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function t = subsasgnDot(t,s,b,deleting)
%SUBSASGNDOT Subscripted assignment to a table.
% Copyright 2012-2016 The MathWorks, Inc.
% '.' is assignment to or into a variable. Any sort of subscripting
% may follow that, and row labels are inherited from the table.
import matlab.internal.tableUtils.emptyLike
import matlab.internal.datatypes.isCharString
import matlab.internal.datatypes.istabular
import matlab.internal.tableUtils.isScalarInt
subsType = matlab.internal.table.tableDimension.subsType; % "import" for calls to subs2inds
if ~isstruct(s), s = struct('type','.','subs',s); end
% For built-in tyes, s(2).type=='()' guarantees that length(s)==2, but for a var that
% is itself a table, parens need not be the end. deletion other than t.Var or t.Var(...)
% is handled by the assignment code path.
if nargin < 4
deleting = isnumeric(b) && builtin('_isEmptySqrBrktLiteral',b) ...
&& (isscalar(s) || ((length(s) == 2) && isequal(s(2).type,'()')));
end
t_nrows = t.rowDim.length;
t_nvars = t.varDim.length;
% Translate variable (column) name into an index. Avoid overhead of
% t.varDim.subs2inds as much as possible in this simple case.
varName = s(1).subs;
if isnumeric(varName)
% Allow t.(i) where i is an integer
varIndex = varName;
if ~isScalarInt(varName,1)
error(message('MATLAB:table:IllegalVarIndex'));
end
isNewVar = (varIndex > t_nvars);
if isNewVar
if deleting
error(message('MATLAB:table:VarIndexOutOfRange'));
elseif varIndex > t_nvars+1
error(message('MATLAB:table:DiscontiguousVars'));
else
[~,~,~,~,updatedVarDim] = t.varDim.subs2inds(varIndex,subsType.assignment);
varName = updatedVarDim.labels{varIndex};
end
end
elseif ischar(varName) && (isrow(varName) || isequal(varName,'')) % isCharString(varName)
varIndex = find(strcmp(varName,t.varDim.labels));
isNewVar = false; % assume for now, update below
if isempty(varIndex)
% Check against reserved names first as a failsafe against shadowing
% .Properties by a dimension name.
if ~deleting && matlab.internal.table.checkReservedNames(varName,'varnames') % one name, don't need to wrap with any()
% Handle assignment to a property under the 'Properties' (virtual)
% property, or to the entire 'Properties' property.
if strcmp(varName,'Properties')
try
if isscalar(s)
t = setProperties(t,b);
else
t = setProperty(t,s(2:end),b);
end
catch ME
if ~isscalar(s) && strcmp(ME.identifier,'MATLAB:table:UnknownProperty')
propName = s(2).subs;
match = find(strcmpi(propName,t.propertyNames),1);
if ~isempty(match) % a property name. but with wrong case
match = t.propertyNames{match};
error(message('MATLAB:table:UnknownPropertyCase',propName,match));
else
throw(ME);
end
else
throw(ME);
end
end
return
else % t.VariableNames or t.RowNames
error(message('MATLAB:table:InvalidPropertyAssignment',varName,varName));
end
elseif strcmp(varName,t.metaDim.labels{1})
% If it's the row dimension name, assign to the row labels
varIndex = 0;
% For assignments onto the row labels, accept any vector. For assignments
% into, leave the RHS alone.
if isscalar(s)
if isvector(b), b = b(:); end
elseif deleting % && ~isscalar(s)
error(message('MATLAB:table:NestedSubscriptingWithDotRowsDeletion',t.metaDim.labels{1}));
end
elseif strcmp(varName,t.metaDim.labels{2})
% If it's the vars dimension name, assign to t{:,:}. Deeper subscripting
% is not supported, use explicit braces for that.
if ~isscalar(s)
error(message('MATLAB:table:NestedSubscriptingWithDotVariables',t.metaDim.labels{2}));
end
varIndex = -1;
elseif deleting
error(message('MATLAB:table:UnrecognizedVarNameDeleting',varName,varName));
else
isNewVar = true;
matlab.internal.tableUtils.makeValidName(varName,'varnamesError'); % error if invalid
% If this is a new variable, it will go at the end.
varIndex = t_nvars + 1;
updatedVarDim = t.varDim.lengthenTo(varIndex,{varName});
end
end
else
error(message('MATLAB:table:IllegalVarSubscript'));
end
% Handle empty assignment intended as deletion of an entire variable or of
% columns/pages/etc. of a variable. Deletion of rows in a (single)
% variable is caught here and not allowed. Other empty assignment
% syntaxes may be assignment to cells or may be deletion of things deeper
% in a non-atomic variable, neither is handled here.
if deleting
% Syntax: t.var = []
%
% Delete an entire variable.
if isscalar(s)
if varIndex > 0
t.data(varIndex) = [];
t.varDim = t.varDim.deleteFrom(varIndex);
elseif varIndex == 0
t.rowDim = t.rowDim.removeLabels(); % this might error
else % varindex == -1
varIndex = 1:t.varDim.length;
t.data(varIndex) = [];
t.varDim = t.varDim.deleteFrom(varIndex);
end
% Syntax: t.var(:,...) = []
% t.var(rowIndices,...) = [] is illegal
%
% Delete columns/pages/etc. of a variable, with ':' as the first index
% in subscript. This may change the dimensionality of the variable,
% but won't change the number of rows because we require ':' as the
% first index.
else % length(s) == 2
if ~iscolon(s(2).subs{1})
error(message('MATLAB:table:EmptyAssignmentToVariableRows'));
elseif isscalar(s(2).subs)
error(message('MATLAB:table:EmptyAssignmentToAllVariableElements'));
end
var_j = t.data{varIndex};
try %#ok<ALIGN>
if istabular(var_j)
var_j = subsasgnParens(var_j,s(2),[],false,true); % can't use table subscripting directly
else
var_j(s(2).subs{:}) = [];
end
catch ME, throw(ME); end
t.data{varIndex} = var_j;
end
else
% Syntax: t.var = b
%
% Replace an entire variable. It must have the right number of rows, unless
% the LHS is 0x0.
updatedRowDim = [];
if isscalar(s)
if size(b,1) ~= t_nrows && (t_nrows+t_nvars > 0)
% If the assignment has the wrong number of rows, check for some
% common mistakes to suggest what may have been intended
if strcmpi(varName,'Properties') && isstruct(b) && isscalar(b)
% Things like t.properties = scalarStruct
str = getString(message('MATLAB:table:IntendedPropertiesAssignment'));
error(message('MATLAB:table:RowDimensionMismatchSuggest',str));
else
match = find(strcmpi(varName,t.propertyNames),1);
if ~isempty(match)
% Things like t.PropertyName = ...
match = t.propertyNames{match};
str = getString(message('MATLAB:table:IntendedPropertyAssignment',match,match));
error(message('MATLAB:table:RowDimensionMismatchSuggest',str));
end
end
% Anything else, no suggestion. No point in checking for a case
% insensitive match to an existing var, even with the correct case,
% this would still be an illegal assignment
error(message('MATLAB:table:RowDimensionMismatch'));
end
var_j = b;
% Syntax: t.var(rowIndices,...) = b
% t.var{rowIndices,...} = b
% t.var{rowIndices,...} = [] (this is assignment, not deletion)
% t.var.field = b
%
% Assign to elements in a variable. Assignment can also be used to
% expand the variable's number of rows, or along another dimension.
%
% Cell indexing, e.g. t.var{rowIndices,...}, or a reference to a
% field, e.g. t.var.field, may also be followed by deeper levels of
% subscripting. Cannot create a new var implicitly by deeper indexing.
else % ~isscalar(s)
if isNewVar && (length(s) > 2) && ~isequal(s(2).type,'.')
% If the assignment is not to an existing var, check for some common
% mistakes to suggest what may have been intended
match = find(strcmpi(varName,t.varDim.labels),1);
if ~isempty(match)
% An existing variable name, but with wrong case
match = t.varDim.labels{match};
str = getString(message('MATLAB:table:IntendedVarAssignment',match));
error(message('MATLAB:table:InvalidExpansionDotDepthSuggest',str));
end
% Anything else, no suggestion
error(message('MATLAB:table:InvalidExpansionDotDepth'));
end
if isequal(s(2).type,'.') % dot indexing into variable
% If the assignment is not to an existing var, check for some common
% mistakes to suggest what may have been intended
if isNewVar
if strcmpi(varName,'Properties') && isCharString(s(2).subs)
% Things like t.properties.name
str = getString(message('MATLAB:table:IntendedPropertiesAssignment'));
error(message('MATLAB:table:InvalidExpansionDotSuggest',str));
else
match = find(strcmpi(varName,t.varDim.labels),1);
if ~isempty(match)
% An existing variable name, but with wrong case
match = t.varDim.labels{match};
str = getString(message('MATLAB:table:IntendedVarAssignment',match));
error(message('MATLAB:table:InvalidExpansionDotSuggest',str));
else
% Anything else, no suggestion
error(message('MATLAB:table:InvalidExpansionDot'));
end
end
end
if varIndex > 0
var_j = t.data{varIndex};
elseif varIndex == 0
var_j = t.rowDim.labels;
else % varIndex == -1
assert(false);
end
else % () or {} subscripting into variable
% Initialize a new var, or extract an existing var.
if isNewVar
% Start the new var out as an empty of b's class with
% the same number of rows as the table.
var_j = emptyLike([t_nrows,0],'Like',b);
else
if varIndex > 0
var_j = t.data{varIndex};
elseif varIndex == 0
var_j = t.rowDim.labels;
else % varIndex == -1
assert(false);
end
end
% The variable inherits row labels from the table. Translate labels to
% row numbers if necessary.
rowIndices = s(2).subs{1};
if isnumeric(rowIndices) || islogical(rowIndices) || iscolon(rowIndices)
% Can leave these alone to save overhead of calling subs2inds
else
% Row labels may be used as a "linear index" only if the variable
% has a single column.
if ~iscolumn(var_j) && isscalar(s(2).subs)
error(message('MATLAB:table:InvalidLinearIndexing'));
end
end
% subs2inds returns the indices as a col vector, which prevents reshaping.
% This is fine because the var is constrained inside the table.
[rowIndices,~,~,~,updatedRowDim] = t.rowDim.subs2inds(rowIndices,subsType.assignment);
s(2).subs{1} = rowIndices;
end
% Now let the variable's subsasgn handle the subscripting in
% things like t.name(...) or t.name{...} or t.name.attribute
% Calling subsasgn directly allows changing the shape of var_j by
% assignment, which the interpreter would not allow.
if length(s) == 2
if isobject(var_j)
% If b is superior to var_j, this will dispatch to b
try %#ok<ALIGN>
var_j = subsasgn(var_j,s(2),b);
catch ME, throw(ME); end
else
% Call builtin, to get correct dispatching even if b is an object.
try %#ok<ALIGN>
var_j = builtin('subsasgn',var_j,s(2),b);
catch ME, throw(ME); end
end
else % length(s) > 2
% Trick the third and higher levels of subscripting in things like
% t.Var{i}(...) etc. into dispatching to the right place even when
% t.Var{i}, or something further down the chain, is itself a table.
try %#ok<ALIGN>
var_j = matlab.internal.table.subsasgnRecurser(var_j,s(2:end),b);
catch ME, rethrow(ME); end % point to the line in subsasgnRecurser
end
end
% If this is a new variable, make it official.
if isNewVar
t.varDim = updatedVarDim;
end
% If an entire var was replaced or created, the new value was required to
% have the same number of rows as the table. However, when assigning into a
% new var, the assignment might create something shorter than the table, so
% check for that and lengthen the new var to match the table. In most
% cases, assigning into an existing var leaves it as the correct height,
% although in at least one oddball case (assigning a field to a non-struct),
% assigning into an existing var can make the result shorter then it was
% originally, so check for those too.
varLen = size(var_j,1);
if varLen < t_nrows % t's original number of rows
warning(message('MATLAB:table:RowsAddedNewVars'));
var_j = matlab.internal.table.lengthenVar(var_j,t_nrows);
end
if varIndex > 0
t.data{varIndex} = var_j;
elseif varIndex == 0
t.rowDim = t.rowDim.setLabels(var_j);
else % varIndex == -1
t = subsasgnBraces(t,{':' ':'},var_j);
end
% If the var being assigned to is now taller than the table, add rows to
% the rest of the table, including row labels. This might be because the
% assignment lengthened an existing var, or because an "into" assignment
% created a new var taller than the table. Warn only if we have to lengthen
% existing vars that have not been assigned to -- if there's currently only
% one var in the table (which might be existing or new), don't warn about
% any default values "filled in in the middle".
if varLen > t_nrows % t's original number of rows
if t.varDim.length > 1 % some existing vars were not assigned to
warning(message('MATLAB:table:RowsAddedExistingVars'));
end
if isempty(updatedRowDim)
t.rowDim = t.rowDim.lengthenTo(varLen);
else
t.rowDim = updatedRowDim;
end
t = lengthenTableVars(t,varLen); % updates nrows
end
end