Replacing commas with whitespaces using regexprep

Hello,

i am new to Matlab and really struggling with the regexprep function. I try to replace commas in brackets with whitespaces, so i can use the split function, without splitting my data in brackets.

Task:

str= '(asdf,(50,51,52),jklö)'

str_desired='(asdf,(50 51 52),jklö)'

I already found this:

exp='(?<=\()[^)]*(?=\))'

rep=' '

newstr=regexprep(str,exp,rep)= '( ),jklö)'+

But its not quite doing what i want, and i cant figure out how to place the hexadecimalvalue '\x2C' for comma.

Thank you very much!

Answer 1

[Stephen23]

>> str = '(asdf,(50,51,52),jkl)';
>> regexprep(str,'(\d+),(\d+),(\d+)','$1 $2 $3')
ans = (asdf,(50 51 52),jkl)

If you are already using regexprep I don't see the point in using strsplit as well, you might as well just use regexp to split the string up.

[Raymond Wollenberg]

Hello Stephen,

thank you very much for your fast answer. I am sorry i have to specify my problem a little bit better. My example was just to bad :(

My data looks more like this:

('1ywu2rkZn3CfItlgI791$i',#41,'Pset_WindowCommon',$,(#279,#2098,#2099))

('1jPCssxb5C1RSM_YLIx$zl',#41,$,$,(#854,#889,#924,#1062,#1096,#1130,#1275,#2812,#2833),#135)

So the amount of arguments is totally variable. I have to split for every "field" which are divided by commas. So data in brackets belongs to only one field. Thats why i tried to work this code example:

exp=(?<=\() [^)]* (?=\)) [Look behind "(" , every character which is not ")" , look before ")"]

But i couldnt figure out how i can replace the middle ("*") with the indicator for commas. So only commas in brackets get replaced.

Thank you in advance, cheers!

[Stephen23]

@Raymond Wollenberg: please upload some sample data in a .mat file, by clicking the paperclip button. Or the original data source file.

[Raymond Wollenberg]

source file

[Stephen23]

This should get you started. Note that for simplicity I excluded the leading/trailing parentheses from each string (you can do this trivially using indexing).

>> R = '(\(?)(?(1)[^\)]+\)|[^,]+)'; % regular expression.
>> S = '''1ywu2rkZn3CfItlgI791$i'',#41,''Pset_WindowCommon'',$,(#279,#2098,#2099)';
>> D = regexp(S,R,'match');
>> D{:}
ans =
'1ywu2rkZn3CfItlgI791$i'
ans =
#41
ans =
'Pset_WindowCommon'
ans =
$
ans =
(#279,#2098,#2099)
>> S = '''1jPCssxb5C1RSM_YLIx$zl'',#41,$,$,(#854,#889,#924,#1062,#1096,#1130,#1275,#2812,#2833),#135';
>> D = regexp(S,R,'match');
>> D{:}
ans =
'1jPCssxb5C1RSM_YLIx$zl'
ans =
#41
ans =
$
ans =
$
ans =
(#854,#889,#924,#1062,#1096,#1130,#1275,#2812,#2833)
ans =
#135

It uses a conditional operator to change the match expresssion, depending on whether an opening parenthesis was matched at the start of the field.

https://www.mathworks.com/help/matlab/matlab_prog/regular-expressions.html#bqv21pe-1

You might also be interested to download my interactive regular expression tool, which lets you quickly test and develop regular expressions:

https://www.mathworks.com/matlabcentral/fileexchange/48930-interactive-regular-expression-tool

[Raymond Wollenberg]

Thank you very much again!

I already installed your tool on midday :D in hope I can use my problem with it. Thanks for explanation, i will dig into it tomorrow!

[Raymond Wollenberg]

Worked out perfect, thank you!