s_header.asv

matlab源代码

z0function seismic=s_header(seismic,action,mnem,values,units,description)
% Function manipulates header(s) of a seismic structure
% Written by E. R.; Date March 16, 2000
% Last updated; June 30, 2001: make "units" and "description" optional if 
%                              action is 'replace'
%
%          seismic=s_header(seismic,action,mnem,values,units,description)              
% INPUT
% seismic      Seismic structure;
%              If this is the only input argument, "action" is set to 'slist' and "mnem' is
%              set to '*'. The function prints a list of all header values as describend 
%              below. 
% action       Defines action to take. Possible values are:
%              'add'      Add header with mnemonic mnem. Gives error message if 
%                         header already exists
%              'add_ne'   Add header with mnemonic mnem. Replaces it if it already exists.
%              'replace'  Replaces header with mnemonic mnem; error if
%                         header does not exist
%              'delete'   Delete header(s) with mnemonic(s) mnem; 
%                         error if header does not exist 
%              'delete_ne' Delete header(s) with mnemonic(s) mnem if the header is present
%                         no error if one or more of the header(s) specified does not exist 
%              'keep'     Keep header(s) with mnemonic(s) mnem and deletes all others;
%                         error if one or more of the header(s) do not exist 
%              'keep_ne'  Keep header(s) with mnemonic(s) mnem if it is (they are) present
%                         and deletes all others; no error if any or all headers specified 
%                         are not present
%              'rename'   Rename header mnemonic, keep everything else the same
%              'list'    Print short list: for specified header mnemonic(s) it lists minimum 
%                         and maximum value, smallest and greatest trace-to-trace change,
%                         units of measurement, and header description
%              
%          The other input parameters depend on the parameter "action"
%
%                   CASE action = 'add', 'add_ne', or 'replace'
% mnem         Header mnemonic
% values       Header values; if only one value is given the header is assumed 
%              to be constant
% units        Units of measurement for curve values (optional if 'action' is 
%              'replace')
% description  Description of curve mnemonic (optional if 'action' is 'replace')
%              If "action" is 'replace' "units" and "description" need not be given; 
%              in this case the original "units" and "description" are retained.
%
%                  CASE action = 'delete', delete_ne', 'keep', 'keep_ne', or 'list'
% mnem         Header mnemonic or cells array with header mnemonics
%              '*' means all headers
%
%                  CASE action = 'rename'
% mnem         Cell array consisting of two strings: the old and 
%              the new name of the header
%
% OUTPUT
% seismic      "Updated" seismic structure (no output if action == 'list')
%
%                  seismic=s_header(seismic,action,mnem,values,units,description)
%                  seismic=s_header(seismic,action,mnem)   for action=delete,delete_ne,keep,keep_ne,list
%                  seismic=l_header(seismic)               assumes action list

global S4M

if nargin < 1
  error('At least one input argument (seismic structure) required')
end

if ~isstruct(seismic)
  error('The first input argument must be a seismic structure')
end
% seismic=s_new2compact(seismic);    % Convert to compact header format

if nargin == 1
  action='list';
  mnem={'*'};
else
  action=lower(action);
  if ~iscell(mnem)
    mnem={mnem};
  end
end

if ~isfield(seismic,'headers') 
  if ~strcmp(action,'add') & ~strcmp(action,'add_ne')
    disp('Seismic structure has no headers')
    if nargout == 0
       clear seismic; 
%    else
%       seismic=s_compact2new(seismic);    % Convert to new header format
    end
    return
  else
    nh=0;
    mh=size(seismic.traces,2);
  end
else
  [nh,mh]=size(seismic.headers);
end

if isfield(seismic,'history') & S4M.history
  seismic=s_history(seismic,'append',[char(action),': ',cell2str(mnem,', ')]);
end

lmnem=length(mnem);
if lmnem == 1 & strcmp(char(mnem),'*') & ...
   ~strcmp(action,'add') & ~strcmp(action,'add_ne') & ~strcmp(action,'replace')
  mnem=seismic.header_info(:,1);
  lmnem=length(mnem);
end

switch action
               case {'add','add_ne','replace'}

lv=length(values);
if lv == 1
  val=values; 
elseif lv == mh
  val=reshape(values,1,mh);
else
  error(['Input argument "values" must be a constant or a vector ', ...
         'whose length is equal to the number of traces in the seismic structure'])
end

if ~isfield(seismic,'header_info')
   idx=[];
else
   [idx,ierr]=header_index1(seismic,mnem);
%   idx=find(ismember(lower(seismic.header_info(:,1)),mnem));
end

if ~isempty(idx)
   if strcmpi(action,'add')
      error(['The header mnemonic ',char(mnem),' already exists in the header'])
   else
     seismic.headers(idx,:)=val;
     if nargin > 4
       seismic.header_info{idx,2}=units;
       if nargin > 5
         seismic.header_info{idx,3}=description;
       end
     end
   end
else
  if strcmpi(action,'replace')
    error(['The header mnemonic ',char(mnem),' does not exist in the header'])
  else
    idx=nh+1;
    seismic.header_info(idx,1)=mnem;
    seismic.headers(idx,1:mh)=val;
    seismic.header_info{idx,2}=units;
    seismic.header_info{idx,3}=description;
  end      
end

              case {'delete','delete_ne'}
idx=find(ismember(lower(seismic.header_info(:,1)),mnem));
if lmnem ~= length(idx) & strcmp(action,'delete')
  for ii=1:lmnem
    if ~ismember(lower(seismic.header_info(:,1)),mnem(ii))
      disp(['Header ',char(mnem(ii)),' not present'])
    end
  end
  error('Abnormal termination')
end
if length(idx) == length(seismic.header_info(:,1))
%  seismic=rmfield(seismic,{'headers','header_mnem','header_units','header_descriptions'});
  seismic=rmfield(seismic,{'headers','header_info'});
else
  seismic.headers(idx,:)=[];
  seismic.header_info(idx,:)=[];
end 

              case {'keep','keep_ne'}
idx=find(~ismember(seismic.header_info(:,1),mnem));
if lmnem ~= nh-length(idx) & strcmp(action,'keep')
  for ii=1:lmnem
    if ~ismember(lower(seismic.header_info(:,1)),mnem(ii))
      disp(['Header ',char(mnem(ii)),' not present'])
    end
  end
  error(' Abnormal termination')
end
if length(idx) == nh
  seismic=rmfield(seismic,{'headers','header_info'});
else
  seismic.headers(idx,:)=[];
  seismic.header_info(idx,:)=[];
end 

              case 'rename'
if lmnem ~= 2
  error(['Parameter mnem must be a cell array with two strings' , ... 
        '(old header mnemonic and new header mnemonic)'])
elseif ismember(seismic.header_info(:,1),mnem(2))
  error(['New header mnemonic ',char(mnem(2)),' already exists in the header'])
else
  idx=find(ismember(seismic.header_info(:,1),mnem(1)));
  if isempty(idx)
    error(['Seismic header ',char(mnem(1)),' does not exist'])
  else
    seismic.header_info(idx,1)=mnem(2);
  end
end

              case 'list'
idx=find(ismember(seismic.header_info(:,1),mnem));
if isempty(idx)
  error([' Header(s) "',cell2str(mnem,'", "'),'" do(es) not exist'])
end
mnems=char('MNEMONIC',seismic.header_info{idx,1});
descr=char('DESCRIPTION',seismic.header_info{idx,3});
units=char('UNITS',seismic.header_info{idx,2});
hmin=min(seismic.headers(idx,:),[],2);
hmax=max(seismic.headers(idx,:),[],2);
dh=diff(seismic.headers(idx,:),[],2);
dhmin=min(dh,[],2);
dhmax=max(dh,[],2);
spaces(1:length(hmax)+1)=' ';

if isempty(dhmin)     % handle case of only one input trace (no trace-to-trace change)
  dhmin=' n/a';
  sdhmin=char('MIN_STEP',dhmin(ones(length(hmin),1),:));
  sdhmax=char('MAX_STEP',dhmin(ones(length(hmin),1),:));
else
  sdhmin=char('MIN_STEP',num2str(dhmin));
  sdhmax=char('MAX_STEP',num2str(dhmax));
end

shmin=char('MIN_VAL',num2str(hmin));
shmax=char('MAX_VAL',num2str(hmax));
disp(['Headers of seismic data set "',seismic.name,'"'])
disp([mnems,spaces',shmin,spaces',spaces',shmax,spaces', ...
      spaces',sdhmin,spaces',spaces',sdhmax,spaces',units,spaces',descr]);

%   Write message if one or more of the headers specified were not found
if lmnem ~= length(idx)    
  for ii=1:lmnem
    if ~ismember(lower(seismic.header_info(:,1)),mnem(ii))
      disp([char(mnem(ii)),' is not present'])
    end
  end
end


              otherwise
error(['Action ',action,' not defined'])

end	      % End of switch block

if nargout == 0
   clear seismic;
%else
%   seismic=s_compact2new(seismic);   % Convert to new header format
end