Read a string with numbers and scientific notations

4 次查看（过去 30 天）
BRC
BRC 2017-7-4
评论： Walter Roberson 2017-7-4
Dear All,
I am trying to read a text file looks like this:
# Counters
sec=60, Monitor=8.66289e+06, bstop=818664, I0=829726, I1=0, ch5=0, ch6=0, ch7=0.
I would like to read the Monitor value (8.66289e+06). I was using
k=sprintf('txt_files/MnO2_20170512_05120943_%04d.txt',i);
filetext=fileread(k);
numbers = str2double(regexp(filetext, '(?<=Monitor=[^0-9]*)[0-9]*\.?[0-9]+', 'match'));
In this way I can get the number "8.66289". But today I would like to include the scientific notation as well. So my output will be "8.66289e+06". I am not really sure how to proceed with this even though I searched in the forum.
I tried
numbers3 = regexp(filetext, '(?<== )((\d|(+)|(\.)|(e))+','match');
and
numbers3=sscanf(sprintf('%s ',numbers3{:}),'%g')
But looks like something was not right in my code.
Thank you for help!

请先登录，再回答此问题。

采纳的回答

Walter Roberson
Walter Roberson 2017-7-4
S = 'sec=60, Monitor=8.66289e+06, bstop=818664, I0=829726, I1=0, ch5=0, ch6=0, ch7=0.';
result = regexp(S, '(?<name>\w+)=(?<value>[^,]+)', 'names');
>> result(2)
ans =
struct with fields:
name: 'Monitor'
value: '8.66289e+06'
  3 个评论
显示 1更早的评论
BRC
BRC 2017-7-4
I tried
numbers= regexp(filetext, '(?<name>\w+)=(?<value>[^,]+)', 'names');
a=numbers(2);
c = struct2cell(a);
m(i)=c(2)
but the error message was
The following error occurred converting from cell
to double:
Error using double
Conversion to double from cell is not possible.
Walter Roberson
Walter Roberson 2017-7-4
all_values_as_numeric = str2double( {result.value} );
Note: if you can count on the order being the same each time, then
S = 'sec=60, Monitor=8.66289e+06, bstop=818664, I0=829726, I1=0, ch5=0, ch6=0, ch7=0.';
result = regexp(S, '(?<==)([^,]+)', 'match');
all_values_as_numeric = str2double(result);

请先登录，再进行评论。

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Characters and Strings 的更多信息

标签

产品

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by