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@rddaz2013
Created February 4, 2016 12:45

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  1. rddaz2013 created this gist Feb 4, 2016.
    625 changes: 625 additions & 0 deletions gistfile1.txt
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    # -*- coding: utf-8 -*-

    from __future__ import print_function, absolute_import

    import numpy, matplotlib, matplotlib.pyplot, math, re
    from scipy.interpolate import interp1d

    import CoolProp.CoolProp as CP

    from .Common import BasePlot
    from scipy import interpolate
    from scipy.spatial.kdtree import KDTree

    class IsoLine(object):
    def __init__(self):
    self.DEBUG = False

    # direct geometry
    self.X = None #
    self.Y = None #
    self.type = None #
    self.value = None #
    self.unit = None #
    self.opts = None #


    def InlineLabel(xv,yv,x = None, y= None, axis = None, fig = None):
    """
    This will give the coordinates and rotation required to align a label with
    a line on a plot
    """

    def ToPixelCoords(xv,yv,axis,fig):
    [Axmin,Axmax]=axis.get_xlim()
    [Aymin,Aymax]=axis.get_ylim()
    DELTAX_axis=Axmax-Axmin
    DELTAY_axis=Aymax-Aymin

    width=fig.get_figwidth()
    height=fig.get_figheight()
    pos=axis.get_position().get_points()
    [[Fxmin,Fymin],[Fxmax,Fymax]]=pos
    DELTAX_fig=width*(Fxmax-Fxmin)
    DELTAY_fig=height*(Fymax-Fymin)

    #Convert coords to pixels
    x=(xv-Axmin)/DELTAX_axis*DELTAX_fig+Fxmin
    y=(yv-Aymin)/DELTAY_axis*DELTAY_fig+Fymin

    return x,y

    def ToDataCoords(xv,yv,axis,fig):
    [Axmin,Axmax]=axis.get_xlim()
    [Aymin,Aymax]=axis.get_ylim()
    DELTAX_axis=Axmax-Axmin
    DELTAY_axis=Aymax-Aymin

    width=fig.get_figwidth()
    height=fig.get_figheight()
    pos=axis.get_position().get_points()
    [[Fxmin,Fymin],[Fxmax,Fymax]]=pos
    DELTAX_fig=(Fxmax-Fxmin)*width
    DELTAY_fig=(Fymax-Fymin)*height

    #Convert back to measurements
    x=(xv-Fxmin)/DELTAX_fig*DELTAX_axis+Axmin
    y=(yv-Fymin)/DELTAY_fig*DELTAY_axis+Aymin

    return x,y

    def get_x_y_dydx(xv,yv,x):
    """Get x and y coordinates and the linear interpolation derivative"""
    # Old implementation:
    ##Get the rotation angle
    #f = interp1d(xv, yv)
    #y = f(x)
    #h = 0.00001*x
    #dy_dx = (f(x+h)-f(x-h))/(2*h)
    #return x,y,dy_dx
    if len(xv)==len(yv)>1: # assure same length
    if len(xv)==len(yv)==2: # only two points
    if numpy.min(xv)<x<numpy.max(xv):
    dx = xv[1] - xv[0]
    dy = yv[1] - yv[0]
    dydx = dy/dx
    y = yv[0] + dydx * (x-xv[0])
    return x,y,dydx
    else:
    raise ValueError("Your coordinate has to be between the input values.")
    else:
    limit = 1e-10 # avoid hitting a point directly
    diff = numpy.array(xv)-x # get differences
    index = numpy.argmin(diff*diff) # nearest neighbour
    if (xv[index]<x<xv[index+1] # nearest below, positive inclination
    or xv[index]>x>xv[index+1]): # nearest above, negative inclination
    if diff[index]<limit:
    index = [index-1,index+1]
    else:
    index = [index, index+1]
    elif (xv[index-1]<x<xv[index] # nearest above, positive inclination
    or xv[index-1]>x>xv[index]): # nearest below, negative inclination
    if diff[index]<limit:
    index = [index-1,index+1]
    else:
    index = [index-1,index]
    xvnew = xv[index]
    yvnew = yv[index]
    return get_x_y_dydx(xvnew,yvnew,x) # Allow for a single recursion
    else:
    raise ValueError("You have to provide the same amount of x- and y-pairs with at least two entries each.")

    if axis is None:
    axis=matplotlib.pyplot.gca()

    if fig is None:
    fig=matplotlib.pyplot.gcf()

    if y is None and x is not None:
    trash=0
    (xv,yv)=ToPixelCoords(xv,yv,axis,fig)
    #x is provided but y isn't
    (x,trash)=ToPixelCoords(x,trash,axis,fig)

    #Get the rotation angle and y-value
    x,y,dy_dx = get_x_y_dydx(xv,yv,x)
    rot = numpy.arctan(dy_dx)/numpy.pi*180.

    elif x is None and y is not None:
    #y is provided, but x isn't

    _xv = xv[::-1]
    _yv = yv[::-1]
    #Find x by interpolation
    x = interp1d(yv, xv)(y)
    trash=0
    (xv,yv)=ToPixelCoords(xv,yv,axis,fig)
    (x,trash)=ToPixelCoords(x,trash,axis,fig)

    #Get the rotation angle and y-value
    x,y,dy_dx = get_x_y_dydx(xv,yv,x)
    rot = numpy.arctan(dy_dx)/numpy.pi*180.

    (x,y)=ToDataCoords(x,y,axis,fig)
    return (x,y,rot)


    def drawLines(Ref,lines,axis,plt_kwargs=None):
    """
    Just an internal method to systematically plot values from
    the generated 'line' dicts, method is able to cover the whole
    saturation curve. Closes the gap at the critical point and
    adds a marker between the two last points of bubble and
    dew line if they reach up to critical point.
    Returns an array of line objects that can be used to change
    the colour or style afterwards.
    """
    if not plt_kwargs is None:
    for line in lines:
    line['opts'] = plt_kwargs
    plottedLines = []
    if len(lines)==2 and (
    'q' in str(lines[0]['type']).lower() and 'q' in str(lines[1]['type']).lower()
    ) and (
    ( 0 == lines[0]['value'] and 1 == lines[1]['type'] ) or ( 1 == lines[0]['value'] and 0 == lines[1]['type'] ) ):
    # We plot the saturation curve
    bubble = lines[0]
    dew = lines[1]
    line, = axis.plot(bubble['x'],bubble['y'],**bubble['opts'])
    plottedLines.extend([line])
    line, = axis.plot(dew['x'], dew['y'], **dew['opts'])
    plottedLines.extend([line])
    # Do we need to test if this is T or p?
    Tmax = min(bubble['kmax'],dew['kmax'])
    if Tmax>CP.PropsSI(Ref,'Tcrit')-2e-5:
    axis.plot(numpy.r_[bubble['x'][-1],dew['x'][-1]],numpy.r_[bubble['y'][-1],dew['y'][-1]],**bubble['opts'])
    #axis.plot((bubble['x'][-1]+dew['x'][-1])/2.,(bubble['y'][-1]+dew['y'][-1])/2.,'o',color='Tomato')
    else:
    for line in lines:
    line, = axis.plot(line['x'],line['y'],**line['opts'])
    plottedLines.extend([line])

    return plottedLines


    class IsoLines(BasePlot):
    def __init__(self, fluid_ref, graph_type, iso_type, unit_system='SI', **kwargs):
    BasePlot.__init__(self, fluid_ref, graph_type, unit_system=unit_system,**kwargs)

    if not isinstance(iso_type, str):
    raise TypeError("Invalid iso_type input, expected a string")

    iso_type = iso_type.upper()
    if iso_type not in self.COLOR_MAP.keys() and iso_type != 'Q':
    raise ValueError('This kind of isoline is not supported for a ' \
    + str(graph_type) + \
    ' plot. Please choose from '\
    + str(self.COLOR_MAP.keys()) + ' or Q.')

    self.iso_type = iso_type

    def __set_axis_limits(self, swap_xy):
    """
    Generates limits for the axes in terms of x,y defined by 'plot'
    based on temperature and pressure.

    Returns a tuple containing ((xmin, xmax), (ymin, ymax))
    """
    # Get current axis limits, be sure to set those before drawing isolines
    # if no limits are set, use triple point and critical conditions
    X = [CP.PropsSI(self.graph_type[1],
    'T', 1.5*CP.PropsSI(self.fluid_ref, 'Tcrit'),
    'P', CP.PropsSI(self.fluid_ref, 'ptriple'),
    self.fluid_ref),
    CP.PropsSI(self.graph_type[1],
    'T', 1.1*CP.PropsSI(self.fluid_ref, 'Tmin'),
    'P', 1.5*CP.PropsSI(self.fluid_ref, 'pcrit'),
    self.fluid_ref),
    CP.PropsSI(self.graph_type[1],
    'T', 1.5*CP.PropsSI(self.fluid_ref, 'Tcrit'),
    'P', 1.5*CP.PropsSI(self.fluid_ref, 'pcrit'),
    self.fluid_ref),
    CP.PropsSI(self.graph_type[1],
    'T', 1.1*CP.PropsSI(self.fluid_ref, 'Tmin'),
    'P', CP.PropsSI(self.fluid_ref, 'ptriple'),
    self.fluid_ref)]

    Y = [CP.PropsSI(self.graph_type[0],
    'T', 1.5*CP.PropsSI(self.fluid_ref, 'Tcrit'),
    'P', CP.PropsSI(self.fluid_ref, 'ptriple'),
    self.fluid_ref),
    CP.PropsSI(self.graph_type[0],
    'T', 1.1*CP.PropsSI(self.fluid_ref, 'Tmin') ,
    'P', 1.5*CP.PropsSI(self.fluid_ref, 'pcrit'),
    self.fluid_ref),
    CP.PropsSI(self.graph_type[0],
    'T', 1.1*CP.PropsSI(self.fluid_ref, 'Tcrit'),
    'P', 1.5*CP.PropsSI(self.fluid_ref, 'pcrit'),
    self.fluid_ref),
    CP.PropsSI(self.graph_type[0],
    'T', 1.5*CP.PropsSI(self.fluid_ref, 'Tmin') ,
    'P', CP.PropsSI(self.fluid_ref, 'ptriple'),
    self.fluid_ref)]

    limits = [[min(X), max(X)], [min(Y), max(Y)]]
    if not self.axis.get_autoscalex_on():
    limits[0][0] = max([limits[0][0], min(self.axis.get_xlim())])
    limits[0][1] = min([limits[0][1], max(self.axis.get_xlim())])
    limits[1][0] = max([limits[1][0], min(self.axis.get_ylim())])
    limits[1][1] = min([limits[1][1], max(self.axis.get_ylim())])

    # Limits correction in case of KSI unit_system
    if self.unit_system == 'KSI':
    limits[0] = [l*self.KSI_SCALE_FACTOR[self.graph_type[1]] for l in limits[0]]
    limits[1] = [l*self.KSI_SCALE_FACTOR[self.graph_type[0]] for l in limits[1]]

    self.axis.set_xlim(limits[0])
    self.axis.set_ylim(limits[1])
    return limits

    def __plotRound(self, values):
    """
    A function round an array-like object while maintaining the
    amount of entries. This is needed for the isolines since we
    want the labels to look pretty (=rounding), but we do not
    know the spacing of the lines. A fixed number of digits after
    rounding might lead to reduced array size.
    """
    inVal = numpy.unique(numpy.sort(numpy.array(values)))
    output = inVal[1:] * 0.0
    digits = -1
    limit = 10
    lim = inVal * 0.0 + 10
    # remove less from the numbers until same length,
    # more than 10 significant digits does not really
    # make sense, does it?
    while len(inVal) > len(output) and digits < limit:
    digits += 1
    val = ( numpy.around(numpy.log10(numpy.abs(inVal))) * -1) + digits + 1
    val = numpy.where(val < lim, val, lim)
    val = numpy.where(val >-lim, val, -lim)
    output = numpy.zeros(inVal.shape)
    for i in range(len(inVal)):
    output[i] = numpy.around(inVal[i],decimals=int(val[i]))
    output = numpy.unique(output)
    return output

    def get_isolines(self, iso_range=[], num=None, rounding=False):
    """
    This is the core method to obtain lines in the dimensions defined
    by 'plot' that describe the behaviour of fluid 'Ref'. The constant
    value is determined by 'iName' and has the values of 'iValues'.

    'iValues' is an array-like object holding at least one element. Lines
    are calculated for every entry in 'iValues'. If the input 'num' is
    larger than the amount of entries in 'iValues', an internally defined
    pattern is used to calculate an appropriate line spacing between the maximum
    and minimum values provided in 'iValues'.

    Returns lines[num] - an array of dicts containing 'x' and 'y'
    coordinates for bubble and dew line. Additionally, the dict holds
    the keys 'label' and 'opts', those can be used for plotting as well.
    """
    if iso_range is None or (len(iso_range) == 1 and num != 1):
    raise ValueError('Automatic interval detection for isoline \
    boundaries is not supported yet, use the \
    iso_range=[min, max] parameter.')

    if len(iso_range) == 2 and num is None:
    raise ValueError('Please specify the number of isoline you want \
    e.g. num=10')

    iso_range = numpy.sort(numpy.unique(iso_range))

    def generate_ranges(xmin, xmax, num):
    if self.iso_type in ['P', 'D']:
    return numpy.logspace(math.log(xmin, 2.),
    math.log(xmax, 2.),
    num=num,
    base=2.)
    return numpy.linspace(xmin, xmax, num=num)

    # Generate iso ranges
    if len(iso_range) == 2:
    iso_range = generate_ranges(iso_range[0], iso_range[1], num)
    #iso_range = plotRound(iso_range)
    #else:
    # TODO: Automatic interval detection
    # iVal = [CP.PropsSI(iName,'T',T_c[i],'D',rho_c[i],Ref) for i in range(len(T_c))]
    # iVal = patterns[iName]([numpy.min(iVal),numpy.max(iVal),num])

    if rounding:
    iso_range = self.__plotRound(iso_range)

    switch_xy_map = {'D': ['TS', 'PH', 'PS'],
    'S': ['PH', 'PD', 'PT'],
    'T': ['PH', 'PS'],
    'H': ['PD']}
    #TS: TD is defined, SD is not
    #PH: PD is defined, HD is not
    #PS: PD is defined, SD is not
    #PH: PS is more stable than HS
    #PD: PS is defined, DS is not
    #PT: PS is defined, TS is not
    #PH: PT is defined, HT is not
    #PS: PT is defined, ST is not
    #PD: PH is defined, DH is not

    iso_error_map = {'TD': ['S', 'H'],
    'HS': ['T', 'D'],}

    switch_xy = False
    if self.iso_type in ['D', 'S', 'T', 'H']:
    if self.graph_type in switch_xy_map[self.iso_type]:
    switch_xy = True

    if self.graph_type in ['TD', 'HS']:
    if self.iso_type in iso_error_map[self.graph_type]:
    raise ValueError('You should not reach this point!')

    axis_limits = self.__set_axis_limits(switch_xy)
    req_prop = self.graph_type[0]
    prop2_name = self.graph_type[1]
    if switch_xy:
    axis_limits.reverse()
    req_prop = self.graph_type[1]
    prop2_name = self.graph_type[0]

    # Calculate the points
    if self.iso_type == 'Q':
    lines = self._get_sat_lines(x=iso_range)
    return lines

    # TODO: Determine saturation state if two phase region present
    x_range = numpy.linspace(axis_limits[0][0], axis_limits[0][1], 1000.)
    x_mesh = [x_range for i in iso_range]

    plot_data = self._get_fluid_data(req_prop,
    self.iso_type, iso_range,
    prop2_name, x_mesh)

    if switch_xy:
    plot_data = plot_data[::-1]

    lines = []
    for j in range(len(plot_data[0])):
    line = {
    'x': plot_data[0][j],
    'y': plot_data[1][j],
    # TODO
    'label': "", #_getIsoLineLabel(self.iso_type, iso_range[j]),
    'type': self.iso_type,
    'opts': {'color': self.COLOR_MAP[self.iso_type], 'lw':0.75, 'alpha':0.5 }
    }
    lines.append(line)

    return lines

    def draw_isolines(self, iso_range, num=None, rounding=False):
    """
    Draw lines with constant values of type 'which' in terms of x and y as
    defined by 'plot'. 'iMin' and 'iMax' are minimum and maximum value between
    which 'num' get drawn.

    There should also be helpful error messages...
    """
    if iso_range is None or (len(iso_range) == 1 and num != 1):
    raise ValueError('Automatic interval detection for isoline \
    boundaries is not supported yet, use the \
    iso_range=[min, max] parameter.')

    if len(iso_range) == 2 and num is None:
    raise ValueError('Please specify the number of isoline you want \
    e.g. num=10')

    if self.iso_type == 'all':
    raise ValueError('Plotting all lines automatically is not \
    supported, yet..')

    if self.iso_type != 'all':
    lines = self.get_isolines(iso_range, num, rounding)
    drawn_lines = drawLines(self.fluid_ref, lines, self.axis)
    self._plot_default_annotations()
    return drawn_lines
    #else:
    # # TODO: assign limits to values automatically
    # ll = _getIsoLineIds(plot)
    # if not len(ll)==len(iValues):
    # raise ValueError('Please provide a properly sized array of bounds.')
    # for c,l in enumerate(ll):
    # drawIsoLines(Ref, plot, l, iValues=iValues[c], num=num, axis=axis, fig=fig)


    class PropsPlot(BasePlot):
    def __init__(self, fluid_name, graph_type, units = 'KSI', reciprocal_density = False, **kwargs):
    """
    Create graph for the specified fluid properties

    Parameters
    ----------
    fluid_ref : string
    The name of the fluid to be plotted
    graph_type : string
    The graph type to be plotted
    axis : :func:`matplotlib.pyplot.gca()`, Optional
    The current axis system to be plotted to.
    Default: create a new axis system
    fig : :func:`matplotlib.pyplot.figure()`, Optional
    The current figure to be plotted to.
    Default: create a new figure
    units : string, ['KSI','SI']
    Select the units used for the plotting. 'KSI' is kPa, kJ, K; 'SI' is Pa, J, K
    reciprocal_density : bool
    If True, 1/rho will be plotted instead of rho

    Examples
    --------
    >>> from CoolProp.Plots import PropsPlot
    >>> plt = PropsPlot('Water', 'Ph')
    >>> plt.show()

    >>> plt = PropsPlot('n-Pentane', 'Ts')
    >>> plt.set_axis_limits([-0.5, 1.5, 300, 530])
    >>> plt.draw_isolines('Q', [0.1, 0.9])
    >>> plt.draw_isolines('P', [100, 2000])
    >>> plt.draw_isolines('D', [2, 600])
    >>> plt.show()

    .. note::

    See the online documentation for a list of the available fluids and
    graph types
    """
    BasePlot.__init__(self, fluid_name, graph_type, unit_system=units, **kwargs)

    self.smin = kwargs.get('smin', None)
    self.smax = kwargs.get('smax', None)

    self._draw_graph()

    def __draw_region_lines(self):
    lines = self._get_sat_lines(kind='T',
    smin=self.smin,
    smax=self.smax)
    drawLines(self.fluid_ref, lines, self.axis)

    def _draw_graph(self):
    self.__draw_region_lines()
    self._plot_default_annotations()

    def draw_isolines(self, iso_type, iso_range, num=10, rounding=False):
    iso_lines = IsoLines(self.fluid_ref,
    self.graph_type,
    iso_type, unit_system = self.unit_system,
    axis=self.axis)
    iso_lines.draw_isolines(iso_range, num, rounding)


    def Ts(Ref, Tmin=None, Tmax=None, show=False, axis=None, *args, **kwargs):
    """
    Deprecated. Use :py:func:`CoolProps.Plots.PropsPlot`
    """
    plt = PropsPlot(Ref, 'Ts', smin=Tmin, smax=Tmax, axis=axis, *args, **kwargs)
    plt._draw_graph()
    if show:
    plt.show()
    else:
    plt._draw_graph()
    return plt.axis


    def Ph(Ref, Tmin=None, Tmax=None, show=False, axis=None, *args, **kwargs):
    """
    Deprecated. Use :py:func:`CoolProps.Plots.PropsPlot`
    """
    plt = PropsPlot(Ref, 'Ph', smin=Tmin, smax=Tmax, axis=axis, *args, **kwargs)
    if show:
    plt.show()
    else:
    plt._draw_graph()
    return plt.axis


    def Ps(Ref, Tmin=None, Tmax=None, show=False, axis=None, *args, **kwargs):
    """
    Deprecated. Use :py:func:`CoolProps.Plots.PropsPlot`
    """
    plt = PropsPlot(Ref, 'Ps', smin=Tmin, smax=Tmax, axis=axis, *args, **kwargs)
    if show:
    plt.show()
    else:
    plt._draw_graph()
    return plt.axis

    def PT(Ref, Tmin=None, Tmax=None, show=False, axis=None, *args, **kwargs):
    """
    Deprecated. Use :py:func:`CoolProps.Plots.PropsPlot`
    """
    plt = PropsPlot(Ref, 'PT', smin=Tmin, smax=Tmax, axis=axis, *args, **kwargs)
    if show:
    plt.show()
    else:
    plt._draw_graph()
    return plt.axis

    def Prho(Ref, Tmin=None, Tmax=None, show=False, axis=None, *args, **kwargs):
    """
    """
    plt = PropsPlot(Ref, 'PD', smin=Tmin, smax=Tmax, axis=axis, *args, **kwargs)
    if show:
    plt.show()
    else:
    plt._draw_graph()
    return plt.axis

    def Trho(Ref, Tmin=None, Tmax=None, show=False, axis=None, *args, **kwargs):
    """
    Deprecated. Use :py:func:`CoolProps.Plots.PropsPlot`
    """
    plt = PropsPlot(Ref, 'TD', smin=Tmin, smax=Tmax, axis=axis, *args, **kwargs)
    if show:
    plt.show()
    else:
    plt._draw_graph()
    return plt.axis

    def hs(Ref, Tmin=None, Tmax=None, show=False, axis=None, *args, **kwargs):
    """
    Deprecated. Use :py:func:`CoolProps.Plots.PropsPlot`
    """
    plt = PropsPlot(Ref, 'hs', smin=Tmin, smax=Tmax, axis=axis, *args, **kwargs)
    if show:
    plt.show()
    else:
    plt._draw_graph()
    return plt.axis

    def drawIsoLines(Ref, plot, which, iValues=[], num=0, show=False, axis=None):
    """
    Draw lines with constant values of type 'which' in terms of x and y as
    defined by 'plot'. 'iMin' and 'iMax' are minimum and maximum value
    between which 'num' get drawn.

    :Note:
    :func:`CoolProps.Plots.drawIsoLines` will be depreciated in future
    releases and replaced with :func:`CoolProps.Plots.IsoLines`

    Parameters
    ----------
    Ref : str
    The given reference fluid
    plot : str
    The plot type used
    which : str
    The iso line type
    iValues : list
    The list of constant iso line values
    num : int, Optional
    The number of iso lines
    (Default: 0 - Use iValues list only)
    show : bool, Optional
    Show the current plot
    (Default: False)
    axis : :func:`matplotlib.pyplot.gca()`, Optional
    The current axis system to be plotted to.
    (Default: create a new axis system)

    Examples
    --------
    >>> from matplotlib import pyplot
    >>> from CoolProp.Plots import Ts, drawIsoLines
    >>>
    >>> Ref = 'n-Pentane'
    >>> ax = Ts(Ref)
    >>> ax.set_xlim([-0.5, 1.5])
    >>> ax.set_ylim([300, 530])
    >>> quality = drawIsoLines(Ref, 'Ts', 'Q', [0.3, 0.5, 0.7, 0.8], axis=ax)
    >>> isobars = drawIsoLines(Ref, 'Ts', 'P', [100, 2000], num=5, axis=ax)
    >>> isochores = drawIsoLines(Ref, 'Ts', 'D', [2, 600], num=7, axis=ax)
    >>> pyplot.show()
    """
    isolines = IsoLines(Ref, plot, which, axis=axis)
    lines = isolines.draw_isolines(iValues, num)
    if show:
    isolines.show()
    return lines