Link to URL/File
Use the Link to URL/File option to create a live link to files that are saved locally or online. Key features include:
- Link to CSV or text file formats
- Link to datasets in a JSON format
- Link to subsets of larger datasets
- Option to add a timed reload of data
- Option to save column content for offline use
- Reorder columns without changing the source data
Linked columns of data are organized in groups similar to a Column group.
You can recognize a group of linked columns by the file icon on the left of the group object.
When a link is made to JSON data, the icon will change as shown. For examples using the JSON format, see the webpage on JSON.
Click the left side of the object to expand the group. Each linked column will have a column object. For example, here is a group of five linked columns.
- To Delete: Select the column object and click the delete key.
- To Reorder: Click and drag the objects from the column list or data table.
- To Hide/Show: Click the show check box.
- To Highlight: Click the grey arrow on the right side of the object.
NOTE: When you delete a linked column object you are not changing the source data file. You are only removing the linked column from your DataGraph file.
When the columns are shown in the data table, the entries are shown in bold to indicate that they are not editable entries since they are linked from a file.
Data in linked columns can be used in mathematical expressions in the same way as any data column for entered data. For example, here an Expression column has been added to the linked group, and a linked column name is used in the expression.
IMPORTANT: Although you can add other column types in a linked group such as Expression columns, the linked columns must remain in the linked object group to connect properly to the source data file.
Link to a File
You can create a link to a file by:
- using drag and drop from a browser,
- using the file manager to select a local file, or
- manually entering the file location (online or local).
The examples below use the Palmer Penguins Dataset. Use the following URL to replicate the examples below for the CSV file format.
The fastest way to link to all the data from an online file is to drag and drop a URL from a browser onto the data side panel. Watch the following video for a demonstration. If you prefer to pick a subset of columns, see the section below on Manual Entry.
Link to a local file by creating the link object manually and then use the Finder to select the file. In this video, a gear menu shortcut is used to link all the columns in the data set.
File links can be added manually for either local or online sources of data.
STEP 1: Click the Other drop-down menu and select the Link to URL/File option.
This creates the file link object. Similar to a column group, the object is used to show and manage all the columns that come from the link.
STEP 2: Click to expand the inner section of the object.
STEP 3: Enter the URL or local file location. If the file is read properly, the list of columns in the file will be populated below.
To link an online file, enter the URL.
To link a local file, enter the location directly or click the file icon to select a file from the Finder.
STEP 4: Add linked columns.
To add one column at a time, use the check marks.
To add a group of columns, highlight the columns and select Create selected columns from the gear menu.
To add all columns, select Create missing columns from the gear menu.
Step 5: Check the Data Type
When you link data, DataGraph assesses the entries in each column and assigns the column to either a Number, Text, or Date. The icon indicates the data type.
If the assigned type is not correct, click the gear menu to change the type. This does not change the data, only how the entries are interpreted.
Step 6: When you have all the data columns set up you can collapse the inner section of the group.
By default, the data is not saved in your DataGraph file. The data is reloaded when you first enter the file location, change the location, or open a file. At any time, you can force a reload of the data by clicking the reload symbol shown here.
If the object is collapsed you can reload from the gear menu.
Reload on Change
Click this button to force a reload when the path name is edited. This is checked by default.
Save Column Content
If you check ‘Save column content‘, the data is saved with the file. Thus, a reload will not occur when you open a file and the data will be available when you are offline. This is NOT checked by default.
Check this button if your data is changing on a regular time increment and you want to automatically have the data reloaded/refreshed. You can also specify the time increment in the following units:
When you have a timed reload you will see a progress indicator in the top right corner. When this completes the circle, the data will be reloaded.