = [@latfunc.run_function(x), @lonfunc.run_function(x)]
    lat = lat - 180 if lat > 90
    lat = lat + 180 if lat < -90
    lon = lon - 360 if lon > 180
    lon = lon + 360 if lon < -180
    return [lat, lon]
end