Gap Check and Fill
Description
Modern data from the National Climatic Data Center may have gaps within the dataset due to missing data. Dendro Tools requires the removal of any gaps within a dataset because modeling, analyses, and graphing in other tools assume that input data are continuous and any dates with missing data are denoted as missing (i.e., have a value of "-99"). This tool analyzes a dataset for gaps and adds the missing dates into the proper location (e.g., Fig. 1).
Discussion of the Output Data
The file contains all the original data along with all dates that are missing. Data associated with each date missing from the dataset are output as "-99" to denote missing (see Fig. 1 below).
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Figure 1. In this example, the dataset on the left is missing May 1918. Running this tool adds May 1918 into the proper location (dataset on the right), but the precipitation data are denoted as missing (i.e., “-99”). This tool also adds days to the start of the dataset when the first date with data is not the first day of the month. For example, if the dataset starts on 12 June 1950, then this tool will add 1 June 1950 through 11 June 1950 into the dataset in the proper location. |
Input
Input File
Select the input file by clicking on "Browse" and navigating to the proper file.
Input Data Format
Year / Month / Day / Data
Each "/" is a tab (i.e., data should be tab-delimited).
Start Row
This input is the row number where the main data to be processed begin in the dataset. An example of how row numbers are entered is shown in Figure 2 located in the Running Dendro Tools topic.
Data Columns
The number of columns in the main data, which should be checked for gaps. An example of how column numbers are entered is shown in Figure 2 located in the Running Dendro Tools topic. Do note that this field is asking for the total number of data columns not the data columns themselves and the count of these columns does not include dates (e.g., there would be two data columns in the example located in the Running Dendro Tools topic).