# System.dataset.addRow error coercing string to number

**URL:** <https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638>\
**Category:** Ignition\
**Tags:** perspective, scripting\
**Created:** [August 31, 2023, 6:34pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638 "2023-08-31T18:34:44Z")\
**Posts on this page:** 16\
**Page:** 1

<div class="post-metadata">

**Author:** ![Logan\_Krohn](https://avatars.discourse-cdn.com/v4/letter/l/ad7895/32.png) [@Logan\_Krohn](https://forum.inductiveautomation.com/u/Logan_Krohn)\
**Post date:** [August 31, 2023, 6:34pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638/1 "2023-08-31T18:34:44Z")

</div>

I am trying to add a header row to a dataset using system.dataset.addRow. The dataset comes from a table component displaying strings and floats depending on the column. The newRow I am trying to add is a list of tag names and are strings. I don't know how to fix the error I am getting involving being unable to coerce a tag name to a number. Thank you

 ![Capture](https://us1.discourse-cdn.com/inductiveautomation/original/3X/4/3/43e5abecc97ca6b4ac55e0b05dae48f389b24b50.png)

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<div class="post-metadata">

**Author:** ![Logan\_Krohn](https://avatars.discourse-cdn.com/v4/letter/l/ad7895/32.png) [@Logan\_Krohn](https://forum.inductiveautomation.com/u/Logan_Krohn)\
**Post date:** [August 31, 2023, 6:36pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638/2 "2023-08-31T18:36:30Z")

</div>

```auto
	import csv
	
	self.props.style['borderStyle'] = 'inset'
	self.props.style['borderWidth'] = '2px'
	data = self.parent.parent.getChild("Table").props.data
	cols = data.getColumnNames()
	idx = []
	for c in cols:
		if c != 'None':
			idx.append(cols.index(c))
#	data = system.dataset.filterColumns(data,idx)
	tags = list(self.view.custom.complianceConfig.tagPaths)
	tagNames = list(self.view.custom.complianceConfig.tagNames)
	for i in range(len(tagNames)):
		if tagNames[i] == None or tagNames[i] == '':
			continue
		else:
			tags[i] = tags[i] + '.Name'
	pops = []
	for t in tags:
		if '.Name' not in t:
			pops.append(tags.index(t))
	for x in reversed(pops):
		tags.pop(x)
	realNames = system.tag.readBlocking(tags)
	newRow = []
	for name in realNames:
		newRow.append(name.value)
	newRow.insert(0,'')
	data = system.dataset.filterColumns(data,idx)
	
	data = system.dataset.addRow(data, 0, newRow)
	export = system.dataset.toCSV(data)
	system.file.writeFile('tempfiles/exportTemp.csv',export)
	with open('tempfiles/exportTemp.csv','ab') as f:
		writer = csv.DictWriter(f,fieldnames=newRow)
		writer.writeheader()
		f.close()
#	csvData.insert(1,newRow)

	
	date = str(system.date.format(system.date.now(), "yyyy-MM-dd"))
	filename = self.parent.parent.parent.parent.getChild("FlexContainer").getChild("Dropdown").props.value + " Compliance " + date
	system.perspective.download(filename + ".csv", system.file.readFileAsBytes('tempfiles/exportTemp.csv'))

```

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<div class="post-metadata">

**Author:** ![pascal.fragnoud](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pascal.fragnoud/32/24728_2.png) [@pascal.fragnoud](https://forum.inductiveautomation.com/u/pascal.fragnoud)\
**Post date:** [August 31, 2023, 6:37pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638/3 "2023-08-31T18:37:33Z")

</div>

What do you mean, add a header row with `addRow` ? Datasets have headers already, and that's not how you configure them

I'll look through the code.

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<div class="post-metadata">

**Author:** ![Logan\_Krohn](https://avatars.discourse-cdn.com/v4/letter/l/ad7895/32.png) [@Logan\_Krohn](https://forum.inductiveautomation.com/u/Logan_Krohn)\
**Post date:** [August 31, 2023, 6:38pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638/4 "2023-08-31T18:38:44Z")

</div>

Also in my code there is a csv.writer for the header but it appends the tag names to the end of the csv file instead of the beginning. I was attempting to add the header using system.dataset.addRow before converting to csv but if changing my writeheader() is easier I would appreciate some input.

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<div class="post-metadata">

**Author:** ![bkarabinchak.psi](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/bkarabinchak.psi/32/83567_2.png) [@bkarabinchak.psi](https://forum.inductiveautomation.com/u/bkarabinchak.psi)\
**Post date:** [August 31, 2023, 6:39pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638/5 "2023-08-31T18:39:59Z")

</div>

`import csv` uses the jython csv writer and in that case it does not know about Ignition datasets. I would suggest using one of the built-in solutions for exporting Ignition datasets to csv like `system.dataset.exportCSV` [system.dataset.exportCSV - Ignition User Manual 8.1 - Ignition Documentation](https://docs.inductiveautomation.com/display/DOC81/system.dataset.exportCSV)

This one has the option to write the headers built in and knows about the Ignition datasets so it will just grab your column names for you. No extra row at the top required.

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<div class="post-metadata">

**Author:** ![Logan\_Krohn](https://avatars.discourse-cdn.com/v4/letter/l/ad7895/32.png) [@Logan\_Krohn](https://forum.inductiveautomation.com/u/Logan_Krohn)\
**Post date:** [August 31, 2023, 6:40pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638/6 "2023-08-31T18:40:52Z")

</div>

I see what you are saying now. Thank you I will look at the writeheader I have in the code that is adding the header to the very end of the dataset.

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<div class="post-metadata">

**Author:** ![pascal.fragnoud](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pascal.fragnoud/32/24728_2.png) [@pascal.fragnoud](https://forum.inductiveautomation.com/u/pascal.fragnoud)\
**Post date:** [August 31, 2023, 6:43pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638/7 "2023-08-31T18:43:10Z")

</div>

Ok I'm sorry but this code makes very little sense at first glance and I don't have time to study it.  
If you can tell me what your input is and what the output should be, I'll give refactoring it a shot.

edit: If I may, the whole point of using a context manager on `open` is that you don't need to manually call close.

```python
with open('tempfiles/exportTemp.csv','ab') as f:
	writer = csv.DictWriter(f,fieldnames=newRow)
	writer.writeheader()
	f.close()

```

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<div class="post-metadata">

**Author:** ![bkarabinchak.psi](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/bkarabinchak.psi/32/83567_2.png) [@bkarabinchak.psi](https://forum.inductiveautomation.com/u/bkarabinchak.psi)\
**Post date:** [August 31, 2023, 6:44pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638/8 "2023-08-31T18:44:49Z")

</div>

I think ultimately he just wants to make a CSV file by the looks of it. He's converting a dataset into a CSV string and then using the jython library `csv` to write it.

He may never be able to do it this way though. He's trying to add a row of "headers" so that the `csv` library will write that first, except that he has a column with non-string types, so thats what the error is being caused from.

I would suggest just using system.dataset.exportCSV - no additional row writing required.

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<div class="post-metadata">

**Author:** ![Logan\_Krohn](https://avatars.discourse-cdn.com/v4/letter/l/ad7895/32.png) [@Logan\_Krohn](https://forum.inductiveautomation.com/u/Logan_Krohn)\
**Post date:** [August 31, 2023, 6:46pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638/9 "2023-08-31T18:46:07Z")

</div>

I am going to do that. I understand the error I am getting now. I will let you guys now how that works out. Thank you

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<div class="post-metadata">

**Author:** ![Logan\_Krohn](https://avatars.discourse-cdn.com/v4/letter/l/ad7895/32.png) [@Logan\_Krohn](https://forum.inductiveautomation.com/u/Logan_Krohn)\
**Post date:** [August 31, 2023, 6:48pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638/10 "2023-08-31T18:48:21Z")

</div>

Sorry about the code I inherited it from someone else and I am still very green to scripting in this environment. I will remove the close() and you don't need to refactor anything.

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<div class="post-metadata">

**Author:** ![bkarabinchak.psi](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/bkarabinchak.psi/32/83567_2.png) [@bkarabinchak.psi](https://forum.inductiveautomation.com/u/bkarabinchak.psi)\
**Post date:** [August 31, 2023, 6:50pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638/11 "2023-08-31T18:50:02Z")

</div>

> [@Logan\_Krohn](#):
>
> ```auto
> data = system.dataset.addRow(data, 0, newRow)
> export = system.dataset.toCSV(data)
> system.file.writeFile('tempfiles/exportTemp.csv',export)
> with open('tempfiles/exportTemp.csv','ab') as f:
> writer = csv.DictWriter(f,fieldnames=newRow)
> writer.writeheader()
> f.close()
> 
> ```

I would suggest all of this be replaced with  
`system.dataset.exportCSV('tempfiles/exportTemp.csv',1,data)` - this will write your dataset with the column name headers to your file path.

As a general rule, you should check if there is a first party way (ie through Ignitions `system.*` functions) to do something as those functions know how to deal with Ignition objects.

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<div class="post-metadata">

**Author:** ![pascal.fragnoud](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pascal.fragnoud/32/24728_2.png) [@pascal.fragnoud](https://forum.inductiveautomation.com/u/pascal.fragnoud)\
**Post date:** [August 31, 2023, 6:56pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638/12 "2023-08-31T18:56:10Z")

</div>

Can't help it, I have to do it.  
But not right now because it 9pm over here and I have to eat.

I'll come back with a few hints and tips that should help you clean this up.

---

<div class="post-metadata">

**Author:** ![lrose](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/lrose/32/62724_2.png) [@lrose](https://forum.inductiveautomation.com/u/lrose)\
**Post date:** [August 31, 2023, 9:05pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638/13 "2023-08-31T21:05:57Z")

</div>

> [@bkarabinchak.psi](#):
>
> This one has the option to write the headers built in and knows about the Ignition datasets so it will just grab your column names for you. No extra row at the top required.

I mean, so does `system.dataset.toCSV()` and it does it by default.

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/5/b/5ba59538dd7647610a8c6d659340b810960de70b.png)

The big problem with `exportCSV()` is that it is only available in Vison Client scope.

Here is a more concise and clear way to write your script, that I believe will produce exactly the same output.

```python
self.props.style['borderStyle'] = 'inset'
self.props.style['borderWidth'] = '2px'
data = self.parent.parent.getChild("Table").props.data
idx = [i for i,c in enumerate(data.getColumnNames()) if c != 'None']
tagNames = [tag + '.Name' for tag,Path in zip(list(self.view.custom.complianceConfig.tagPaths),list(self.view.custom.complianceConfig.tagNames)) if !path]

realNames = system.tag.readBlocking(tags)
newRow = [''] + [name.value for name in system.tag.readBlocking(tags)]
data = system.dataset.filterColumns(data,idx)
data = system.dataset.addRow(data, 0, newRow)
export = system.dataset.toCSV(data)

date = system.date.format(system.date.now(), "yyyy-MM-dd")
filename ="{} Compliance {}.csv".format(self.parent.parent.parent.parent.getChild("FlexContainer").getChild("Dropdown").props.value,date)
system.perspective.download(filename, export)

```

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<div class="post-metadata">

**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\
**Post date:** [August 31, 2023, 9:11pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638/14 "2023-08-31T21:11:09Z")

</div>

You don't need to write the file out to disk and read it back in as bytes; `system.perspective.download` can directly handle input strings and will download them as UTF-8 text.

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<div class="post-metadata">

**Author:** ![lrose](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/lrose/32/62724_2.png) [@lrose](https://forum.inductiveautomation.com/u/lrose)\
**Post date:** [August 31, 2023, 9:11pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638/15 "2023-08-31T21:11:44Z")

</div>

Oh, yeah, I meant to fix that too, I'll edit.

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<div class="post-metadata">

**Author:** ![Logan\_Krohn](https://avatars.discourse-cdn.com/v4/letter/l/ad7895/32.png) [@Logan\_Krohn](https://forum.inductiveautomation.com/u/Logan_Krohn)\
**Post date:** [August 31, 2023, 9:14pm UTC](https://forum.inductiveautomation.com/t/system-dataset-addrow-error-coercing-string-to-number/78638/16 "2023-08-31T21:14:59Z")

</div>

You guys are awesome! Thank you so much