Saving a variable to a continuously changing file name

I would like to save a variable to a file/filename that relates to a previously loaded filename and repeat the code with a new file and save the variable to a different filename.

First I load in a file of choice

data = uigetfile('*.csv');
IP_Testing = xlsread(data)

example: BurnIn_2ndary_volt_curr_columnar_20150527_1940_IAM002.csv

Note: The datetime is in the filename

Then I reduce the file to a small matrix from data that I selected with the brushing tool. I assign that matrix to a variable.

details = [mean(IAMHS(:,2)) std(IAMHS(:,2)) min(IAMHS(:,2)) max(IAMHS(:,2));...
           mean(CMP1(:,2)) std(CMP1(:,2)) min(CMP1(:,2)) max(CMP1(:,2));...
           mean(CMP2(:,2)) std(CMP2(:,2)) min(CMP2(:,2)) max(CMP2(:,2));...
           mean(PDU_OP(:,2)) std(PDU_OP(:,2)) min(PDU_OP(:,2)) max(PDU_OP(:,2));...
           mean(ThreePThreeV(:,2)) std(ThreePThreeV(:,2)) min(ThreePThreeV(:,2)) max(ThreePThreeV(:,2));...
           mean(TenV_PREF(:,2)) std(TenV_PREF(:,2)) min(TenV_PREF(:,2)) max(TenV_PREF(:,2));...
           mean(TenV_REF(:,2)) std(TenV_REF(:,2)) min(TenV_REF(:,2)) max(TenV_REF(:,2))];

Now I would like to save the matrix (details) to a file name that relates to the previous loaded file (same datetime).

Examples: BurnIn_2ndary_20150527_1940.mat

-------------------------------------------------------------------------------------------------------------

The problem is I will run my code to retrieve another file similar to the first one I imported (different datetime).

Example: BurnIn_2ndary_volt_curr_columnar_20150528_1500_IAM002.csv

In the end I would like to save it to a similar name

Examples: BurnIn_2ndary_20150528_1500.mat

So I need my code that saves the file to be able to recognize a different file so that I can save it to a different filename. Being able to hold on to the datetime in the name is important for later plotting all of the new files I have saved

Answer 1

[Walter Roberson]

You can use regexp() to extract portions of the name. For example,

regexp(filename, '\d+_\d+', 'match')

should extract the data and time substring.

The first part looks to be

regexp(filename,'^[A-Za-z0-9]+_[A-Za-z0-9]+', 'match')

[Calabrese]

When I run that code for my file it outputs

'BurnIn_2ndary'

Is there a way to skip volt, curr, and columnar in the filename

'BurnIn_2ndary_volt_curr_columnar_20150530_2200_IAM002.csv'

and continue to retrieve the numbers for the datetime?

I tried

regexp(data,'^[A-Za-z0-9]+_[A-Za-z0-9]+_[0-9]+_[0-9]+_[0-9]+_[0-9]+_[0-9]+', 'match')

First time using the command but I thought maybe searching for numbers in the names before the datetime would exclude them with that. When I ran it, I only got

{ }

[Walter Roberson]

The easiest thing is to use both calls that I show and put them together.

If you really want to do it in one unreadable call, then

regexprep(filename,{'(?<=[A-Za-z0-9]+_[A-Za-z0-9]+_).*?(?=\d+_\d+_)','_[A-Za-z0-9]+\.csv$'}, '')

[Calabrese]

I see, I didn't realize the first line of code you shared was specific for datetime. I thought it was just an example.

Now how would I save this details matrix with the preferred filename extracted (substring_datetime or BurnIn_2ndary_20150528_1500) with my details matrix? I can't have the code using one simple name because each time I run a new set of data it will need to save to a different filename

[Walter Roberson]

first_part = regexp(filename,'^[A-Za-z0-9]+_[A-Za-z0-9]+_', 'match');
second_part = regexp(filename, '\d+_\d+', 'match')
preferred_filename = [first_part second_part];
save(preferred_filename, 'details')

[Calabrese]

I had tried something similar to that and that but then I got an error each time with save

(argument must contain a string)

[Walter Roberson]

Perhaps you left out the quotes around 'details'

[Calabrese]

No they are there.. It seems like it cannot be done without the preferred_filename being in quotes which wouldn't produce the right filename of course. I would like to save it as a .mat file too. What do you think?

Error using save
Argument must contain a string.

Error in data_2ndary (line 96)
save(preferred_filename, 'details')

[Calabrese]

Walter, it seems the issue occurs because when done separately the preferred file name is a two cell matrix and cannot be a string. However using the longer code below that is a little confusing to me works by assigning it to variable, a, and then saving. Weird but I'll take it

a = regexprep(filename,{'(?<=[A-Za-z0-9]+_[A-Za-z0-9]+_).*?(?=\d+_\d+_)','_[A-Za-z0-9]+\.csv$'}, '');
save(preferred_filename, 'details')

The only issue is it outputs: BurnIn_2ndary_0150601_1600

It is missing the 2 in 20150601.

Should be: BurnIn_2ndary_20150601_1600

I was able to fix the issue by playing around and adding an underscore right before the datetime export

a = regexprep(filename,{'(?<=[A-Za-z0-9]+_[A-Za-z0-9]+_).*?_(?=\d+_\d+_)','_[A-Za-z0-9]+\.csv$'}, '');

If you don't mind explaining the unreadable call too that would be greatly appreciated. Thank you for all of your help!

[Walter Roberson]

preferred_filename = [first_part{1} second_part{1}];

[Walter Roberson]

Simplified version that does it all in one, producing a character string:

   regexprep(filename,{'(?<=^[^_]+_[^_]+_)[^0-9]+','_[^_]+\.csv$'}, '')

[Calabrese]

Walter could you give me an example on how to extract different parts of this filename?

BurnIn_2ndary_volt_curr_columnar_20150528_1500_IAM002.csv

I also have a range3 (which is a character string that is equal to 2324_0226) that I would like to tack onto it. Examples of what I would like to extract from the original are below.

BurnIn_2ndary_volt_curr_20150528_IAM002_

BurnIn_2ndary_20150528_IAM002_

BurnIn_2ndary_20150528_

Now I would like to combine the existing string range3 to produce the following.

BurnIn_2ndary_volt_curr_20150528_range3_IAM002 or
BurnIn_2ndary_volt_curr_20150528_2324_0226_IAM002

BurnIn_2ndary_volt_curr_20150528_IAM002_2324_0226

BurnIn_2ndary_20150528_IAM002_2324_0226

BurnIn_2ndary_20150528_2324_0226