How to Import Text Files into Global Mapper

Bringing data into Global Mapper is a straightforward process, but when it comes to text files, customization is sometimes required. Text files do not have a standard file structure; that is to say, there isn’t a predictable formula that Global Mapper can use to locate important information in the file; for example, to separate X/Y fields from other information. When the file is imported into Global Mapper, the text file import wizard will automatically open to allow you to specify where the important data is and how it should be read. This blog will cover the basics, tips, and tricks for bringing in text data with the wizard. For specifics on scripting style settings and other special attributes, please consult the Knowledge Base. 

Global Mapper can import all sorts of text files. If you have a file that isn’t interacting with the importer, for example, you can’t see data in the preview window, try exporting it as a .CSV file before bringing it into Global Mapper. Sometimes files are formatted for specific software, such as Excel, and need to be reformatted. If this is the case, please send the file to technical support. 

Coordinate structure

Global Mapper supports the most common Coordinate Formats. The default option is typically the best choice, especially if you’re importing from software that is accustomed to working with spatial data, such as a GPS unit. There are a few different decimal options, and it can be difficult to discern which is which. An easy way to do this is by matching the format with the dropdown choices .

Projection

Unlike many other spatial data files, text files don’t inherently contain projection information. Like shapefiles, if there is a prj file in the same folder on your computer that has the same name as the text file, Global Mapper will assign that projection automatically. 

If the file does not have an accompanying prj file, Global Mapper will prompt you to set the projection manually. As there are many projection and datum options and combinations, we recommend reaching out to the data provider if you are unsure of the projection. 

Troubleshooting

Here are a few commonly reported questions, and some suggestions, for remedying the situation. 

If your area feature is a mess of unconnected lines, be sure the import type is set to the area, and the Area Line/Area features box is checked. Sometimes features will be separated with a character at the end of the final line or with an empty line between features, and sometimes they can restate the initial coordinate. Either way, check the box to tell Global Mapper to look for these signals. 

In terms of positioning, there are a few things that can be targeted. If the layer is in the wrong location, you may have the wrong projection. Alternatively, if it’s in the correct location but oriented incorrectly, you may need to switch the Coordinate Order setting in the top left of the import wizard. Finally, if it’s in the correct location but at the wrong scale, you may have the wrong datum. 

If all else fails, please send your text file to the Technical Support team geohelp@bluemarblegeo.com with a screenshot of your import and projection settings.