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Tagged: csv update
This topic contains 10 replies, has 2 voices, and was last updated by jwk 1 year, 1 month ago.
I am trying to get my canvasjs column chart to update from a local csv file. (foobar.csv)
I got the column graph to work. See https://chem2.uaf.edu/facilities/Test/csvtest.htm
but a version containing an updateChart() section fails. See https://chem2.uaf.edu/facilities/Test/csvtest-update.htm
I tried to copy the json updateChart() format, but this is not working.
So: How do I code the updateChart() section properly retrieve data from a csv file that might contain changing data?
Can you please check browser console for error Uncaught SyntaxError: Unexpected token ) - csvtest-update.htm:72. It seems like there is some mismatch of brackets in your code.
Uncaught SyntaxError: Unexpected token ) - csvtest-update.htm:72
If you are facing any other issue, kindly create jsfiddle or share static html/php files over onedrive/google-drive so that we can understand your code better and help you out?
I attempted to correct the browser error by removing the “)”, but that just gave a different browser error…
The foobar.csv :
Sorry, the hyperlinks for the 2nd and 3rd should be switched.
You have missed out closing window.onload function because of which its throwing error that can be seen in browser-console. Also we would suggest you to instantiate chart once and update dataPoints on every ajax-request instead of creating new chart on every ajax-request. Please download the updated code and let us know your feedback.
Thank you for the suggested changes to the CVS updating chart! It is now updating. However, the number of columns increases by 4 (which is the number of rows in the CVS file) after each timeout interval..
Perhaps the new dataPoints should overwrite the old dataPoints?
I created a jsfiddle page for this code:
Another problem with the suggested code ( https://jsfiddle.net/jwkeller/yy3hdLtz/ ) is that, even at time=0, TWO copies of the CSV file data are plotted.
OK I fixed it. See the above jsfiddle page. All I did was modify the updateChart function with some lines that removed the previous dataPoints using a dataPoints.shift statement.
Once I have this webpage fully functional, I will update this forum with the URL so you can see it in action in the “real world”.
Glad that you fixed the issue :)
OK it seems to be working. https://chem2.uaf.edu/facilities/WebMO/
Much of the time these servers are not being used. However, anyone can send in a job by logging on as Guest, pwd webmo
Do New Job, Create New Job, Lookup-Import-By Name, tetracyclin, OK.
Click the right arrow (bottom right), choose NWChem (a quantum chemistry package), right-arrow,choose geometry optimization and all the other as defaults, click the advanced tab, change 2 to 8 under Cores, submit the job by clicking the right arrow.
The bar graph should register under Rosewill.
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