strjust function + tf display centered

CHANGELOG.md

@@ -14,6 +14,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - `cell2mat` Convert cell array of matrices to single matrix.
 - [#948](http://github.com/Nelson-numerical-software/nelson/issues/948) `blkdiag` Create a block diagonal matrix from 2D matrices of different sizes.
 - `kron` Kronecker tensor product.
+- `strjust` Justify strings.
 
 - control system module (part 1):
   - [#967](http://github.com/Nelson-numerical-software/nelson/issues/967) control system module template.

modules/control_system/functions/@tf/display.m

@@ -44,15 +44,22 @@ function display(varargin)
       numeratorString = stringPoly(numerators{k, q}, TF.Variable);
       haveNoNumerator = isempty(numeratorString);
       denominatorString = stringPoly(denominator{k, q}, TF.Variable);
-      lengthDiff = length(denominatorString) - length(numeratorString);
-      if (lengthDiff > 0)
-        spacesToAdd = repmat(' ', 1, floor(lengthDiff / 2));
-        numeratorString = [spacesToAdd, numeratorString];
-      end
+      isOneString = strcmp(denominatorString, ' 1');
+
+      maxLen = max([length(denominatorString), length(numeratorString)]);
+      spacesToAdd = repmat(' ', 1, maxLen - length(numeratorString));
+      numeratorString = [spacesToAdd, numeratorString];
+      spacesToAdd = repmat(' ', 1, maxLen - length(denominatorString));
+      denominatorString = [spacesToAdd, denominatorString];
+      ce = strjust({numeratorString, denominatorString}, 'center');
+      numeratorString = ce{1};
+      denominatorString = ce{2};
+      numeratorString = deblank(numeratorString);
+      denominatorString = deblank(denominatorString);
       dashString = getDashedLine(numeratorString, denominatorString);
-      
+
       if (m ~= 1)
-        if (strcmp(denominatorString, ' 1') == true)
+        if isOneString
           if ~haveNoNumerator
             disp(['  ',sprintf(_('%d:'), k), '  ', numeratorString]);
           else
@@ -74,8 +81,7 @@ function display(varargin)
         end
       end
 
-
-      if (strcmp(denominatorString, ' 1') == false && ~haveNoNumerator)
+      if (~isOneString && ~haveNoNumerator)
         disp(['  ', dashString]);
         disp(['  ', denominatorString]);
       end
@@ -101,9 +107,35 @@ function display(varargin)
   end
 end
 %=============================================================================
+function [numeratorString, dashString, denominatorString] = uniformizeStrings(numeratorString, dashString, denominatorString)
+
+  str = string({numeratorString, dashString, denominatorString});
+  max_length = max(strlength(str));
+
+  spaces_numeratorString = (max_length - length(numeratorString));
+  spaces_dashString = (max_length - length(dashString));
+  spaces_denominatorString = (max_length - length(denominatorString));
+
+  text = strjust({dashString, denominatorString}, 'center');
+  dashString = text{1};
+  denominatorString = text{2};
+
+  str{1} = [repmat(' ', 1, spaces_numeratorString), str{1}];
+  str{2} = [repmat(' ', 1, spaces_dashString), str{2}];
+  str{3} = [repmat(' ', 1, spaces_denominatorString), str{3}];
+
+  str = strjust(str, 'center');
+  numeratorString = deblank(str{1});
+  dashString = deblank(str{2});
+  denominatorString = deblank(str{3});
+end
+%=============================================================================
 function dash = getDashedLine(numeratorString, denominatorString)
   dash = '';
-  lenDash = max(length(numeratorString), length(denominatorString)) + 1;
+  lenDash = max(length(numeratorString), length(denominatorString));
+  if ~mod(lenDash, 2)
+    lenDash = lenDash + 1;
+  end
   for i = 1:lenDash
     dash = strcat(dash, '—');
   end

modules/control_system/functions/@tf/subsasgn.m

@@ -36,13 +36,21 @@
   %=============================================================================
 function objOut = updateNumerator(objIn, value)
   st = struct(objIn);
-  st.Numerator = value;
+  if ~iscell(value)
+    st.Numerator = {value};
+  else
+    st.Numerator = value;
+  end
   objOut = class(st, 'tf');
 end
 %=============================================================================
 function objOut = updateDenominator(objIn, value)
   st = struct(objIn);
-  st.Denominator = value;
+  if ~iscell(value)
+    st.Denominator = {value};
+  else
+    st.Denominator = value;
+  end
   objOut = class(st, 'tf');
 end
 %=============================================================================

modules/control_system/tests/test_tf.m

@@ -14,9 +14,9 @@
 REF =  ' 
 sys =
  
-         2 s
-  —————————————————
-   4 s^3 + 3 s - 1
+        2 s
+  ———————————————
+  4 s^3 + 3 s - 1
  
 Continuous-time transfer function.
  
@@ -31,9 +31,9 @@
 REF =  ' 
 sys =
  
-         2 z
-  —————————————————
-   4 z^3 + 3 z - 1
+        2 z
+  ———————————————
+  4 z^3 + 3 z - 1
  
 Sample time: 1.5000 seconds
 Discrete-time transfer function.
@@ -49,14 +49,14 @@
 sys =
  
   From input 1 to output:
-         2 s
-  —————————————————
-   4 s^3 + 3 s - 1
+        2 s
+  ———————————————
+  4 s^3 + 3 s - 1
  
   From input 2 to output:
-       s + 3
-  ———————————————
-   s^2 + 3 s + 5
+      s + 3
+  —————————————
+  s^2 + 3 s + 5
  
 Continuous-time transfer function.
  
@@ -78,32 +78,32 @@
 sys =
  
   From input 1 to output:
-  1:   1
+  1:  1
  
-  2:   5
+  2:  5
  
-  3:   8
+  3:  8
  
   From input 2 to output:
-  1:   2
+  1:  2
  
-  2:   6
+  2:  6
  
-  3:   9
+  3:  9
  
   From input 3 to output:
-  1:   3
+  1:  3
  
-  2:   7
+  2:  7
  
-  3:   10
+  3:  10
  
   From input 4 to output:
-  1:   4
+  1:  4
  
-  2:   8
+  2:  8
  
-  3:   11
+  3:  11
  
      Static gain.
  
@@ -116,11 +116,11 @@
 sys = tf(num, den, Ts);
 sys.Variable = 'z^-1';
 R = evalc('display(sys)');
-REF =  ' 
+REF =   ' 
 sys =
  
    3 z^-1 + 4 z^-2
-  ——————————————————
+  —————————————————
   3 + z^-1 + 5 z^-2
  
 Sample time: 0.2000 seconds
@@ -138,14 +138,14 @@
 REF = ' 
 sys =
  
-   - 1 + 3 z^-1 - 4 z^-2
-  ———————————————————————
-   - 1 + 5 z^-1 - 7 z^-2
+  - 1 + 3 z^-1 - 4 z^-2
+  —————————————————————
+  - 1 + 5 z^-1 - 7 z^-2
  
 Sample time: 0.2000 seconds
 Discrete-time transfer function.
  
-';
+' ;
 assert_isequal(R, REF);
 %=============================================================================
 sys1 = tf([1 -1],[1 1]);
@@ -156,14 +156,14 @@
 sys =
  
   1:
-    s - 1
-  ————————
-    s + 1
+   s - 1
+  ———————
+   s + 1
  
   2:
-       s + 2
-  ———————————————
-   s^2 + 4 s + 5
+      s + 2
+  —————————————
+  s^2 + 4 s + 5
  
 Continuous-time transfer function.
  
@@ -178,14 +178,14 @@
 sys =
  
   From input 1 to output:
-    s - 1
-  ————————
-    s + 1
+   s - 1
+  ———————
+   s + 1
  
   From input 2 to output:
-       s + 2
-  ———————————————
-   s^2 + 4 s + 5
+      s + 2
+  —————————————
+  s^2 + 4 s + 5
  
 Continuous-time transfer function.
  

modules/string/functions/@cell/strjust.m

@@ -0,0 +1,35 @@
+%=============================================================================
+% Copyright (c) 2016-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 = strjust(varargin)
+  narginchk(1, 2);
+  nargoutchk(0, 1);
+
+  if nargin == 1
+    justify = 'right'; 
+  else
+    justify = lower(varargin{2});
+  end
+  mustBeMember(justify, ["left", "right", "center"], 2);
+
+  str = varargin{1};
+  if ~iscellstr(str)
+    error(_('String, cell of chars or characters vector expected.'));
+  end
+  result = str;
+  for k = 1:numel(str)
+    if ischar(str{k})
+      result{k} = strjust(str{k}, justify);
+    else
+      error(_('String, cell of chars or characters vector expected.'));
+    end
+  end
+  varargout{1} = result;
+end
+%=============================================================================

modules/string/functions/@string/strjust.m

@@ -0,0 +1,32 @@
+%=============================================================================
+% Copyright (c) 2016-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 = strjust(varargin)
+  narginchk(1, 2);
+  nargoutchk(0, 1);
+
+  if nargin == 1
+    justify = 'right'; 
+  else
+    justify = lower(varargin{2});
+  end
+  mustBeMember(justify, ["left", "right", "center"], 2);
+
+  str = varargin{1};
+  result = str;
+  for k = 1:numel(str)
+    if ischar(str{k})
+      result{k} = strjust(str{k}, justify);
+    else
+      error(_('String, cell of chars or characters vector expected.'));
+    end
+  end
+  varargout{1} = result;
+end
+%=============================================================================