Mercurial > hg > octave-lyh
view scripts/strings/str2double.m @ 5184:d35c5104ffbe
[project @ 2005-03-03 06:37:19 by jwe]
author | jwe |
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date | Thu, 03 Mar 2005 06:37:19 +0000 |
parents | cfd451656707 |
children | 75a442ecd410 |
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function [num,status,strarray] = str2double(s,cdelim,rdelim,ddelim) ## STR2DOUBLE converts strings into numeric values ## [NUM, STATUS,STRARRAY] = STR2DOUBLE(STR) ## ## STR2DOUBLE can replace STR2NUM, but avoids the insecure use of EVAL ## on unknown data [1]. ## ## STR can be the form '[+-]d[.]dd[[eE][+-]ddd]' ## d can be any of digit from 0 to 9, [] indicate optional elements ## NUM is the corresponding numeric value. ## if the conversion fails, status is -1 and NUM is NaN. ## STATUS = 0: conversion was successful ## STATUS = -1: couldnot convert string into numeric value ## STRARRAY is a cell array of strings. ## ## Elements which are not defined or not valid return NaN and ## the STATUS becomes -1 ## STR can be also a character array or a cell array of strings. ## Then, NUM and STATUS return matrices of appropriate size. ## ## STR can also contain multiple elements. ## default row-delimiters are: ## NEWLINE, CARRIAGE RETURN and SEMICOLON i.e. ASCII 10, 13 and 59. ## default column-delimiters are: ## TAB, SPACE and COMMA i.e. ASCII 9, 32, and 44. ## default decimal delimiter is '.' char(46), sometimes (e.g in ## Tab-delimited text files generated by Excel export in Europe) ## might used ',' as decimal delimiter. ## ## [NUM, STATUS] = STR2DOUBLE(STR,CDELIM,RDELIM,DDELIM) ## CDELIM .. [OPTIONAL] user-specified column delimiter ## RDELIM .. [OPTIONAL] user-specified row delimiter ## DDELIM .. [OPTIONAL] user-specified decimal delimiter ## CDELIM, RDELIM and DDELIM must contain only ## NULL, NEWLINE, CARRIAGE RETURN, SEMICOLON, COLON, SLASH, TAB, SPACE, COMMA, or ()[]{} ## i.e. ASCII 0,9,10,11,12,13,14,32,33,34,40,41,44,47,58,59,91,93,123,124,125 ## ## Examples: ## str2double('-.1e-5') ## ans = -1.0000e-006 ## ## str2double('.314e1, 44.44e-1, .7; -1e+1') ## ans = ## 3.1400 4.4440 0.7000 ## -10.0000 NaN NaN ## ## line ='200,300,400,NaN,-inf,cd,yes,no,999,maybe,NaN'; ## [x,status]=str2double(line) ## x = ## 200 300 400 NaN -Inf NaN NaN NaN 999 NaN NaN ## status = ## 0 0 0 0 0 -1 -1 -1 0 -1 0 ## ## Reference(s): ## [1] David A. Wheeler, Secure Programming for Linux and Unix HOWTO. ## http://en.tldp.org/HOWTO/Secure-Programs-HOWTO/ ## This program is free software; you can redistribute it and/or ## modify it under the terms of the GNU General Public License ## as published by the Free Software Foundation; either version 2 ## of the License, or (at your option) any later version. ## ## This program is distributed in the hope that it will be useful, ## but WITHOUT ANY WARRANTY; without even the implied warranty of ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ## GNU General Public License for more details. ## ## You should have received a copy of the GNU General Public License ## along with this program; if not, write to the Free Software ## Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. ## $Revision: 1.11 $ ## $Id: str2double.m,v 1.11 2004/06/23 20:52:32 schloegl Exp $ ## Copyright (C) 2004 by Alois Schloegl <a.schloegl@ieee.org> ## This function is part of Octave-Forge http://octave.sourceforge.net/ FLAG_OCTAVE = exist('OCTAVE_VERSION','builtin'); ## valid_char = '0123456789eE+-.nNaAiIfF'; % digits, sign, exponent,NaN,Inf valid_delim = char(sort([0,9:14,32:34,abs('()[]{},;:"|/')])); % valid delimiter if nargin < 1, error('missing input argument.') end if nargin < 2, cdelim = char([9,32,abs(',')]); % column delimiter else % make unique cdelim cdelim = char(sort(cdelim(:))); tmp = [1;1+find(diff(abs(cdelim))>0)]; cdelim = cdelim(tmp)'; end if nargin < 3, rdelim = char([0,10,13,abs(';')]); % row delimiter else % make unique rdelim rdelim = char(sort(rdelim(:))); tmp = [1;1+find(diff(abs(rdelim))>0)]; rdelim = rdelim(tmp)'; end if nargin<4, ddelim = '.'; elseif length(ddelim)~=1, error('decimal delimiter must be exactly one character.'); end % check if RDELIM and CDELIM are distinct delim = sort(abs([cdelim,rdelim,ddelim])); tmp = [1, 1 + find(diff(delim)>0)]; delim = delim(tmp); %[length(delim),length(cdelim),length(rdelim)] if length(delim) < (length(cdelim)+length(rdelim))+1, % length(ddelim) must be one. error('row, column and decimal delimiter are not distinct.'); end % check if delimiters are valid tmp = sort(abs([cdelim,rdelim])); flag = zeros(size(tmp)); k1 = 1; k2 = 1; while (k1 <= length(tmp)) & (k2 <= length(valid_delim)), if tmp(k1) == valid_delim(k2), flag(k1) = 1; k1 = k1 + 1; elseif tmp(k1) < valid_delim(k2), k1 = k1 + 1; elseif tmp(k1) > valid_delim(k2), k2 = k2 + 1; end end if ~all(flag), error('Invalid delimiters!'); end ####% various input parameters if isnumeric(s) if all(s<256) & all(s>=0) s = char(s); else error('STR2DOUBLE: input variable must be a string') end end if isempty(s), num = []; status = 0; return; elseif iscell(s), strarray = s; elseif ischar(s) & all(size(s)>1), ## char array transformed into a string. for k = 1:size(s,1), tmp = find(~isspace(s(k,:))); strarray{k,1} = s(k,min(tmp):max(tmp)); end elseif ischar(s), num = []; status = 0; strarray = {}; s(end+1) = rdelim(1); % add stop sign; makes sure last digit is not skipped RD = zeros(size(s)); for k = 1:length(rdelim), RD = RD | (s==rdelim(k)); end CD = RD; for k = 1:length(cdelim), CD = CD | (s==cdelim(k)); end k1 = 1; % current row k2 = 0; % current column k3 = 0; % current element sl = length(s); ix = 1; %while (ix < sl) & any(abs(s(ix))==[rdelim,cdelim]), while (ix < sl) & CD(ix), ix = ix + 1; end ta = ix; te = []; while ix <= sl; if (ix == sl), te = sl; end %if any(abs(s(ix))==[cdelim(1),rdelim(1)]), if CD(ix), te = ix - 1; end if ~isempty(te), k2 = k2 + 1; k3 = k3 + 1; strarray{k1,k2} = s(ta:te); %strarray{k1,k2} = [ta,te]; flag = 0; %while any(abs(s(ix))==[cdelim(1),rdelim(1)]) & (ix < sl), while CD(ix) & (ix < sl), flag = flag | RD(ix); ix = ix + 1; end if flag, k2 = 0; k1 = k1 + 1; end ta = ix; te = []; end ix = ix + 1; end else error('STR2DOUBLE: invalid input argument'); end [nr,nc]= size(strarray); status = zeros(nr,nc); num = repmat(NaN,nr,nc); for k1 = 1:nr, for k2 = 1:nc, t = strarray{k1,k2}; if (length(t)==0), status(k1,k2) = -1; ## return error code num(k1,k2) = NaN; else ## get mantisse g = 0; v = 1; if t(1)=='-', v = -1; l = min(2,length(t)); elseif t(1)=='+', l = min(2,length(t)); else l = 1; end if strcmpi(t(l:end),'inf') num(k1,k2) = v*inf; elseif strcmpi(t(l:end),'NaN'); num(k1,k2) = NaN; else if ddelim=='.', t(t==ddelim)='.'; end if FLAG_OCTAVE, [v,tmp2,c] = sscanf(char(t),'%f %s','C'); else [v,c,em,ni] = sscanf(char(t),'%f %s'); c = c * (ni>length(t)); end if (c==1), num(k1,k2) = v; else num(k1,k2) = NaN; status(k1,k2) = -1; end end end end end