Module: Num4SimDiffLib

Extended by:
FFI::Library
Defined in:
lib/num4simdiff.rb

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.cnvPt2RbAry(n, pt) ⇒ Object 



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# File 'lib/num4simdiff.rb', line 85

def cnvPt2RbAry(n, pt)
  rbAry = n.times.map { |i|
     pt.get_double(i * Fiddle::SIZEOF_DOUBLE)
  }
  return rbAry  
end

.cnvRbAry2pt(n, ary) ⇒ Object 



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# File 'lib/num4simdiff.rb', line 78

def cnvRbAry2pt(n, ary)
    yi_ptr = FFI::MemoryPointer.new(:double, n)
    n.times.map { |i|
        yi_ptr.put_double(i * Fiddle::SIZEOF_DOUBLE, ary[i].to_f)
    }
    return yi_ptr   
end

.eulerMethod(yi, x, h, func1, func2) ⇒ Object 



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# File 'lib/num4simdiff.rb', line 58

def eulerMethod(yi, x, h, func1, func2)
  yi_ptr = cnvRbAry2pt(2, yi)
  yi_1_ptr = eulerMethodFFI(yi_ptr, x, h, func1, func2)
  yi_1 = cnvPt2RbAry(2, yi_1_ptr)
  return 1 + yi_1[0] + 0.5 * yi_1[1]
end

.heunMethod(yi, x, h, func1, func2) ⇒ Object 



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# File 'lib/num4simdiff.rb', line 64

def heunMethod(yi, x, h, func1, func2)
  yi_ptr = cnvRbAry2pt(2, yi)
  yi_1_ptr = heunMethodFFI(yi_ptr, x, h, func1, func2)
  yi_1 = cnvPt2RbAry(2, yi_1_ptr)
  return 1 + yi_1[0] + 0.5 * yi_1[1] 
end

.rungeKuttaMethod(yi, x, h, func1, func2) ⇒ Object 



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# File 'lib/num4simdiff.rb', line 70

def rungeKuttaMethod(yi, x, h, func1, func2)
  yi_ptr = cnvRbAry2pt(2, yi)
  yi_1_ptr = rungeKuttaMethodFFI(yi_ptr, x, h, func1, func2)
  yi_1 = cnvPt2RbAry(2, yi_1_ptr)
  return 1 + yi_1[0] + 0.5 * yi_1[1]
end

Instance Method Details

#f(x, dx) {|x| ... } ⇒ double

dy = f(x, dx)

Yields:

  • (x) —

    dy = f(x, dx)

Yield Parameters:

  • x (double) —

    xiの値

  • dx (double) —

    xiの値

Returns:

  • (double) —

    xiに対するyの値



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# File 'lib/num4simdiff.rb', line 16

callback   :f, [:double, :double], :double