bar and hist functions

CHANGELOG.md

@@ -8,6 +8,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ### Added
 
+- `hist` Histogram plot.
+- `bar` Bar graph.
 - `scatter` Scatter plot.
 - `stem` Plot discrete sequence data.
 - `stairs` Stairstep graph.

modules/graphics/functions/bar.m

@@ -0,0 +1,172 @@
+%=============================================================================
+% Copyright (c) 2023-present Allan CORNET (Nelson)
+%=============================================================================
+% This file is part of the Nelson.
+%=============================================================================
+% LICENCE_BLOCK_BEGIN
+% SPDX-License-Identifier: LGPL-3.0-or-later
+% LICENCE_BLOCK_END
+%=============================================================================
+function varargout = bar(varargin)
+  % basic implementation (stacked, group not yet implemented)
+  % bar(y)
+  % bar(x, y)
+  % bar(..., width)
+  % bar(..., color)
+  % bar(ax, ...)
+  % b = bar(...)
+  % b = bar(ax, x, y, width, color, ...)
+  narginchk(1, 100);
+  nargoutchk(0, 1);
+  [parent, X, Y, width, color, otherProperties] = parseArguments(varargin);
+  h = barPlot(parent, X, Y, width, color, otherProperties);
+  if (nargout == 1)
+    varargout{1} = h;
+  end
+end
+%=============================================================================
+function [parent, X, Y, width, color, otherProperties] = parseArguments(inputArguments)
+  nbInputArguments = length(inputArguments);
+  if (nbInputArguments >= 1)
+    if (isscalar(inputArguments{1}) && (isgraphics(inputArguments{1}, 'axes') || isgraphics(inputArguments{1}, 'hggroup')))
+      parent = inputArguments{1}(1);
+      inputArguments = inputArguments(2:end);
+      nbInputArguments = nbInputArguments - 1;
+    else
+      parent = newplot();
+    end
+  else
+    parent = newplot();
+  end
+  defaultWidth = 0.8;
+  defaultColor = getColorAndUpdateIndex(parent);
+
+  supportedColorString = string(getColorShortNameList());
+  isString = @(x) (ischar(x) || isStringScalar(x)) && ~matches(convertCharsToStrings(x), supportedColorString);
+  firstString = find (cellfun(isString, inputArguments), 1);
+  if (isempty(firstString))
+    firstString = nbInputArguments + 1;
+  end
+
+  if (firstString > nbInputArguments)
+    otherProperties = struct([]);
+  else
+    otherProperties = inputArguments(firstString:end);
+    otherProperties = struct(otherProperties{:});
+    inputArguments = inputArguments(1:firstString-1);
+  end
+  nbInputArguments = length(inputArguments);
+
+  if nbInputArguments == 1
+    [X, Y, width, color] = parseOneArgument(inputArguments, defaultWidth, defaultColor);
+  end
+
+  if nbInputArguments == 2
+    [X, Y, width, color] = parseTwoArguments(inputArguments, defaultWidth, defaultColor);
+  end
+
+  if nbInputArguments == 3
+    [X, Y, width, color] = parseThreeArguments(inputArguments, defaultWidth, defaultColor);
+  end
+  if min(size(X)) == 1, X = X(:); end
+  if min(size(Y)) == 1, Y = Y(:); end
+end
+%=============================================================================
+function [X, Y, width, color] = parseThreeArguments(inputArguments, defaultWidth, defaultColor)
+  width = defaultWidth;
+  color = defaultColor;
+  X = inputArguments{1};
+  X = X(:)';
+  if isscalar(inputArguments{2})
+    if isnumeric(inputArguments{2})
+      width = inputArguments{2};
+    elseif ischar(inputArguments{2}) || isStringScalar(inputArguments{2})
+      color = convertStringsToChars(inputArguments{2});
+    else
+      error(_('Unrecognized option for second argument.'));
+    end
+  else
+    Y = inputArguments{2};
+    Y = Y(:)';
+  end
+  if isnumeric(inputArguments{3})
+    width = inputArguments{3};
+  elseif ischar(inputArguments{3}) || isStringScalar(inputArguments{3})
+    color = convertStringsToChars(inputArguments{3});
+  else
+    error(_('Unrecognized option for third argument.'));
+  end
+end
+%=============================================================================
+function [X, Y, width, color] = parseTwoArguments(inputArguments, defaultWidth, defaultColor)
+  width = defaultWidth;
+  color = defaultColor;
+  if isscalar(inputArguments{2})
+    if isnumeric(inputArguments{2})
+      width = inputArguments{2};
+    elseif ischar(inputArguments{2}) || isStringScalar(inputArguments{2})
+      color = convertStringsToChars(inputArguments{2})
+    else
+      error(_('Unrecognized option for second argument.'));
+    end
+    Y = inputArguments{1};
+    Y = Y(:)';
+    X = linspace(0, size(Y, 2) - 1, size(Y, 2)) + 1;
+  else
+    X = inputArguments{1};
+    X = X(:)';
+    Y = inputArguments{2};
+    Y = Y(:)';
+  end
+end
+%=============================================================================
+function [X, Y, width, color] = parseOneArgument(inputArguments, defaultWidth, defaultColor)
+  width = defaultWidth;
+  color = defaultColor;
+  Y = inputArguments{1};
+  Y = Y(:)';
+  X = linspace(0, size(Y, 2) - 1, size(Y, 2)) + 1;
+end
+%=============================================================================
+function h = barPlot(parent, X, Y,width, color, otherProperties)
+  needUpdateXLabel = false;
+  if isstring(X)
+    needUpdateXLabel = true;
+    xLabels = X;
+    X = 1:length(X);
+    X = reshape(X, size(xLabels))   
+  end
+  df = width * diff(X) / 2;
+  df(end + 1) = df(end);
+  x_r = X(1:end) - df;
+  x_l = X(1:end) + df;
+
+  n = length(X);
+  onesXr = ones(size(x_r));
+  vertices = [x_r, zeros(size(x_r)), onesXr; ...
+  x_r, Y, onesXr; ...
+  x_l, Y, onesXr; ...
+  x_l, zeros(size(x_l)), onesXr];
+
+  ind = (1:n)';
+  faces = [ind, ind + n, ind + 2 * n, ind + 3 * n];
+  barProperties = struct('Parent', parent, 'Faces', faces, 'Vertices', vertices, 'FaceColor', color);
+  for name = fieldnames(otherProperties)'
+    barProperties.(name{1}) = otherProperties.(name{1});
+  end
+  barProperties = reshape([fieldnames(barProperties)'; struct2cell(barProperties)'], 1, []);
+  h = patch(barProperties{:});
+  if needUpdateXLabel
+    ax = gca();
+    ticks = ax.XTickLabel;
+    res = cell(1, numel(ticks));
+    for i = 1:numel(X)
+      idx = find(strcmp(ticks, num2str(X(i))));
+      if ~isempty(idx)
+        res{idx} = xLabels(i);
+      end
+    end
+    ax.XTickLabel = string(res);
+  end
+end
+%=============================================================================

modules/graphics/functions/hist.m

@@ -0,0 +1,126 @@
+%=============================================================================
+% Copyright (c) 2023-present Allan CORNET (Nelson)
+%=============================================================================
+% This file is part of the Nelson.
+%=============================================================================
+% LICENCE_BLOCK_BEGIN
+% SPDX-License-Identifier: LGPL-3.0-or-later
+% LICENCE_BLOCK_END
+%=============================================================================
+function varargout = hist(varargin)
+
+  narginchk(1, 100);
+  nargoutchk(0, 2);
+
+  inputArguments = varargin;
+  nbInputArguments = length(inputArguments);
+  if (nargout == 0)
+    if (nbInputArguments >= 1)
+      if (isscalar(inputArguments{1}) && (isgraphics(inputArguments{1}, 'axes') || isgraphics(inputArguments{1}, 'hggroup')))
+        parent = inputArguments{1}(1);
+        inputArguments = inputArguments(2:end);
+        nbInputArguments = nbInputArguments - 1;
+      else
+        parent = newplot();
+      end
+    else
+      parent = newplot();
+    end
+  end
+
+  y = inputArguments{1};
+  inputArguments = inputArguments(2:end);
+  nbInputArguments = length(inputArguments);
+
+  asVector = isvector(y);
+  y = y(:);
+
+  if ~isreal(y)
+    y = real(y);
+  end 
+  max_val = max (y(:));
+  min_val = min (y(:));
+
+  if (nbInputArguments == 0)
+    n = 10;
+    x = [0.5:n]'/n;
+    x = x * (max_val - min_val) + ones(size(x)) * min_val;
+  else
+    x = inputArguments{1};
+    inputArguments = inputArguments(2:end);
+    if (isscalar(x))
+      n = x;
+      if (n <= 0)
+        error(_('Second argument must be positive.'));
+      end
+      x = [0.5:n]'/n;
+      x = x * (max_val - min_val) + ones (size (x)) * min_val;
+    elseif (isreal (x))
+      if (isvector (x))
+        x = x(:);
+      end
+      x = sort (x);
+    else
+      error(_('Second argument must be a scalar or vector.'));
+    end
+  end
+
+  x = double (x);
+  y = double (y);
+  freq = computesFreq(x, y);
+
+  if (nbInputArguments > 2 && ~ischar(inputArguments{iarg}))
+    norm = inputArguments{iarg};
+    inputArguments = inputArguments(2:end);
+    freq = freq / size(y, 1) * norm;
+  end
+
+  if nargout == 0
+    if (size(freq, 2) == 1)
+      width = 1;
+    else
+      width = 0.8;
+    end
+    h = bar(parent, x, freq, width, inputArguments{:});
+  end
+
+  if nargout > 0
+    if ~asVector
+      varargout{1} = freq;
+    else
+      varargout{1} = freq';
+    end
+  end
+
+  if nargout > 1
+    if ~asVector
+      varargout{2} = x;
+    else
+      varargout{2} = x';
+    end
+  end
+end
+%=============================================================================
+function freq = computesFreq(x, y)
+  cutout = (x(1:end - 1,:) + x(2:end, :)) / 2;
+  n = size(x, 1);
+  offset = 30;
+  withLoopOnN = (n < offset && size(x, 2) == 1);
+  if ~withLoopOnN
+    [s, idx] = sort([y; cutout]);
+    lenY = size(y, 1);
+    histValues = cumsum(idx <= lenY);
+    x1 = zeros(1, size(y, 2));
+    x2 = reshape(histValues(idx > lenY), size(cutout));
+    x3 = histValues(end, :) - sum(isnan(y));
+    histValues = [x1; x2; x3];
+  else
+    histValues = zeros (n + 1, size(y, 2));
+    for i = 1:n-1
+      histValues(i + 1, :) = sum(y <= cutout(i));
+    end
+    histValues(n + 1, :) = sum(~isnan(y));
+  end
+  freq = diff(histValues);
+end
+%=============================================================================