The Import command (from the File menu) is used to import ASCII data (either in card-image format or gcl format) into GCLAS.
GCLAS can read streamflow time-series data in the USGS National Water Information System (NWIS) daily-values and unit-values card-image formats.
GCLAS can read water-quality data in rdb-style tab-delimited ASCII format and in the SEDCALC "SEDATA" (B-card) format. GCLAS also can create and read data files in its own format, referred to as "gcl." The gcl format is equivalent to the tab-delimited rdb format.
Currently, there is no way to hand-enter measured concentration data directly into GCLAS, so all measured data sets must either be created/output from a USGS database or assembled in some other application (such as SEDCALC or a spreadsheet) and then imported. A Microsoft® Excel 2000* template (called input_template.xls) for constructing a concentration data file is available and is included as part of the GCLAS installation (in the folder or directory called "data"). To use the spreadsheet, do the following:
Once you have entered your data, left click on "File" in the Excel menu bar and then left click on the "Save as" option. A file window will open with a pick list titled "Save as type" at the bottom. Choose "Text (tab delimited)" or "CSV (comma delimited)" depending on which you entered in the header portion of the Excel file. Enter a name to save the file in (use the same file name that you specified in the header of the Excel file), and then left click on the "Save" button. Unless you placed the file name in quotes (i.e. "filename.gcl"), Excel will append an extension of ".txt" or ".csv" to the file, depending on the format in which the file was saved. The extension of the newly saved file (not the Excel file) should be renamed to ".gcl" if the file was saved with another extension. (NOTE: Some versions of Excel (including Excel 2000) sometimes erroneously omit end-of-row delimters on rows where there is no value in the last column. The omission does not occur in all cases, but GCLAS will not read the data properly when the delimiters are omitted. To avoid this problem, make sure that the last column of data is one that contains an entry for every row.)
The Open command (from the File menu) is used to open a previously created GCLAS project file. A GCLAS project file, which has an extension of ".gpf", is a special file format the GCLAS creates (using the Save As option on the GCLAS File menu) that can contain all input data, coefficient information, and computed loads associated with a GCLAS session.
Once you have opened a GCLAS project file, you must select the data node corresponding to the concentration parameter from the file tree panel (located in the upper left corner of the GCLAS display). Select the node by left clicking on the toggles in the file tree panel until the concentration node is visible, and then left click on the concentration node (causing the node to be highlighted as shown in the example below).
After the concentration node has been selected, click the right mouse button (with the cursor over the node) and choose the option to Edit a GCLAS year (example shown below) by clicking the left mouse button on the option.
A new window window will appear (example shown below) positioned to a tab labeled "Edit/create". Click the left mouse button on the row corresponding to the water year that you wish to edit or view, then left click on the "Edit GCLAS year" button. Once that is done, the graph and tabular views of the selected data will be displayed and the project data can be edited or viewed.
*"Microsoft" is a registered trademark of Microsoft Corporation in the United States and
other countries.