I have a csv file with more number of headers. Each time I am getting this file, I wish to change the name of the headers.
Sample File:
Name Price .....
Cat 5000
Dog 8000
I wish to change the header name "Price" to "Rate". I can't do it manually each time. Is there any automation tool available so that i can feed in the required changes and the file which will inturn return the file after the applied changes.
Thanks
Related
I am running a big set of simulations in Dymola using a script, so far, it works well.
However, it remains incomplete because all the results are still in .mat and I have not find a way to automatically save them as .csv.
I found the DataFiles.convertMATtoCSV() function, but it requires me to specify a list of variables to export. I would like it to export all the variables without writing them one by one, is it possible?
In the Dymola Manual, there is a section "Saving all values into a CSV file".
It contains the following example code:
// Define name of trajectory file (fileName) and CVS file
// (CSVfile)
fileName="PID_Controller.mat";
CSVfile="AllVariables.csv";
// Read the size of the trajectories in the result file and
// store in 'n'
n=readTrajectorySize(fileName);
// Read the names of the trajectories
names = readTrajectoryNames(fileName);
// Read the trajectories 'names' (and store in 'traj')
traj=readTrajectory(fileName,names,n);
// transpose traj
traj_transposed=transpose(traj);
// write the .csv file using the package 'DataFiles'
DataFiles.writeCSVmatrix(CSVfile, names, traj_transposed);
This should do what you want. Also it gives room for customization if necessary later...
I use Stata 12.
I want to add some country code identifiers from file df_all_cities.csv onto my working data.
However, this line of code:
merge 1:1 city country using "df_all_cities.csv", nogen keep(1 3)
Gives me the error:
. run "/var/folders/jg/k6r503pd64bf15kcf394w5mr0000gn/T//SD44694.000000"
file df_all_cities.csv not Stata format
r(610);
This is an attempted solution to my previous problem of the file being a dta file not working on this version of Stata, so I used R to convert it to .csv, but that also doesn't work. I assume it's because the command itself "using" doesn't work with csv files, but how would I write it instead?
Your intuition is right. The command merge cannot read a .csv file directly. (using is technically not a command here, it is a common syntax tag indicating a file path follows.)
You need to read the .csv file with the command insheet. You can use it like this.
* Preserve saves a snapshot of your data which is brought back at "restore"
preserve
* Read the csv file. clear can safely be used as data is preserved
insheet using "df_all_cities.csv", clear
* Create a tempfile where the data can be saved in .dta format
tempfile country_codes
save `country_codes'
* Bring back into working memory the snapshot saved at "preserve"
restore
* Merge your country codes from the tempfile to the data now back in working memory
merge 1:1 city country using `country_codes', nogen keep(1 3)
See how insheet is also using using and this command accepts .csv files.
I'm using v5.1.1 of JMeter and attempting to use the "CSV Data Set Config". The file is read correctly as I can tell from the Debug Sampler/Results Tree, but the file is not being read line by line. In other words, it reads the first line and never proceeds to the next line for processing.
I would like to use the data inside the CSV to iterate over a series of HTTP Requests to an external API. I currently have a single thread with only the "CSV Data Set Config" and "HTTP Request".
Do I need to wrap this with a ForEach controller or another looping construct? Perhaps I'm missing it but I do not see in the documentation that would indicate it's necessary.
Thanks
You dont need to wrap this in a ForEach loop. First line in the CSV file is a var name:
Let's say your csv file looks like
foo, bar
1, John
2, George
3, Laura
And you use an http request sampler
then ${foo} and ${bar} will get iterated sequentially. However please make sure you are mindful about the CSV Data Set Config options. The following options works ok for me:
By default CSV Data Set Config doesn't trigged any "looping", it reads next line from the CSV file for each thread (virtual user) for each iteration.
So if you want to see more values from the CSV file - either add more users or loops or both.
Given
This CSV file:
line1
line2
line3
Following CSV Data Set Config setup:
And the following Thread Group setup:
You will get the following values (assuming __threadNum() function to visualize current virtual user number and ${__jm__Thread Group__idx} pre-defined variable to show current Thread Group iteration) :
Check out JMeter Parameterization - The Complete Guide article for more information on various approaches on parameterizing JMeter tests using external data sources
Is it possible for each thread select the same row from the CSV file?
eg. I have 5 users and only 5 records (rows) in my CSV file. In each iteration, the 1st value from CSV should be assigned to User1, similarly for all users.
User1: myID1,pass1,item1,product1
User2: myID2,pass2,item2,product2
User3: myID3,pass3,item3,product3
User4: myID14,pass4,item4,product4
User5: myID15,pass5,item5,product5
.
.
Any solution, please?
If you have only 5 threads and 5 lines in CSV I would suggest considering switching to User Parameters instead of working with CSV.
If your CSV file can have > 5 lines and your test can have > 5 virtual users and requirement like "user 1 takes line 1" is a must, you will have to pre-load the CSV file into memory with a scripting test element like Beanshell Sampler like:
Add setUp Thread Group to your Test Plan (with 1 thread and 1 iteration)
Add Beanshell Sampler and put the following code into "Script" area:
import org.apache.commons.io.FileUtils;
List lines = FileUtils.readLines(new File("test.csv"));
bsh.shared.lines = lines;
The above code will read the contents of test.csv file (replace it with relative or full path to your CSV file) and store it into bsh.shared namespace
Add Beanshell PreProcessor as a child of the request where you need to use the values from the CSV file and put the following code into "Script" area:
int user = ctx.getThreadNum();
String line = bsh.shared.lines.get(user);
String[] tokens = line.split(",");
vars.put("ID", tokens[0]);
vars.put("pass", tokens[1]);
vars.put("item", tokens[2]);
vars.put("product", tokens[3]);
The above code will fetch the line from the list, stored in the bsh.shared namespace basing on current virtual user number, split it by comma and store the values into the JMeter Variables so you will be able to access them as:
${ID}
${pass}
${item}
${product}
See How to Use BeanShell: JMeter's Favorite Built-in Component guide for more information on using Beanshell scripting in JMeter tests.
Is there an efficient command-line tool for prepending lines to a file inside a ZIP archive?
I have several large ZIP files containing CSV files missing their header, and I need to insert the header line. It's easy enough to write a script to extract them, prepend the header, and then re-compress, but the files are so large, it takes about 15 minutes to extract each one. Is there some tool that can edit the ZIP in-place without extracting?
Fast answer, no.
A zip file contains 1 to N file entries inside and all of them works as un splitable units, meaning that if you want to do something on an entry, you need to process this entry completely (i.e. extracting).
The only fast operation you can do is adding a new file to your archive. It will create a new entry and append it to the file, but this is probably not what you need